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Hello,

I have included a screen shot of what I am seeing on the HDQ interface to our battery.

First, note that I am showing a data trace at my Open-Drain TX buffer and I am showing one at the battery connection (to prove this signal is getting off my board and to the battery).  At one point I was showing my TX signal and my RX signal to show the feedback was getting to my RX buffer and that I was receiving data (I have since move that connection out to the battery to prove the signal is getting to the battery).  That is why there are two signals on the screen shot for a 1-Wire Interface.

Next, I am trying to show a ‘1’ being sent and a ‘0’ being sent.  Note:  All bit cycles are 200usec long and for the ‘1’ I was using 20usec LOW but have since change that to 40usec LOW and 160usec HIGH and for the ‘0’ I send 120usec LOW followed by 80usec HIGH.

When ever I send data I also receive data and in my code all my TX data (bytes) matches my RX data (bytes).

Not shown on the screen is a LOW pulse of 250usec to ‘sync’ the initial battery data (recommended by the battery manufacture).  That LOW 250usec pulse was about 2msec before the start of actual data to the battery.

I send a control byte to the battery (0x01) followed by several ‘0xFF’s to try and receive data from the battery.

When I first used the 20usec LOW pulse to the battery I would never received any response from the battery, but when I widened that LOW pulse on the ‘1’ from 20usec to 40usec, I started receiving some response from the battery but it was not a consistent response (usually one response in about 4 or 5 command packets).

Any help would be appreciated.  Thanks!