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What is the expected behavior of the 954 when a Slave Alias and Slave ID are setup for a given port and the remote slave is not present on the other side of the remote link? The assumption is a 953 is present and the system is LOCKED, but the remote slave is not enabled or is not physically connected to the remote I2C bus. Also assume Pass Thru is enabled and Pass Thru All is not used. All remote communication to the 953 is fully functional. Also assume BCC Watchdog Control register 0x07 is left as default.
In this case, should the 954 clock stretch for 127 * 2ms = 254ms waiting for a response from the remote slave and then timeout and release the clock? I have a system where I observe both clock stretching and repeated communication attempts with the remote slave. In the case where repeated attempts are made, the time duration between attempts is relatively fast ~500us. Is it possible the 954 is not able to pull the SCLK low before the master is retrying communication? Thank you.
There are 2 different behaviors observed. In the scope plots below the traces are:
Yellow = 1V8
Blue = LOCK
Green = SCL
You can see that in one case the SCL line is held low for 254ms. I assume this is the 954 clock stretching for the entire BCC Timer period from register 0x07 of the 954. In another case with the same software initialization, there is no long duration of SCL being held low. Both cases have the same ECU with 954 but each picture has a different remote 953 camera attached. In both cases, the initialization is looking for a device that is not present in either system. However, when attempting to read status of the non-present device there are 2 different behaviors.
