'-------------------------------------------------------------------------------
'                              starter.bas
'       this is an example for readining a SFR08 sonar
'                    all output will be on com2
'     There is also an LED on portB.0 that will light if the
'          distance reading is lower then 6 inches
'-------------------------------------------------------------------------------


$crystal = 14745600
$regfile = "m128def.dat"
$baud1 = 19200
'$sim

'config serial buffer
Config Serialout1 = Buffered , Size = 40
Config Serialin1 = Buffered , Size = 40

'com 2 standard conection
Config Com2 = Dummy , Synchrone = 0 , Parity = None , Stopbits = 1 , Databits = 8 , Clockpol = 0

'config  I2C lines for mavric
Config Sda = Portd.1
Config Scl = Portd.0

'this function is used to read the sonar value
'declare Functons
Declare Function I2cread8_w(byval I2cnode As Byte , Byval Loc As Byte) As Word

'this sub starts the PING of all conected sonars
'Declare Subs
Declare Sub I2cwrite8_b(byval I2cnode As Byte , Byval Loc As Byte , Byval Value As Byte)


'  Startup int code
I2cinit                                                     'start the I2C buss
Open "com2:" For Random As #2                               'open come port
Enable Interrupts                                           'enable interupts
Config Portb = Output
Portb = 0                                                   'set all low

'varables
Dim Distance As Word                                        'varable to hold sonar value
Const Sonar1 = 226                                          'make address of sonar

'start main program
Do
   'small delay of 500mS
   Waitms 500
    Call I2cwrite8_b(0 , 0 , 80)                            'ping all sonars and return value in inches
   Waitms 70                                                'delay 70mS for all pings to hapen
   Distance = I2cread8_w(sonar1 , 2)                        'read the distance from node 226 and loactions 2 & 3
   Print #2 , "Distance = " + Str(distance) + Chr(10) + Chr(13)       'send distance out com port
   If Distance <= 6 Then                                    'check distance on sonar reading
      Portb.0 = 1                                           ' less then 6 inch then led ON
      Print #2 , "LED on" + Chr(10) + Chr(13)
   Else
      Portb.0 = 0                                           ' greater then 6 inch then led OFF
      Print #2 , "LED off" + Chr(10) + Chr(13)
   End If
   Print #2 , "" + Chr(10) + Chr(13)                        'blank print to seperate readings
   Waitms 500                                               'wait 500mS and start again
Loop
'end main program

'subs
'------------------------------    I2C    I2C    I2C    I2C    I2C    I2C    I2C    I2C    I2C    I2C    I2C
Sub I2cwrite8_b(byval I2cnode As Byte , Loc As Byte , Value As Byte)
    I2cstart
    I2cwbyte I2cnode
    I2cwbyte Loc
    I2cwbyte Value
    I2cstop
    Waitms 10
End Sub
'-----------------------------------------------------------------------------
'8x16
Function I2cread8_w(byval I2cnode As Byte , Loc As Byte) As Word
  Local Lsb As Byte
  Local Msb As Byte
  I2cstart
  I2cwbyte I2cnode
  I2cwbyte Loc
  I2cstart
  Incr I2cnode
  I2cwbyte I2cnode
  I2crbyte Msb , Ack
  I2crbyte Lsb , Nack
  I2cstop
  I2cread8_w = Makeint(lsb , Msb)
End Function