; Date: 18/06/2008
; Here are some code fragments that will drive the devices on the 5624 Analogue I/O port.
; They assume default I2C Bus addresses.

;Set up the ADCs. Call this before trying to read the ADCs.
TO init
  ;Make one object that can read any of the 8 12-bit channels:
  MAKE adc12 Analogue(0,1,64,0) ; (Type, I2C Bus, Address, Channel)
  ;Set up the 18-bit ADC at 16-bit; no driver object is available.
  setup_adc16
END

;Set one or both of the DAC outputs.
; Chan is 1 or 2, or 3 for both.
; Val is 0-4095.
TO set_dac(chan,val)
  net.On
  net.Put(24);Chip address
  net.Put(chan) ;DAC channel(s) to address.
  net.Put(%00100000 + val DIV 256 ) ; control bits + Value MSbits
  net.Put(val) ;Value LSB - no need to mask high bits.
  net.Off
END

;Read a value from the 12-bit ADC
;Chan is 0-7.
;Note: don't really need to define a procedure to do this.
;Init must be called first to MAKE the ADC object.
TO read_adc12(chan)
  return adc12.Value(chan)
END

;Initialise the MCP3421 for 16-bit operation and 1:1 input PGA gain.
TO setup_adc16
  net.Lock
  net.On
  net.Put(208) ;Device address
  net.Put(%00011000);Continuous, 16-bit, 1:1 gain.
  net.Off
  net.UnLock 
END

;Read raw ADC value from the MCP3421.
;init must be called first to initialise the ADC.
TO read_adc16
  net.Lock
  net.On
  net.Put(208+1) ;Device read address.
  a := net.Get()
  b := net.GetLast()
  net.Off
  net.UnLock 
  RETURN a*256 + b
END