BS2 Sonar SRF08
Tento program meria vzdialenosť senzorom SRF08 a vypisuje hodnoty na sériový LCD displej a zároveň posiela cez USB/RS-232 do PC, kde sa dá zobraziť v terminálovom okne.
Pripojenie
SRF08: SCL CON 9 ' I2C clock SDA CON 8 ' I2C data LCD Backpack: LCD CON 0 ' LCD Serial Backapck Data Line
'{$STAMP BS2}
SCL CON 9 ' I2C clock SDA CON 8 ' I2C data LCD CON 0 ' LCD Serial Backapck Data Line SDAin VAR IN8 SDAout VAR OUT8 ' To change the pins used, alter these 5 lines SDAdir VAR DIR8 ' The 4 SDA numbers must be the same, of course
loop VAR Byte ' just a looping counter I2cBuf VAR Byte ' I2c read/write buffer I2cAddr VAR Byte ' Address of I2C device I2cReg VAR Byte ' Register number within I2C device I2cData VAR Word ' Data to read/write I2cAck VAR Bit ' Acknowledge bit
' LCD: Defining some useful constants for the Backpack.
N9600 CON $4054 ' Baudmode-9600 bps inverted.
I CON 254 ' Instruction prefix value. CLR CON 1 ' LCD clear-screen instruction.
LINE2 CON 192 ' Address of 1st char of 2nd line. L1_C7 CON 135 ' Address of line 1, character 7. L2_C7 CON 199 ' Address of line 1, character 7.
SEROUT 0,N9600,[I,CLR] ' Clear the LCD screen. SEROUT 0,N9600,["Range:"] ' Print the label.
Main:
I2cAddr = $e0 I2cData = 81 ' Rangeing command - 80 for inches, 81 for cm, 82 for uS
I2cReg = 0 GOSUB I2cByteWrite PAUSE 70 ' Wait for ranging to complete
I2cReg = 1 ' Address of light sensor register GOSUB I2cByteRead DEBUG 2,0,0, "Light Sensor ", DEC3 I2cData, " u"
I2cReg = 2 ' address of first ranging result GOSUB I2cWordRead DEBUG 2,0,1, "Range ", DEC4 I2cData, " cm" SEROUT 0,N9600,[I,L1_C7] ' Move to line 1, character 7. SEROUT 0,N9600,[DEC4 I2cData, " cm"] ' Print message.
' --------------------------------------------------------------------------------------------
I2cData = 82 ' Rangeing command - 80 for inches, 81 for cm, 82 for uS
I2cReg = 0 GOSUB I2cByteWrite PAUSE 70 ' Wait for ranging to complete
I2cReg = 2 ' address of first ranging result GOSUB I2cWordRead DEBUG 2,0,2, "Range ", DEC4 I2cData, " us" SEROUT 0,N9600,[I,L2_C7] ' Move to line 1, character 7. SEROUT 0,N9600,[DEC4 I2cData, " us"] ' Print message.
GOTO main
'--------------------------------------------------------------------------------------------
' I2C subroutines follow
'--------------------------------------------------------------------------------------------
I2cByteWrite: ' writes I2cData.lowbyte to I2cReg at I2cAddr
GOSUB I2cStart I2cBuf = I2cAddr GOSUB I2cOutByte ' send device address I2cBuf = I2cReg GOSUB I2cOutByte ' send register number I2cBuf = I2cData.LOWBYTE GOSUB I2cOutByte ' send the data GOSUB I2cStop RETURN
I2cWordWrite: ' writes I2cData to I2cReg at I2cAddr
GOSUB I2cStart I2cBuf = I2cAddr GOSUB I2cOutByte ' send device address I2cBuf = I2cReg GOSUB I2cOutByte ' send register number I2cBuf = I2cData.HIGHBYTE GOSUB I2cOutByte ' send the data - high byte I2cBuf = I2cData.LOWBYTE GOSUB I2cOutByte ' send the data - low byte GOSUB I2cStop RETURN
I2CByteRead:
GOSUB I2cStart I2cBuf = I2cAddr GOSUB I2cOutByte ' send device address I2cBuf = I2cReg GOSUB I2cOutByte ' send register number GOSUB I2cStart ' repeated start I2cBuf = I2cAddr | 1 GOSUB I2cOutByte ' send device address (with read set) I2cAck = 0 ' send Nak GOSUB I2cInByte I2cData.LOWBYTE = I2cBuf ' read the data I2cData.HIGHBYTE = 0 GOSUB I2cStop RETURN
I2CWordRead:
GOSUB I2cStart I2cBuf = I2cAddr GOSUB I2cOutByte ' send device address I2cBuf = I2cReg GOSUB I2cOutByte ' send register number GOSUB I2cStart ' repeated start I2cBuf = I2cAddr | 1 I2cAck = 1 ' send Ack GOSUB I2cOutByte ' send device address (with read set) GOSUB I2cInByte I2cData.HIGHBYTE = I2cBuf ' read the data I2cAck = 0 ' send Nak GOSUB I2cInByte I2cData.LOWBYTE = I2cBuf GOSUB I2cStop RETURN
I2cOutByte:
SHIFTOUT SDA, SCL, MSBFIRST, [I2cBuf] INPUT SDA HIGH SCL ' clock in the ack' bit LOW SCL RETURN
I2cInByte:
SHIFTIN SDA, SCL, MSBPRE, [I2cBuf] SDAout = 0 SDAdir = I2cAck HIGH SCL ' clock out the ack' bit LOW SCL INPUT SDA RETURN
I2cStart ' I2C start bit sequence
HIGH SDA HIGH SCL LOW SDA LOW SCL RETURN
I2cStop: ' I2C stop bit sequence
LOW SDA HIGH SCL HIGH SDA RETURN