'*************************************************
'**LIS302DL Example Program uisng I2C for PICAXE**
'**By Hussam EL-Sheikh 6th July 2009**********
'*************************************************

symbol who = b0	'who am I
symbol dat = b1	'data ready

symbol X= w1

symbol Y= w2

symbol Z= w3

symbol TEMP = w4		'for use in calculations
symbol sign = b10		'sign byte
symbol ii = b11		'counter 
low 6 
let ii = 0
let X = 0
let Y = 0
let Z = 0
let sign = %00000000	'This is the sign byte, this is how it works: Bit0 is for the X axis
											   'Bit1 is for the Y axis
											   'Bit2 is for the Z axis
				'When the respective Bit is = 1 then the reading is negative


init:
   high 6
   hi2csetup i2cmaster, $39, i2cslow, i2cbyte	'set up the I2C protocol for the LIS302DL
   hi2cout $20, (%01000111)	'Diable power down and enable X,Y,Z axis
   pause 10

data_check:
   hi2cin $27,(dat)		'Check if new data is ready
   dat = dat | %11110111	'isolate the ZYXDA bit with bit operation
   pause 10   
   if dat = 255 then goto read_data
   goto data_check
 
   
read_data:
   hi2cin $0F,(who) 'Read who_am_i register sanity check should equal %00111011 or $3B
   
   '*************************
   hi2cin $29,(TEMP)		'Read X
   if TEMP > 127 then		'if it's negative remove the sign and raise a marker
   	 TEMP = 256 - TEMP
   	 TEMP = TEMP*18
   	 X = X + TEMP
   	 sign = sign | %00000001	'Bit operation to signal it's negative
   else
   	 TEMP = TEMP*18 
   	 X = X + TEMP
   	 sign = sign &/ %00000001	'Bit operation to clear negative signal
   endif
  '************************** 
   hi2cin $2B,(TEMP)		'Read Y
   if TEMP > 127 then		'if it's negative remove the sign and raise a marker
   	 TEMP = 256 - TEMP
   	 TEMP = TEMP*18
   	 Y = Y + TEMP
   	 sign = sign | %00000010	'Bit operation to signal it's negative
   else
   	TEMP = TEMP*18
   	Y = Y + TEMP
   	sign = sign &/ %00000010	'Bit operation to clear negative signal
   endif
   '*************************
   hi2cin $2D,(TEMP)    	'Read Z
   if TEMP > 127 then		'if it's negative remove the sign and raise a marker
   	 TEMP = 256 - TEMP
   	 TEMP = TEMP*18
   	 Z = Z + TEMP
   	 sign = sign | %00000100	'Bit operation to signal it's negative
   else
   	TEMP = TEMP*18
   	Z = Z + TEMP
   	sign = sign &/ %00000100	'Bit operation to clear negative signal
   endif
   ii = ii+1

'***************************   
   if ii = 10 then			'Take an average over 10 cycles
   	
   	ii = 0
   	X = X/10
   	Y = Y/10
   	Z = Z/10
	debug
	X = 0
	Y = 0
	Z = 0 
   endif                     

goto data_check