' =========================================================================
'
'   File....... SW20-EX32-24LC32.BSP
'   Purpose.... I2C Interfacing
'   Author..... (C) 2000 - 2005, Parallax, Inc.
'   E-mail..... support@parallax.com
'   Started....
'   Updated.... 01 SEP 2005
'
'   {$STAMP BS2p}
'   {$PBASIC 2.5}
'
' =========================================================================


' -----[ Program Description ]---------------------------------------------
'
' This program demonstrates essential I2C interfacing by connecting to
' a 24LC32 EEPROM.


' -----[ I/O Definitions ]-------------------------------------------------

SDA             PIN     8                       ' I2C serial data line
SCL             PIN     9                       ' I2C serial clock line


' -----[ Constants ]-------------------------------------------------------

Ack             CON     0                       ' acknowledge bit
Nak             CON     1                       ' no ack bit

EE24LC32        CON     %1010 << 4              ' device ID


' -----[ Variables ]-------------------------------------------------------

slvAddr         VAR     Byte                    ' I2C slave address
devNum          VAR     Nib                     ' device number (0 - 7)
wrdAddr         VAR     Word                    ' word address

test            VAR     Nib
outVal          VAR     Byte
inVal           VAR     Byte
fails           VAR     Word


' -----[ Initialization ]--------------------------------------------------

Reset:
  #IF ($STAMP < BS2P) #THEN
    #ERROR "Please use BS2 version: SW20-EX32-24LC32.BS2"
  #ENDIF

Setup:
  devNum = %000                                 ' chip select (%000 - %111)
  slvAddr = EE24LC32 | (devNum << 1)            ' setup slave ID

  DEBUG CLS,
        "24LC32 Demo    ", CR,
        "---------------", CR,
        "Address...     ", CR,
        "Output....     ", CR,
        "Input.....     ", CR,
        "Status....     ", CR,
        "Errors....     "


' -----[ Program Code ]----------------------------------------------------

Main:
  fails = 0
  FOR wrdAddr = 0 TO 4095                       ' test all locations
    DEBUG CRSRXY, 11, 2, DEC4 wrdAddr
    FOR test = 0 TO 3                           ' use four patterns
      LOOKUP test, [$FF, $AA, $55, $00], outVal
      DEBUG CRSRXY, 11, 3, IHEX2 outVal
      I2COUT SDA, slvAddr, wrdAddr.BYTE1\wrdAddr.BYTE0, [outVal]
      PAUSE 10
      I2CIN SDA, slvAddr, wrdAddr.BYTE1\wrdAddr.BYTE0, [inVal]
      DEBUG CRSRXY, 11, 4, IHEX2 inVal,
            CRSRXY, 11, 5
      IF (inVal = outVal) THEN
        DEBUG "Pass "
      ELSE
        fails = fails + 1
        DEBUG "Fail ", CRSRXY, 11, 6, DEC fails
        EXIT                                    ' terminate location
      ENDIF
      PAUSE 10
    NEXT
  NEXT
  IF (fails = 0) THEN
    DEBUG CRSRXY, 11, 6, "None. All locations test good."
  ENDIF
  END


' -----[ Subroutines ]-----------------------------------------------------
 