[SOLVED] arduino uno i2c communication

[kunal123]

hello,
i refeere following tutorial for i2c communication between push button & arduino uno using pcf8574p i/o expander for i2c bus
**broken link removed**

i receive the data from slave device is 11111111 in binary, i think this is the status of P0 to P7

then i remove all the inputs means push button input connected to pcf8574's (P0 to P7 pin), it again receive the data from slave device is 11111111 in binary, status of P0 to P7.

i think i give address of slave device is wrong.

how i can get correct slave device address

thanks & regards

 

[mrflibble]

Without too much reading of details ... In general some I2C device datasheets are a bit confusing, and you'll have to left shift the listed base address by 1 bit. I ran into one of those the other day. Always a fun way to waste an hour. >_<