AttributeError: 'UART' object has no attribute 'wait_tx_done'

[untitledlt]

Looks like micropython UART does not have wait_tx_done but it's used in https://github.com/techbase123/micropython-modbus/blob/master/uModBusSerial.py#L98

[ThomasRgbg]

I'm trying to do this instead with some timing calculations. See https://github.com/ThomasRgbg/esp8266-pichler/blob/83379d6ef57f6f5afdd2535a2cbf9ca922b5c4ae/uModBusSerial.py#L106
Maybe not most elegant and might need a bit of calibration with the scope. But at least works for my Modbus RTU devices.