Hello,
We are using in our design 2 UCD90160A PowerManager with different I2C addresses.
Our Processor P3041 supports Clock streching.
After Power up the Processor reads the device Info from both PowerManager.
We send the following commands:
1. 9D and reads 6 Bytes
2. 99 and reads 8 Bytes
3. 9C and reads 4 Bytes
4. 9B and reads 8 Bytes
5. 9A and reads 6 Bytes
In some random cases we have the problem that we get after the command 9A no response from the PowerManager.
Sometimes it is Powermanager 1 and sonetimes it is PowerManager2.
For all commands we use the same routine in Software. so we have for each command the same time.
What we also tried is to change the sequence of the commands. it means on Pos 5 we send the command 9C or 9D.
We watched that the no Response from the PowerManger comes every time (when we see an error) at Pos 5 independent from the command
After reading the device Info the processor reads 1000 times from the PowerManger without any erros (no Response).
Do you have an explanation why we get sometimes this error. When we look with the Osciloscope on the Bus the signalquality are very good.
regards
Christian Guenther