CGMMSTICK I2C Interface Example

As an example of the operation if the I2C function of the CGMMSTICK1, this example interfaces to a PCF8574A I/O expansion device.

I/O Pins 12 and 13 are used for I2C, as described in the documentation.

The code used in this example assumes that the address pins (A0-A2) are all grounded, giving this chip an address (offset) of 0.

The example code runs a 'cylon' pattern on the LEDs.

' Enable I2C

' speed = 100 kHz

' timeout = 100 milliseconds

I2CEN 100, 100

DO

FOR loop1 = 0 TO 7

cylon = 2^loop1

cylon = (cylon XOR &hFF)

' Send I2C command to PCF8574A

' 8574A address = &h38

' send 1 byte

I2CSEND &h38, 0, 1, cylon

PAUSE 100

NEXT loop1

FOR loop2 = 6 TO 1 STEP -1

cylon = 2^loop2

cylon = (cylon XOR &hFF)

' Send I2C command to PCF8574A

' 8574A address = &h38

' send 1 byte

I2CSEND &h38, 0, 1, cylon

PAUSE 100

NEXT loop2

LOOP

' Disable I2C

I2CDIS

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