Venom-SC for VM-1 Release Notes

If you are looking for a simple overview of how the language has changed since the Tutorial Guide was printed then you might want to see the Tutorial Update.

Contents

• Installing a new version of Venom-SC
• Document structure - notes
• Release history (current first)

Installing a New Version

1. Remove the flash chip from its socket
2. Then, either
   1. Reprogram it with the new version, OR,
   2. Exchange it for a chip containing the new version
3. Replace the chip holding the new version in the socket

Removing the flash

Replacing the flash

Burning new code into a flash

Document Structure

Major  Changes	Lists changes to the language syntax or operation that mean you may have to alter your source code. We will only make changes of this kind where there is an overwhelming advantage to doing so. Check all the Major Changes between the version you have been using and the current version. If any of them apply to you, please make sure your application code is changed to suit.
New Features	Lists features added to the language or objects.
Bugs Fixed	Lists bugs fixed where the bug may have significantly affected use of the system.

The following two small sections don't fit into the structure of formal releases, and so are documented here.

Current Limitations

• The ProtAnalyser object only scans floating-point numbers to 6 figures of precision.
• There may be problems if you enter a new definition of a procedure while a task is running it. Stop all tasks before downloading code to avoid this.
• FAT FileSystem doesn't support FAT32. You should be able to format cards up to 2Gb in "FAT" (FAT16) with Windows. Most portable devices (cameras etc.) that use MMC/SD cards can't support FAT32 either.
• Second I²C Bus: RealTimeClock can't use it yet.
• HTTP doesn't support POST method yet.

To do list

• Compare message works on strings but not on text buffers.

Current Bugs

Release History

2008 07 30

Major Changes

New Features

• DECLARE: This new keyword allows you to pre-define all the global names you will use in a project to catch spelling mistakes and other errors more quickly. see the Help file for more information.
• String Flush: The String object now takes the Flush message - which removes all text from before the Readpoint.
• Debug(10): This is a beta release of a 'Global Code Check'. It checks through every procedure in your code and lists out the usage of each global variable name, allowing you to see if your code never writes to it, or never reads it, for example. This is useful for both removing redundant code and detecting latent bugs. It is best used immediately after clearing the memory in the VM-1 and downloading all the code.

Bugs Fixed

• Heap bug: when the block after a block larger than 64K Bytes was freed then the heap was corrupted.
• MMC card initialisation: This is now being done correctly, before CS is asserted.
• Array checksum: Calling Valid would correct the checksum, so Valid only showed a problem the first time it was called.
• Array.Copy: Copy with no parameters copied the array but returned the original.

2008 04 08

Major Changes

New Features

Bugs Fixed

• FTP Client: could become erratic if more than one task was using networking protocols (TCP/IP). Responses on the control link can arrive in unexpected order; the FTP client now handles this correctly.
• TCP: Under some conditions a TCP active open would report failure when the connection had in fact opened succesfully. This also showed up when using FTP with multiple tasks using networking protocols.
• ProtAnalyser: Get message with a string object as 1st parameter and no second parameter would erroneously allow space character as a default delimiter.

2008 03 27

Major Changes

• RAM File System: The RAM disk no longer uses a proprietary filesystem: it now uses the same FAT file system as is used for MMC/SD memory cards. Advantages over the previous RAM filesystem:
  • Longer filenames are allowed.
  • Subdirectories are allowed.
  • Reduction in code size for the Venom system.
  • More uniform programmer interface - both filesystems behave in substantially the same way
  • smaller memory overheads
  Possible compatibility issues:
  • File names are no longer case sensitive
  • Code that relied on directory listings in a particular format may have to be rewritten.
  • The set of characters allowed in filenames is different, and '/' is a directory separator in a pathname.
  As with the previous RAMDISK, a thorough check on the integrity of the file system is performed when the file system is created. Any file with corrupt directory or allocation information is simply removed. Programs should be designed to recover gracefully from non-existence of any file.

New Features

Bugs Fixed

• HTTP Server: A bug which could cause erratic behaviour has been found and fixed.
• Safedata Checksum did not compute correctly for EEPROMS with more than 256 memory locations.

2008 01 16

Major Changes

New Features

Bugs Fixed

• RAM Filing System occasionally displayed two lines of hex numbers (debug code) via serial 1.
• TCP: Improved scheme for allocation of port numbers to prevent recent numbers from being re-used after the VM-1 is reset. This caused occasional refused connections when many connections to the same server were opened and closed before and after restarting the VM-1.
• When initializing integer arrays of 8 or 16 bit element sizes, a compiler warning is now generated if an initialiser value is too large for the array element size.

2007 10 18

Major Changes

• Heap: The heap memory allocation system has been extensively re-written using an different topology to deal with the exessive time taken to free up blocks in a system where a large number of blocks have been allocated. This problem had been unseen until the introduction of the String object and Buffer of Any, which made creating large numbers of independent objects desirable for the first time.
  One of the side effects of adopting the new topology (a doubly-linked list) is that heap blocks now take an extra two bytes each. There is probably no need to change your source code unless you are using large numbers of objects that nearly fill the RAM.
• GraphicsLCD - QVGA: In order to apply the correct power supply sequencing for the Hitachi SP14Q006 and similar displays, control over the LCDPWRON/OFF signals coming off the QVGA Driver module (5809) has been extracted out of the MAKE command and put in the On message. It is now necessary use the following code in order to correctly power up the SP14Q006 LCD. If you don't include the On message then the display will not be turned on.

  MAKE p GraphicsLCD (3 320 240)
WAIT 50 ; Wait at least 50mS.
p.On

  Note for the Hitachi SP14Q006 and similar: if the LCD bias voltage is under software control this ideally should be turned on just before the MAKE, and the MAKE itself should occur within 30mS of powering up. This requirement implies that it is not good practise to power up an LCD panel without initialsing it, though it may be hard to achieve this on every occasion during development.

New Features

• GraphicsLCD - QVGA: On and Off messages to control the LCDPWRON/OFF signals - see Major Changes above.
• Ethernet Protocol: can now use DHCP to assign IP address, default gateway address and DNS server address. DHCP is selected in the MAKE statement by setting the "IP address" parameter to 0.

Bugs Fixed

• Integer constant: The integer constant value $80000000, expressed in hexadecimal, decimal or binary, resulted in code for the value 0 instead.
• RAM File System: crashed during MAKE for an existing file system when the number of files was a multiple of 18.

2007 09 10

Major Changes

• Non-volatile Arrays: Syntax for creation and block initialisation has been changed so it is more intuitive. To create a non-volatile array you should now use MAKE with a third parameter set to NIL:
MAKE nva Array(8,100,NIL)
  To copy the data only from any array to any other array, use Copy:
destination_array.Copy(source_array)
  The old Copy(1) and Reset messages to create and initialise non-volatile arrays will still work for this release but we recommend you change your source to suit the new syntax.
• ProtAnalyser: A change in behaviour with delimiters, introduced with the last release, has been reversed, and some small further refinements added.
  • Initial delimiter characters are not now skipped when reading numbers and strings (but blanks are still skipped with numbers). This means that an empty string can be returned.
  • The "CSV mode" behaviour can be specified for any delimiter character, not just comma.
  • In CSV mode, a newline terminator is retrievable by the GetLast message. (other control characters are ignored; mid-line, GetLast returns a comma or whichever other separator character was specified).
  • The terminator at the end of a string or number is consumed from the input stream, but can be retrieved by a GetLast message. The Look message always returns a preview of the next character from the input stream.
  • When reading numbers, an empty string (i.e. a terminator character encountered before any numeric) returns a value of 0 or 0.0, and Valid is set false, as in the old ProtAnalyser.

New Features

• Analogue drivers: Direct support for the AD7998, MAX1236 and MAX1238 is now in place. Also indirect support for the MCP3421 and ADS1110.
• Tab stops: Tab is now echoed by the VM-1's command line as two spaces to fit with the default value in VenomIDE.
• Command line cache: Typing the Up Arrow key (in VenomIDE and most terminal emulators), or Ctrl-R, will retrieve the last line you typed in at the --> Venom prompt. This feature has existed for some time but was not documented.
• Ethernet Protocol: Creating this with a device select code of 0 suppresses any writing to the device select lines (on the Expansion Bus: channels 30-37), allowing a special hardware configuration where Ethernet and the Expansion Bus can be used together, e.g. for LCDs.

Bugs Fixed

• ProtAnalyser: Reported bug in delimiter string where character after initial '-' was ignored.
• IP Protocol: Time message was not returning correct values after first time of use.

2007 07 03

Major Changes

• ProtAnalyser: The Protocol Analyser object has been redesigned. The new version should be easier to use, and has some extra facilities. In particular:
  • You can choose how end-of-input condition is handled and no longer need to pad the end of a buffer with a dummy terminator
  • Reads numbers in any base up to 36
  • Can read strings direct to a string object
  • Can parse most types of CSV (comma separated value) data
  • More sophisticated method for specifying delimiters
  • Function for simply skipping delimiters or characters in a set
  • Simpler syntax for some operations
  • Find message searches for specific string

New Features

• File f.Get(s) where s is a string object will read a line of text (terminated by CRLF or EOF) from a text file and append it to the string.
• String Object: the Value message interprets the contents as an integer or floating point number, as with the Buffer Value message.
• String Object: now has an internal Readpoint variable and supports the messages Get, Queue, Readpoint and Reset in the same way as a text buffer. This is expected to be useful because it enables a string object to be used as a data source for the Protocol Analyser.
• System.Count message reads or sets a 16 bit unsigned number that is retained during power down and incremented each time the system restarts.
• Macros: The error when a macro name is seen by the compiler before the macro has been defined has now been reduced to a warning. There is no longer a need to clear the controller memory when this occurs.
• HTTP: server object chooses persistent connection or immediate close based on HTTP version and "connection:close" header. This may improve performance in some connections.

Bugs Fixed

• Writing to an array in NVRAM no longer causes a write protect error
• RAM file system file time and date bugs fixed. Also RAM file system can use internet time as a time source, in the same way as the FAT file system.
• Buffer b.Find(pattern, startpos) generates a proper run time error if startpos is out of range, instead of crashing the VM-1
• http Fixed memory leak and problem that caused data corruption in multitasking environment.

2007 03 21

Major Changes

• FAT Filesystem: PRINT formats that list full file paths do not now show a '/' character at the beginning of the path/file name.
• TCP/IP Protocols allocate memory differently, using more when created but with less extra memory use while in operation. The result should be less heap fragmentation and faster TCP/IP performance, but if your application is tight on memory you might want to check the free memory while running.

New Features

• FAT Filesystem: fs.Debug(4,3) and fs.Debug(4, 4) return the number of cache hits and misses, respectively, since the file system was created or last reset. You could use this information to help tune the cache size for an application.
• AsynchronousSerial: serial.Put(a) and serial.Get(a) will transfer data between an array of 8 bit integers and the serial port. Two optional parameters can specify an array start element and number of bytes to transfer.

Bugs Fixed

• FAT Filesystem: PRINT filenames or wildcards in the 1st colon operator were being ignored.
• FAT Filesystem would occasionally output spurious debug information to serial port 1.

2007 03 06

Major Changes

• The amount of memory used by the FAT file system for block cacheing will generally be different. In most cases more memory will be used, but this can be controlled (see below). The cache memory is allocated when the file system is created, and unlike previous versions it does not change during use.

New Features

• Maths: X ^ Y. The 'X raised to the power Y' operation has been implemented.
  Operand types: FLOAT and INT. If both operands are INTs, and Y is positive or zero, then the result is INT. Otherwise the result is FLOAT.
  Operator: the carat character: ^.
  Precedence: it has the same precedence as *, /, DIV and MOD: use ( ) to be clear.
  Optimisation: the ^ operation is constant folded.
• SMTP Protocol supports a simple authentication scheme (AUTH PLAIN) when connecting to a server.
• TCP Protocol: tcp.Get(s) where s is a string object will collect a line of input terminated by CRLF or string capacity.
• AsynchronousSerial: serial.Get(s[, n]) where s is a string object and n is an optional control parameter, stores a line of input in the string terminated by CR or LF or string capacity, and optionally echoed back to the serial line.
• http Protocol: http.Get(s) stores the returned path value in string object s.
• String object: Put message can append a single character (integer parameter as opposed to string)
• CRCGenerator: two simple checksum types added (8 and 16 bit). Also crc.Put(a[, start, length]) efficiently builds up CRC from strings or arrays of parts thereof, and crc.Get(a) works where a is an array of 8 bit elements.
• FAT Filesystem: An optional extra parameter when creating allows you to define how much memory is used for the block cache. fs.Debug(4, n) returns number of blocks (n=1) or bytes of memory(n=2) used by cache.
  fs.Debug(12,n) reports on various MMC block transfer and error statistics.

Bugs Fixed

• Owner Message: This was broken and now fixed.
• RAM FileSystem data corruption and run time errors when more than 18 files were created - fixed.
• SMTP Protocol: The "message-id" header now complies with the syntax described in RCF2822.
• FAT Filesystem and MMC driver: The MMC retries block reads and writes on failure, making it much more robust. The FAT fileystem has a new block cacheing scheme which is faster and allows user control of the memory used, and some associated bugs have been fixed, which caused corruption under obscure and hard-to-reproduce conditions.

2007 01 23

New Features

• Flags parameter to PROGRAM command now active: used by new release of VenomIDE for Download settings.
• Attempt to lock object held by dead task: There is an option to turn off this runtime error. Use this line to turn it off:
  Debug(3) := 8
  We only recommend this for situations where there is no time to remove the source of the underlying error. When the failure occurs, the operating system silently unlocks the object and normal operation resumes. However the locking task may wait for around 255 * Number of Tasks mS before the situation is resolved.

2007 01 08

Major Changes

• TASKs and Locks: There has been a major overhaul of an internal system that deals with the interaction between tasks and locks. Before, when a task ended, for whatever reason, every object in the system was scanned, and if it had been locked by the dead task, it was unlocked so that the object was then free to be used by any other task.
  The new system is much more efficient: if a task has to wait to secure a lock for more than 255 task scheduler cycles (around 255 * Number of Tasks mS) then the waiting task checks to see if the task that holds the lock is alive. If not then a Runtime Error is issued ("Attempt to lock object held by dead task"). We issue a Runtime Error here because well-written programs should not result in tasks ending when they still hold locks on objects used by other tasks. See Release above for workaround if this breaks your application.
  In particular the use of the STOP command is not recommended for use in a live application, only as a development tool. Please see the Tutorial Guide for a thorough discussion of tasks and locking.
• Graphic LCDs: Two graphics LCD drivers based on the SED1560 and SED1520 have been removed. Please contact us if this affects you.

New Features

• FTPClient Protocol Remove message requests removal of a file from the remote server.
• FTPServer Protocol accepts DELE (delete file) command from remote client. Note that a request to delete a directory will do so, removing the entire contents of the directory.
• LIST TASK : When tasks are listed, whether by typing Ctrl-T , or by using the LIST TASK command, the task list now indicated if a task is 'blocked' by another task - i.e. waiting to lock a lock held by another task. This helps you to understand the interaction of tasks and locks in your application, and will show up 'deadlock' if it occurs.
• New Graphics LCD Driver There is a new Graphics LCD driver for displays based on the SED1565, which has a display resolution of 128 x 64. See the Help file and contact us for details.
• SMS protocol object can now accept a Die message.
• FileSystem (RAM) better integrity checks on startup.

Bugs Fixed

• Unwanted debug output removed.
• FTPClient Open now returns correct true/false value.
• Buffer Remove message can now remove sections containing the last element.
• Memory leak in SMS fixed
• Filesystem (RAM) made resistant to corruption that could occur if power cut off during file size update.

2006 11 30

Major Changes

• New Keywords: The words LIBRARY, DECLARE, String and Compare are now system keywords and may no longer be used for your own identifiers. The functions behind these keywords are not all implemented as yet.

New Features

• String object: There is now a String object so you can have variable strings in Venom-SC. Up until now you had to use a Text Buffer to hold variable text data, and string constants to hold static text data. Now you can create strings on the fly. They can do many of the things that a Text Buffer can do, but have a fixed maximum size. They are a bit faster, and more memory-efficient than Text Buffers, especially for short strings. The String object can take the new Compare message. See the latest edition of the Help File for full details.
• Buffer of Anything: There is now a 'Buffer of Anything' type of buffer. This can hold any kind of Venom value, e.g. a single buffer can hold other buffers, arrays, objects of various kinds, strings, integers, floats... anything. This object is a powerful tool for creating lists, etc. See the latest edition of the Help File for full details.
Find for integer buffers: The Find message will now work for integer buffers: it will find the first occurrence of a given integer in a buffer, starting from a given point.
• Buffer: The Put message can append an array or string to a buffer of matching element type. This can also be applied to a subset of the array or string. This is faster than PRINT TO for strings, and much faster than copying one array element at a time.
• CRCGenerator: Creating with a prototype value of 'M' or 'm' makes a MODBUS CRC generator. This behaves in the same way as the standard 16-bit CRC but uses a different algorithm that generates different 16-bit values. It is useful for customers implementing the MODBUS message protocol.
• FTP: The FTPSERVER Protocol now supports file delete and rename commands, and the FTPCLIENT Protocol takes a Name message to rename a remote file.
• UDP: Send message is a (more meaningful) synonym for Go
• Garbage Collection: Debug(1,1) shows object types in listing, where recognised.

Bugs Fixed

• UDP: memory leak when incoming packets discarded because Empty message hadn't been sent.
• FTPSERVER Protocol: runtime error when trying to create object.
• FTPCLIENT Protocol: Fix command/response sequencing error in processing of Put message.
• TCP/IP: occasional checksum computation errors.
• RandomNumberGen: seed value of 0 in the 16-bit generator generated a sequence of nothing but zero values.
• Latency: The code in some objects was hogging the CPU for more than 2ms without allowing swapping, thereby violating our internal maximum time- slice rule.

2006 09 05

Major Changes

• Send is now a message name and may not be used as an identifier (e.g. variable or procedure name) in your program.

New Features

• More Sprites: The number of sprites you may assign to the GraphicsLCD object has been increased from 128 to 256.
• Reduced 'Garbage Collection': The Debug (1...) Garbage Collector has been reduced so that it only detects and lists leaked memory blocks, and no longer has the option to delete them. See OperatingSystem.Debug in the Help File.
• "SMS" Protocol A new type of Protocol object controls the sending and receiving of SMS (Short Message Service) messages over a GSM mobile phone network. Text and binary data in both 8-bit and 16-bit formats can be exchanged. The interface uses a serial port and the standard ETSI protocols and has been tested on a Siemens MC35 GPRS/GSM terminal. The SMS protocol is documented in the Venom Help File under "Protocol" in the "Object Types" section.
• CRCGenerator Get with a buffer parameter can now use an 8-bit integer buffer as well as a text buffer.
• FileSystem: The Time message can take an integer parameter which is bit mapped code to indicate what sources to use for time and date information when updating a file directory. Bit 0 is set to use Internet time servers, bit 1 is set to use the Real time clock/calendar chip optionally fitted to the VM-1. Disabling Internet time servers is useful in the unusual case where an Ethernet connection and DNS server exist, but there is no route to the Internet.

Bugs Fixed

• ProtAnalyser: Fixed bug where GetLast didn't enable consumption of delimiters in every case.
• Buffer: Fixed bug where Remove used on buffers with fewer than 256 bytes would hang.
• The long delays in file system operations in some network setups can now be avoided by a parameter of the FileSystem Time message to prevent it from trying to get the time from an unreachable Internet time server (see New Features, above).
• FTP server: no longer gives a run time error when serving files bigger than 64k.
• HTTP server: re-instated sending of content-type header.
• CRCGenerator: Get with a buffer parameter works correctly for any size of buffer.

2006 06 01

Major Changes

• RAM Filesystem: the default format for a file listing has changed from 3 to 4, a new format which includes file times and dates.
• TCP Status message has the value 5 when a TCP protocol object is first created and no connection opened (was previously 0).
• FAT Filesystem: the numerical code for specifying directory listing formats has changed. Values 0 - 5 are unchanged. The full set of format codes is documented in the Venom help file

New Features

• SafeData: This object now supports the M24C32 and similar devices that use two-byte addresses internally. Also PRINT of a SafeData allows you to specify which data to print.
• FileSystem: A file in either type of FileSystem can take a Time message which assigns or return the file's creation time and date as an integer compatible with other Venom time and date functions.
• Read a number from a Text Buffer. You can now read a numeric value straight out of a buffer with Buffer.Value. This returns the value of the first number it finds in the text buffer, without 'Getting' any characters from the buffer. You can specify the type of number to be found by passing a prototype parameter: eg. 10 for decimal, 16 for hexadecimal and 1.0 for floating point.
• Remove text from a Text Buffer. The Remove message is the inverse of the Insert message: it will remove a section of text from any point within a Text Buffer.
• FTPClient protocol can transfer files to and from an FTP server. The protocol can also get file lists, find the current directory and navigate server directories. Active and passive transfer modes are both supported. ASCII and binary file types are supported automatically based on the Venom file type.
• FTPServer new protocol object enables the VM-1 to operate as an FTP (file transfer protocol) server. It can use RAM or FAT filesystems. Directory listing, subdirectories (on FAT FileSystem only) and file transfers in both directions are supported. Further documentation is in the Venom Help file.
• TCP Status: this message has an extra possible value. 5 means a normally closed connection and is also the status value of a TCP object before it is first opened.
• Keypad:InputBuffer - Improvement in key-detection algorithm means cleaner operation with touchscreens.
• Serial Break: There is limited provision for sending serial breaks to facilitate implementing the LIN protocol. Please contact us for details.
• VM-1e: Code in place to support the forthcoming VM-1e: a VM-1 with extended flash memory for very large (~512K) user applications.
• FileSystem (both RAM and FAT) : a directory listing with a format code of 9 produces a UNIX "ls -l" style listing.

Bugs Fixed

• HTTP: In the query string of a URL, the '+' character is now correctly converted back to an ASCII space, in compliance with the URL encoding standard.
• FAT FileSystem: if there is an interface problem (e.g. mismatch of jumper settings and software MAKE statement or a faulty memory card) the system would sometimes not detect this reliably and produce misleading error messages and wrong values from the Status and Valid messages. Those values are now correctly returned as 0 and any attempts to use the card cause a "Device Not found" error.

2006 03 22

New Features

• FileSystem: in the FAT file system, the equivalent of a Flush message is performed automatically at intervals when a file is written. By default the interval between flush operations is 10 minutes. The Flush message can be sent with an integer parameter which sets the automatic flush interval in milliseconds. The Application Note "Data Logging with the Memory Card File System" discusses related issues in some detail.

Bugs Fixed

• HTTP: if a graphics file is missing, a small "broken graphic" image is displayed in its place instead of a whole "Not Found" HTML error page as before.
• File System and HTTP: if the HTTP object finds the file media has been removed and replaced, it does not clear the "New Media" flag, allowing the Venom program to detect this condition reliably and take action to re-open any file objects that would have been killed on media removal.
• FAT FileSystem: an error in calculation of block addresses from cluster numbers resulted in corruption when more than 32Mb of file data were present. The block address is now calculated correctly.

2006 03 09

New Features

• VenomIDE extension The PROGRAM command now takes an optional third parameter: the download checksum. This is the checksum of all the characters between the PROGRAM commands, but sent ahead of the file so that the Venom can check the file integrity. If the download checksum is present, then Venom indicates whether or not the file checksum was valid at the end of the download.
  An optional, unassigned, fourth integer parameter is also allowed, for future extension.

2006 02 22

New Features

• HTTP Protocol Object. This provides support for writing a web server in Venom. See the Venom-SC help documentation for details.
• Ethernet The Ethernet protocol object's Address message can now take a first parameter with a value 'N' which assigns a name server (DNS) address, duplicating the functionality of ip.Find(0)
• FAT filesystem for MMC/SD cards: A filesystem can now be created without run-time error even if a card is not present. After a card is inserted, the first file open request will cause the card's system data to be read and the file system initialised properly.

Bugs Fixed

• UDP: use of UDP to get the time and date no longer causes a run time error.
• TCP: Fixed bugs which could cause the TCP protocol to hang when closing a connection and which could cause occasional loss of data on opening and closing connections.
• PPP: cured a run time error and a memory leak resulting in a RAM FULL error after some use.

2005 12 12

New Features

• FileSystem: a new type of FileSystem object can be created based on MMC/SD memory cards. The physical interface to the card can use either the SPI bus ports or serial port 2. The file system itself is Windows-compatible VFAT (FAT with long name support). Both FAT12 and FAT16 are supported but not FAT32.

  The new FileSystem object is fully described in the current online documentation available as a Windows help file or PDF.

2005 10 19

Major Changes

• STOP, when given an integer parameter, now takes the task ID number rather than the task's position in the task list. Task ID numbers are listed when you type CTRL-T or LIST TASK.
• CANBus is now a Venom-SC keyword. See New Features for details.

New Features

• ARRAY: Constant arrays may now take an expression for the dimension of the array, so long as this evaluates to an integer constant. e.g. ARRAY a (8 , 2*34+23). They also handle being given too much data more elegantly.
• AsynchronouSerial (ports 1 & 2): the low-level driver code has been improved so that fewer characters are transmitted after a hardware handshake input signals that transmission should stop.
• CANBus: A Beta version of a new CAN Bus object (CANBus) is included in this release. It is based on an MCP2515 device that sits on the VM-1's SPI Bus. Please ask for details if you would like to try out the driver object.
• Compiling code during program execution:
  Note: this feature is on Beta release; it is not fully tested and guaranteed but provided for use 'as-is'.
  There is now a mechanism to compile new procedures from within a running application. The source text can come from any object that returns characters from a Get message. Compilation can be done from any task (though for compiling larger procedures it is recommended that the main task be used as it has a larger stack, and it's important to make sure that the command line is not compiling at the same time as another task). This feature allows you to download new code over a comms link, or store it in a text file. The syntax for compiling is currently:

    Debug(7,obj)
  

  obj is an object containing the source for new procedures. The Debug(7...) call has to be done once for each procedure in obj.
  Note: the maximum line length allowed in Venom is 255 characters. Lines can be broken by using the '\r' (13) character. The last line should end with '\r' to make sure no attempt is made to read past the end of the object's text.
  Note: when an application is stored in flash, any newly compiled procedures will be held in RAM. New procedures will overlay existing ones. At the next startup all new procedures will be deleted and the originals will be restored from flash.
  Note: Any syntax errors that occur in the code will be sent out of the main serial port - it's best to make sure there are none before compiling code in this way. Any runtime errors that occur when accessing the object will result in a runtime error report but program execution will continue.
• Download checksum: In order to vaidate programs downloaded to the VM-1 the PROGRAM ... PROGRAM END construct will now indicate the checksum of every character received from the first line after the 'PROGRAM ... ' to the end of the 'PROGRAM END' line (including the last $0D). Line feed characters may or may not be sent by your terminal program, but will be included in the sum if they are. You can use this sum to validate the file that was downloaded by taking a checksum of the file between the correct points.
• IP Protocol object: the Time message takes an optional second parameter to specify the timeout period in milliseconds after which a value of -1 is returned if there's been no reply. The default is still 10 seconds.
• TCP Protocol object: The Timeout message now sets timeouts for operations other than receiving data, including actively opening a connection and receiving an acknowledgement after sending data.

Bugs Fixed

• Numerous bugs, mostly relating to memory management, in the TCP/IP stack have been fixed. In the Ethernet module, failure to transmit a packet, e.g. if the cable is disconnected, times out instead of waiting for ever and hanging. The system is also more stable when multiple tasks use protocol objects.

2005 03 29

Major Changes

• AUTODESTRUCT is now a keyword and cannot be used for variable names.
  In implementing this new feature it was necessary to make the .Die message fail silently when sent to an already-dead object.

New Features

• Source-file annotation: The PROGRAM construct now allows Venom-SC to annotate each procedure with its source file name and line number. The default syntax is to put
  PROGRAM "filename.ext" (i.e. the file name and optional extension)
  on the first line of each of your Venom-SC source files, and
  PROGRAM END
  after the last bit of code in each file. This allows runtime and syntax errors, etc, to list the exact position of the error in your source code.
  This new feature may be used immediately, but will be more fully exploited by the IDE we are developing for VM-1/Venom-SC. If you don't use the new syntax then the system behaves as before.
• AUTODESTRUCT: This keyword is used to designate a group of LOCAL variables to be sent the message Die when a procedure ends. This is to allow you to keep track of your temporary objects, given all the routes and mechanisms by which a procedure might end.
  All LOCAL variable declarations listed after AUTODESTRUCT within a procedure are in the auto-destruct group. When the procedure ends then each of the auto-destruct group is sent the message Die.
  AUTODESTRUCT works in conjunction with END, RETURN, CATCH/THROW, REGION/EXIT, and STOP/STOP ALL.
  If a task fails on an error (including CTRL-C Break), no auto-destruction takes place.
• User fonts: Proportional user-defined fonts may now be added to the GraphicsLCD object.
• Number font: FONT 4 is a copy of FONT 2, only with reduced width so that numbers are printed more pleasingly. It is intended only for printing numbers. Printing other characters will work if they have a width of 10 pixels or less. Printing wider characters may not work perfectly.
• SerialIO: A block transfer option is available to transmit and receive blocks of byte data to and from the VM-1's SPI bus.
• GraphicsLCD: A new Graphics LCD is now supported: TMGG13264-09 made by TRI-T. This is connected to the VM-1's second serial port (used in synchronous mode) via 5V to 3V logic level shifters.

2004 12 22

Major Changes

• Ethernet: this version of the code supports Issue B of the 5810 Ethernet interface module and is incompatible with 5810 Issue A.
• Ethernet and QVGA
  The 'select' parameter in the Ethernet and QVGA MAKE statements is now a 4 bit number (0 to 15) representing the bit pattern in channels 34-37 to select i.e. it is shifted down 4 bits from the value previously used.

New Features

• GraphicsLCD and Ethernet: the QVGA and Ethernet code have been modified so that the two modules (which share I/O lines) can be used concurrently.

2004 10 27

Major Changes

• Status is now a message name and cannot be used as an identifier, e.g. a variable or procedure name.
• GraphicsLCD: Printing has been completely re-written to remove bugs. The code should work very similarly to before, but there is the possibility of new bugs or differences in detail that could break applications. Check your code works if you are rebuilding with this release.

New Features

• Protocol: a TCP object now accepts a Status message which is useful especially after an active Open has failed. Status values are: 0 - OK, 1 - destination unreachable, 2 - timeout.
• Protocol: a routing failure either in the VM-1 or reported back from the Internet (ICMP "destination unreachable" code) will be detected and reported back to to the originating protocol which can handle the information intelligently instead of simply timing out. In particular, TCP will respond to this by closing the connection and returning a Status value of 1 (see above).
• Protocol: TCP Put(buffer or array)
  An undocumented limitation has been removed, whereby no more than 256 characters in a buffer could be sent using the Put message. Additionally tcp.Put can be used with arrays and buffers of any data type. Performance has been greatly improved with all forms of tcp.put and PRINT to tcp.
• Protocol: A new Ethernet Protocol object controls the 5811 Ethernet interface module or compatible hardware and provides IP connectivity though Ethernet. Mapping of Ethernet addresses and IP addresses is done transparently with ARP (Address Resolution protocol). Support is provided for LAN gateways to other networks on specific address ranges or a default gateway to the rest of the Internet.
• GraphicsLCD: Inline font changes within a single PRINT statement are handled better, so that each line has the correct amount of height and depth to accommodate the highest and deepest fonts.
• GraphicsLCD: GOTOXY(x,-y) scrolls a window up by y pixel lines.
• GraphicsLCD: User defined fonts have an extra parameter that specifies the number of blank lines, printed above the characters, separating lines of text.

2004 05 18

Major Changes

• Timer: When printing Timer objects, the second parameter no longer specifies that the period should be printed. This function has moved to the third parameter. The second parameter now specifies the number of decimal digits that should be printed for fractions of a second. If zero (0) is supplied for the second parameter then no digits or decimal point are printed.
  I.e. old code
  PRINT tmr : n : 1
  should now be
  PRINT tmr : n : 0 : 1
• Keypad:InputBuffer: The timing of the Auto Repeat function has changed slightly to fix a bug: the repeat delay is now correctly set at the parameter value (the repeat period was being added to it).
• Address is now reserved as a message name and cannot be used as an identifier, e.g. a variable or procedure name.
• NumberReader: functionality has been improved, which should improve all applications but it's possible may break some: See New Features below.

New Features

• QVGA: The VM-1 can now drive QVGA LCDs via an S1D13705 LCD controller. Both this IC and the TSC2003 Touch Screen Controller are incorporated on the new QVGA module (Product Code 5809).
• TouchScreen: This object drives a resistive touch screen via a TSC2003 IC on the I2C Bus. As well as detecting where a touch to the screen occurs (calibrated to LCD coordinates) it allows you to define virtual keys to create any style of keypad on your user interface.
• Error Redirection: It is now possible to redirect runtime error text to any object capable of accepting PRINT. For example you can redirect error text to a file. It is usual to use the 'maximum size' option for error logging files. For example:
  system . Output(1) := err_file ; Redirect err output to err_file.
  Note that if the object is locked by another task then the task with the error will stall, and no error output will be seen. At startup the error output defaults to the system object. This has the effect of streaming error output directly to the main serial port without respecting the locks on the serial object.
• Buffer has a new message: GetLast. This removes the last element from the end of the buffer and returns it. This can be used to delete characters from the end of a text buffer, or to implement a 'stack' using Put to push data onto the stack and GetLast to pull it off.
• Keypad:Inputbuffer now takes Period and Time messages. Period allows the auto-repeat period to be set (and read), and Time gives the amount of time a key has been continuously held down. These two may be used to implement an accelerating auto-repeat function.
• Keypad now takes the Key message: return the value of the key currently being pressed, or -1 if no key.
• Timer and StopWatch can now print fractions of a second in their standard print formats. To use this feature, use a second colon parameter that specifies the number of digits to print after a decimal point. If the second parameter is zero, no decimal point or fraction digits are printed. The following example prints a timer that has 5.742 seconds left to run in a minutes, seconds and milliseconds format:
-->PRINT tmr :2 :3
00:05.742

• Task objects now take the message Done, which indicates when a task is no longer running.
• New object: RandomNumberGen can create pseudo random number sequences or either 16-bit or 32-bit numbers. The 16-bit sequence is similar to the rand() function provided in many C libraries, with a sequence length of 2¹⁶ - 1. i.e. each number appears once in the sequence. The slightly slower 32 bit sequence passes standard statistical tests and has a sequence length estimated at 2⁹⁰. Both produce numbers with a flat distribution which can be constrained to a specified range, and there is also a float generator that can produce floats between -1.0 and +1.0. All can be seeded to start the sequence at a repeatable point.
• New object: CRCGenerator. 16- and 32- bit CRC generators can be made and used in a variety of ways. The 16-bit CRC uses the CCITT-16 algorithm.
• NumberReader. Improvements have been made:
  • The Minus key may be used to negate the number at any point during number entry, not just at the start.
  • If the Minus and/or Decimal Point keys are defined then the number of numeric digits is limited so there is always room to put in the '-' and/or '.'.
  • The first digit key pressed will clear the default text from the display unless the Delete key has been pressed first, in which case the number may be edited digit by digit.
  See the most recent Object Reference Manual for example usage.
• ProtAnalyser: GetLast message added; when GetLast := TRUE delimiter characters are consumed when reading numbers and strings. Default is FALSE.
• GraphicsLCD Windows: The Value message returns the text cursor position. Value(0) is the x position and Value(1) is the Y position.
• Garbage collection: As an aid to debugging a 'garbage' detection and collection system has been added to the operating system.
  During normal operation of both the Venom-SC compiler and your application, memory is requested from, and later returned to, the memory management system or 'Heap'. However, in some circumstances memory can be lost. This kind of bug can be latent in your application, only showing itself after the system has been running for some time.
  The most common cause of this kind of 'memory leak' is when you create a temporary object that needs memory (within a procedure, say) then forget to remove it (with .Die) before returning from the procedure. If you do this enough times then the system will eventually run out of memory.
  You might consider running the garbage collector on your application after it has been working a while as part of your code validation process.
  The Garbage Collection system is currently implemented as a Debug message:
  Debug(1 , flags)
  Where the optional parameter flags is a set of binary bit values which may be combined:
  1: Recover lost memory blocks
  2: Dump details of the lost memory to the main serial port
  Debug (1, ...) always returns the number of blocks of lost memory it found. If you think that it is possible that your application could be losing memory then inspecting the value of Debug(1) will let you know.
  Note: There are currently three legitimate ways of losing memory:
  i) Entering a command at the --> prompt that contains a string constant (e.g. --> PRINT "a string" , CR)
  ii) CTRL-C breaking out of a program while it is running - any temporary objects that were held in local variables will show up as garbage as even if you wrote code to destroy them after use, this won't have been called.
  iii) CTRL-C breaking out of a procedure definition part way through.
  Make sure that none of these is giving you false indications of a leak.
  Also note that Debug(1...) will NOT respect task swap timing, so don't use it as part of a normal application unless you take this into account.
• Protocol - The Address message to an IP protocol object is a preferred synonym for Value. The message's functionality is enhanced to associate symbolic names with IP addresses. e.g.
  ip.Address("server") := "192.168.1.1" will assign the address so the name "server" can be used anywhere an IP address or domain name could be used.
  ip.Address("server") will return the IP address as an integer. Unlike DNS lookups, these address entries do not expire and do not require an external DNS. They are intended for use on local networks.

2004 03 04

Major Changes

• File System: PRINT f where f is a text file used to attempt to convert UNIX-style line endings (ASCII LF character only) into CRLF. It is now guaranteed to pass all characters unchanged. The old behaviour can be invoked when printing a whole file by a special colon operator PRINT f:"+". Files created by PRINT TO f, ... CR are unaffected by this change.

New Features

• XMODEM Protocol object: CRC mode is supported and used by default for both transmit and receive, with automatic fallback to checksum if that's the only version supported at the other end of the link. The XMODEM protocol's error recovery is more robust than before, in both CRC and checksum mode.
• FileSystem: PRINT f:"+" on a text file will strip all occurrences of chr 13 (CR) and convert all occurrences of CHR 10 (LF) to CRLF, i.e. converts from Unix to DOS/Windows format.
  PRINT f:"-" will strip all CR (CHR 13) characters, thus converting from DOS/Windows to UNIX format.

Bugs Fixed

• Buffer Objects: when freeing any kind of buffer using the Die message, not all the memory was freed. If buffers were created and then killed repeatedly, eventually there would be a RAM FULL run time error.

2004 01 08

New Features

• The SerialIO object can now take a second parameter that specifies the channel to be used for the CS\ function. Currently only '8' (the existing default CS\) and '0' are supported. If you use the value '0' then no channel is used for CS\. This is useful for when multiple digital channels are used to select different devices. In this case you can use Digital.On, etc, to control the CS\ function.
• The ProtAnalyser object now supports a Reset message. Normally after a token has been read from a buffer, the ProtAnalyser caches the next character (the one that terminated the previous token). The Reset message causes it to forget the cached character forcing it to re-read the buffer. This is desirable in the common case where the buffer has been refilled and reset and parsing is to start from the beginning again.

2003 10 08

New Features

• A New Protocol type XMODEM has been introduced, which will allow data to to be transferred between the VM-1 and a file on a remote computer via either hardware serial port. Full description in the XMODEM section of the Venom-SC Help File.
• FileSystem: A variation on the file Put and Get messages transfers a whole file between a VM-1 file and a remote computer via the serial port.

2003 09 30

Major Changes

• The name 'LF' is now used for indicating a Line Feed with in the PRINT command, and so cannot now be used as a variable name.

New Features

• New serial port: there is now a beta-release of a third serial port running at up to 9600bd. Please contact us for details.
• I2C: the I2CBus object will now do a Repeated Start when '.On' is issued without '.Off' first.
• GraphicsLCD: two more GraphicsLCD drivers added for LM4064 (100x64 dot) and LM4032 (202x32 dot).

2003 08 20

New Features

• Venom now has a new protocolanalyser object, ProtAnalyser, that assembles numbers and/or characters (received via other objects) in a variety of formats.
• There is now no limit to the number of global variables allowed in a program.
• File System has block read and write operations f.Get(a) and f.Put(a) where f is a file and a is an array of the same data type. These are the fastest way to move data in and out of a file, but only work with arrays.
• File system has a new file data type for RLC (run length compressed) data. Block reads and writes between arrays of byte data and RLC files will compress the data when it contains consecutive runs of the same byte value. Large graphics LCD bitmaps are expected to benefit from this type of compression.
• The file Length message has an optional parameter. If f is an RLC file, f.Length(0) will return the size of the data represented by a compressed block, instead of the actual file size.

2003 07 14

New Features

• Venom now has a family of Protocol objects that provide a programming interface to a TCP/IP stack. This first release supports:
  • Dialup connections via a serial port and modem or GPRS
  • UDP datagrams
  • General TCP/IP connections as passive listener or active initiator
  • Sending and receiving email
  • Automatic domain name resolution
  • A facility for getting accurate time of day information
  Full venom programmer's documentation is at http://www.microrobotics.co.uk/docs/pdf/44307-netguide.pdf
• The PRINT keyword BS now prints a backspace on output devices that can support it.
• The maximum number of global variables has been raised to 1124 as a temporary measure. Eventually the number of globals will become unlimited.

2003 05 08

Major Changes

• The character constant '\' is now illegal and should instead be written '\\'.

New Features

• There is now the option to use C-style print formatting of Venom variables by using a colon followed by the printf() format string. The string must start with 'C' or 'c' to inform Venom that it is a C- style format. 'C' indicates that the variable will be seen as a long, float or pointer, whereas 'c' indicates will be seen as an int or char. For example
  PRINT 123.45 : "CThe offset was %+9.3fmm"
The offset was +123.450mm-->
• Escape codes for Alert, Backspace, Form Feed, Newline, Carriage Return, Horizontal Tab and Vertical Tab have been added to string constants. They are inserted with the sequences \a \b \f \n \r \t and \v. Similarly, character constants now accept '\a' etc. To get the character constant for a single quote use '\''. To get the character constant for backslash use '\\'.

2003 03 31

New Features

• FrequencyIn: This new object allows the measurement of frequencies to arbitrary precision, typically 0.1ppm. Accuracy is governed by the clock source used, typically 30ppm when using the internal clock.
• TYPEOF <expression>: this new operator returns the type of any expression.
• AsynchronousSerial now has a Format that sets and requires parity bits to be 0.
• Better 'ram full' error response: all incidences of ram full while running application code result in a RAM FULL error. Ram full when compiling code will abort the compilation with a message to the terminal.

2002 12 04

New Features

• 12x4 Keypad configuration implemented.

2002 11 28

Major Changes

• If you send a CTRL-T (character 20) to the main serial port it will cause a LIST TASK to be executed, listing out the task details to the serial port. This may be switched off using serial.Escape.

New Features

• [Beta release of application area dump and load using Motorola S- Records].
• Protect(0) now also erases all traces of the old application leaving the symbol table and heap clear.
• There is now no limit, other than the memory used, to the number of tasks that may be started. However, it is still a good idea not to use more than four or so unless there is a good reason to do so.
• LIST TASK will now report where - exactly - in the code each task is.
• CTRL-T will do a LIST TASK so you can see where all the tasks are, including the main task, at any time. This feature is turned on and off with Serial.Escape.

2002 11 20

Major Changes

• The RealTimeClock and DateTime objects will now give an error if a 'bad date' is printed to them, i.e. the text isn't in a format they can accept as a date.

2002 11 13

New Features

• Analogue and AlphaLCD objects can now be created on the second IIC bus.
• PulseWidthOut now has Asserted and NotAsserted messages.
• TestLock messages implemented for lockable objects.
• Default lock behaviour implemented for non-locking objects.
• Find message implemented for FileSystem.
• Check now made to ensure existence of valid Startup routine.

2002 10 16

New Features

• FileSystem object supports Name message to change name of a file
• File object supports Name message to return or change the name of a file
• FileSystem Open message has optional third parameter to set maximum file size - writing past this size causes oldest data to be removed from file.
• FileSystem Reset message runs a file system check and forces closed any open files
• FileSystem updated temporary documentation at http://www.microrobotics.co.uk/FileSystem.html
• User-defined fonts can now be created for the GraphicsLCD.
• Macros (#DEFINE) are now a full part of the language. See the latest manuals for details.
• DateTime now has a Nudge message that facilitates digital-watch style date entry, a Valid message for detecting invalid dates, and new PRINT formatting allowing invalid dates to be printed.
• A new SafeData object has been implemented that allows storage of non-volatile parameters in EEPROM and other devices.
• Valid and Checksum messages may be used to validate the Venom-SC system code.
• AsynchronousSerial Valid message reports serial receive errors.
• HELP has been improved - can now take any keyword or symbol, as well as global variables. Help on keywords and symbols is limited.
• The Output message to the OperatingSystem allows redirection of the default output text from PRINT, LIST and HELP:
  Output : = <new output stream>

2002 08 15

Major Changes

• The RealTimeClock alarm function has been improved. The only messages that affect the alarm are now On, Off and SleepUntil. If you are using the RealTimeClock for controlling the power to your application, you may need to put in a line that explicitly turns the clock alarm function on, as MAKE RealTimeClock no longer does this.
• A new message name 'Name' has been added to the Venom-SC system. If you have any variables or procedures that are called 'name' then you will need to change them to something else.

New Features

• GraphicsLCD Accept Print message now allows sprites to be incorporated into text strings by including \^xx in the text string. (xx is the sprite number represented as 2-digit hexadecimal digits). For example the following would write 'café au lait' to the graphics LCD provided that an e with an acute accent had been previously defined as sprite number 3.
  PRINT TO obj,"caf\^03 au lait"

2002 07 29

New Features

• Software handshaking on the serial ports. Use '2' for the handshake parameter in MAKE or
  serial.Handshake := 2.
• Non-volatile arrays:
  You can now put Arrays in the NV-RAM to store non-volatile parameters etc.
  nv_array := an_array.
  Copy(1) creates an 'overlay' copy of an existing Array in the non-volatile RAM area: the data is not copied, just the header information. To complement this, you can use the Checksum and Valid messages to validate the contents of any array. See the Object Reference for details.
• CTRL-C on an empty command line will now stop background tasks running, if any were active. It prints STOP ALL to let you know this has happened.
• PulseCounter ON and OFF messages implemented; and the count can now be set.

2002 07 18

New Features

• Dallas 1-Wire bus driver object 'OneWire' enables VM-1 to communicate with Dallas iButtons and other 1-Wire devices.

2002 07 09

New Features

• File system: print fs:0 (where fs is a FileSystem object) no longer inserts padding spaces.
• File system: print fs:0:string uses the string instead of new line as a file name separator

2002 06 27

Major Changes

• MAKE fs FileSystem("RAM", size) The FileSystem size parameter is now in bytes instead of kilobytes.

New Features

• File system: The colon operator is supported when printing files of all types
• File system: A size vale of 0 in MAKE FileSystem will find the existing file system (if any) and use it. Only recommended for command line use when file system size was unknown.
• HELP file shows file name
• file.Find message is now supported, similar to buffer.Find
• file.Readpoint message is now supported, similar to buffer.Readpoint
• File System Performance improvements.
• Updated documentation for the file system remains available at http://www.microrobotics.co.uk/fs-beta.html

2002 06 19

New Features

• A beta test version of the file system is available. The file system is based on non-volatile ramdisk. It supports many of the same messages as the Buffer class. Temporary documentation is at: http://www.microrobotics.co.uk/fs-beta.html. To use the file system the advice above regarding the init procedure should be modified: The Free(2) line should read: Free (2) := 50000 for example, to reserve 50000 bytes of memory for use by the file system. The file system is incomplete and some messages are not implemented yet.

2002 06 12

Major Changes

• For maximum security the line Free (2) := 0 should be included early in the init procedure of every application to make sure that the memory system is set up correctly. If this line is missing there is a very small chance that the system could start with a small (down to 20K) amount of heap memory, rather than the usual ~100 or ~500K. See Free in New Features 2002 06 19.

New Features

• The Flash Programmer socket on the new 5805 'Breakout Board' is now supported. You can use it copy the entire contents of the system flash to the external flash. You can also program the external flash with new versions of Venom-SC downloaded from our web site in S-Record format. The syntax of the flash programming commands is:

          Copy(0,flags) ; copy the system flash
          Copy(1,flags) ; download S-Record file
          

  The instructions and progress reports for each operation will appear at the terminal. The flags parameter is a binary pattern that tells the Copy message which optional operations to perform in sequence. In general use a value of TRUE for the most comprehensive operation: Copy(0,TRUE) ; ID, erase, program, verify.

          Flag  Value Action
          ID  1 Print 'Silicon signature' ID
          ERASE 2 Erase the device
          PROGRAM 4 Program the device
          VERIFY  8 Verify the program
          

  Important note: currently, if the device has not been correctly erased before programming, then the copy or download operation will fail ungracefully. The controller will reset on the watchdog. You will probably have to reset the controller and you may have to exit from the terminal emulator.
• The memory management has been extended. There is now an area of non-volatile RAM (NV RAM) that is not part of the main heap memory of the controller. This is intended for the forthcoming RAM filing system, though it may have other uses later. To set the NV RAM size, see System.Free below.
• System.Free has now been extended with an optional parameter: Free ; returns the total heap memory free, as before.
  Free (0) ; (same as above)
  Free (1) ; returns largest heap block.
  Free (2) ; returns total size of the NV RAM.
  Free (3) ; returns remaining amount of NV RAM.
  Also, Free may be used to set the size of the NV RAM:
  Free(2) := Note that if the NV RAM size is changed then the controller will reset. For system security, Free(2) should be set to a constant value in your init procedure to make sure the system heap is a consistent size. For applications where NV RAM is not required (e.g. you don't have a RAM filing system), just use Free(2) := 0.
• GraphicsLCD:Window active object DISPLAY and Marker now implemented. Display is not a print keyword, but a message to a GraphicsLCD Window. disp_obj := win . Display(@variable , fmt1 , fmt2, fmt3) The fmt parameters are format descriptors with the same values as you would use after the colons in the PRINT command. The number of formats is optional from zero to three.

2002 05 07

Major Changes

• See AsynchronousSerial in New Features 2002 05 07.

New Features

• AsynchronousSerial now has optional hardware handshaking. To retain handshaking the MAKE should have a 3rd parameter of value '1'. The default startup procedure has been altered to reflect this. You may need to alter your code too.

2002 05 01

New Features

• Array MAKE: Arrays may now be created dynamically with MAKE or NEW as well as statically. This allows arrays of read/write data to be created dynamically, or to have large arrays without having to have large amounts of initialisation data in ROM.
• GraphicsLCD:Window Bar is now implemented.

2002 04 18

Major Changes

• The 'Trigger' message has been changed to 'Go' for all objects that used it.
• The PulsesIn class name has been changed to PulseCounter.
• The old, undocumented method of introducing a double quote character into a string constant has been superseded. It used to be "" but is now \".
• The GraphicsLCD Sprite message now requires the user to assign a number to each sprite. Macros can be used to do this if required. E.g.:
  #define TRIANGLE 0
g.sprite (TRIANGLE) := (a.pointer)
• GraphicsLCD: can now be created using 1 or 3 parameters (specifying dimensions).

New Features

• Object printing: Many objects that used to print themselves just as a plain number now put [] round the number to provide a hint that they are not just an integer. Of course you can still print just the number by printing the value of a message sent to the object.
• RealTimeClock: The SleepUntil message will now control the clock's alarm output to enable zero-power sleeping. The alarm line may also be controlled directly with On and Off. clock . SleepUntil(time) ; Time: absolute time in seconds.
• GraphicsLCD: LEFT, RIGHT and CENTRE text justification now available.
• GraphicsLCD: Graticule now implemented.
• NOP: this new keyword compiles to a 'no operation' bytecode, i.e. it does nothing.
• Escape codes have been introduced into string constants. The escape character is \.
  
  • \\ gives \
  • \" gives a quote character
  • \$hh where hh is two hex digits (case insensitive) introduces any ASCII character into the string.
  • \ with any other character is completely ignored.
• To complement the macros, constant folding in the compiler has been extended. It now folds both floating point and integer operations for most of the operators, both unary (one operand) and binary (two operands). Constant folding does not yet cover the following operations:
  • Equality operators: = >< >= <=
  • Type conversion: AS INT, AS FLOAT
  • ABS, all trigonometric, EXP, LOG, SQRT functions.
  These will be implemented when demanded.
• AsynchronousSerial: the messages InputBuffer, OutputBuffer, Look, Queue, Flush, Free, Format and Escape have been added.
• A 'Done' message has been added to Timer.