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badrad
- 5th October 2005, 23:06
Has any one ever tried using the PCA9555 (I2C 16 bit Remote I/O Expanders) with the PBP? I had been using the PCF8575, but due to some delivery problems, I had to substitute with PCA9555. Although pin and functionally compatible, there is a small problem with the read command. The device needs a write command then followed by a read command within the same stream.

The read command requires the following format:

Start bit, Address byte (r/w bit set to 0), Register Byte, Start Bit,
Address Byte (r/w bit set to 1), XX, XX, Stop bit.

(XX, XX is the data from the Device).

Any thoughts or experience? Thanks for any help.