K4S is now obsolete

Many more functions may be added to the K4S via the I2C bus, Expansion Bus, and the Microwire Bus. These are described in detail on this page.
Hardware support for some of the interfaces described here is provided by our range of Application Boards or can be implemented on the customer's own hardware.

The I2C bus is a two-wire network which can control many devices.
On the K4S, the I2C bus makes available the following functions, which are not part of the basic K4S hardware but available as expansion options and supported by the software.

• 128 digital I/O channels.
• 32 analogue inputs channels and 8 analogue output channels (8 bit resolution).
• A real time clock/calendar.
• A teletext video display.
• The language also supports a parallel printer, alphanumeric LCDs and keypads, all based on I2C Digital I/O channels.

This is an IC that can be plugged directly into a socket on the K4S. It uses on-board I2C bus. The language supports this device over dates ranging from 00:00:00 on January 1st 1990 until the year 2024, taking account of leap years. The K4's on-board battery keeps the clock's date and time correct even when the unit is unpowered.

These Micro-Robotics hardware products are intended for interfacing low level signals inside an equipment housing. They may be connected to the K4S or any controller with an I2C bus. The K4S provides full software support.

Up to four of these I2C cards can be connected, each fitted with 16 TTL digital I/O channels, together with prototyping area.

Up to four of these may be connected, each with 8 analogue inputs (8 bit, 0-5V) and two analogue outputs (8 bit, 0-5V).

An I2C board suitable for driving many different parallel printers. This board uses 16 of the 128 available digital channels.
The language also provides direct access to the I2C bus so that unsupported devices may be controlled.

The K4S supports the industry standard Microwire/SPI bus which can be used to control a host of high resolution analogue input and output devices.

This is the K4S's raw processor bus, running at ~2.4 MHz, to which the UPP, Expansion Bus and other devices may be attached.

This is a software-controlled I/O expansion port made by the addition of a few cheap ICs, attached to the system bus. It allows a graphics LCD and large keypad to be attached to the K4S. It will also drive alphanumeric LCDs.