Other Parts Discussed in Thread: TPS65981, USB2ANY
I am likely to need further support beyond this specific inquiry, but I am having a great deal of difficulty trying to get FTDI adapters to work with this EVM and the tool "TPS65981_2_7_8 Application Customization Tool"
Exception Encountered during I2C Test Read:*** ERROR in FTDI call (I2C_DeviceWrite), status: 2
<type 'exceptions.Exception'>
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Traceback (most recent call last):
File "dialogWindow.pyc", line 10892, in test_read
File "device_rw.pyc", line 707, in read_reg
File "hw_interface.pyc", line 417, in hw_i2c_write_no_stop
File "ftdi.pyc", line 615, in ftdi_i2c_write
Exception
The EVM board appears to have the I2C address configured with an open (no pull-down resistor), and two DBG_CTL1, and DBG_CTL2 set to 0 giving me the addresses of 0x3F for I2C1 and 0x27 for I2C2.
SPI Works whether or not I have the USB to SPI adapter plugged in to the EVM, which is a little worrisome. I cannot confirm the processor is running with the SPI behaving this way.
When I observe the I2C signals while sweeping addresses, the data and clock lines are unable to get below 1.5V as if there is contention on the bus.
The adapters I am using are Adafruit's TF232H. These included some strong 1.2K pull-ups on the I2C lines that I removed. It pulled up to 3.3V which would probably be OK, but all of the pull-ups together would have been <1K ohm.
When attempting to run the board in I2C mode, no traffic appears on the I2C bus at all upon reset or power-up. This in itself worries me this board is bad. It has never worked in I2C mode.
When running the board in non-I2C mode, no traffic appears, but I am able to get the display port from the USB-C port to work properly which was a little encouraging.
Is it likely this board has problems, and I am fighting a losing battle? I cannot see a way this contention is manifesting without there being an actual problem. What should I expect to see on the I2C bus in I2C mode when I power on the board?
Thanks,
