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6 years ago.
Cant read serial port
Hello,
I use the following code to read the outputs from a mbus converter. It is attached to a mbus master, that check for its slaves by sending a fixed fattern. The mbus levels are converted to 3.3 V logic, are observed on an oscilloscope and seem correct.
I have connected the output to PD_6 as a DigitalIn and let the input drive a led on the board. The led blink as expected.
The same output is connected to PC_10/PC_11 as a serial port. The output is measured by oscilloscope: levels seem fine. The led still blinks as expected. But, no output may be read from the serial port.
1 Answer
6 years ago.
Hello Per,
- Have you configured also the serial terminal monitor (running on your PC) to
8-bits, even-parity, 1-stop bit? If no then I would suggest to removepc.format(8, SerialBase::Even, 1);from your code. pc.printf("%s", data)requiresdatato be a C-style string (aka null terminated char array). Make sure thatdatahas enough room for the null char which has to be appended (unless the modbus message already contains such).
...
while (mbusSerial.readable())
{
data[i++] = mbusSerial.getc();
}
if (i > 0)
{
data[i] = '\0'; // terminate the char array with null char (to become a C-style string)
pc.printf("%s\r\n", data);
}
...
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