Dear Support Team,
I am opening new thread since this issue is not related to the thread "UART C on efusA9X with on board WLAN/BT" where we have started the discussion about it.
So, the problem is that hardware flow control is not supported at all (as it seems) by serial driver on efusA9X. Here is what I have observed while running tests on our hardware and using oscilloscope to monitor UART lines. Tests were done on UART B, using lines 102, 104, 106 and 108 on efusA9X. I have tried all variants of RTS flow control mentioned in fRtsControl member of DCB structure (RTS_CONTROL_ENABLE, RTS_CONTROL_DISABLE, RTS_CONTROL_HANDSHAKE, RTS_CONTROL_TOGGLE). No matter what flow control I used, both RTS and CTS lines were on low level all time. Serial driver does not seem to drive RTS/CTS at all. I confirm I had correct data output on Tx line during the test. Moreover, I could drive RTS/CTS manually (using ioctls from dio_sdk.h), so, I confirm that I have monitored correct lines.
I have also tried to use RS485=1 (REG_DWORD) registry value in HKLM\Drivers\BuiltIn\efusA9X\UARTx, although I am not sure what is it meant for, or if it is supported at all. It did not make any change, nevertheless.
Can you please check and correct this issue in some priority? For us, RTS_CONTROL_TOGGLE is the feature of interest. Currently, we are not interested in other flow control modes.
Thanks in advance.