I've just tried the bit banged version of the RS232 component and the output on my terminal program (PuTTY) was garbled. Looking on the scope revealed that the bit time was only 89.5% of what it should be, i.e. the rate is high.
This behaviour was consistent for 9600 and 19200 baud rates.
Fooling the component by reducing the baud rates to 8592 and 17184 respectively using the custom baud rate setting solves the problem but I still need an acknowledgement that this is a bug or that I am doing something wrong.
tia
Brian.
Software RS232 Baud Rate Problem
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Brian Walsh
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Re: Software RS232 Baud Rate Problem
hello Brian,
We have tried to develop delay calculations for the software uart to cover a range of devices, baud rates, and clock frequencies. It appears that some combinations do not work as well as others.
The reference configuration is a PIC16F877 running at 19.6608MHz, communicating at 9600 baud
'Tweaking' the baud rate setting is a good way to apply correction to calculations that are inaccurate.
We will improve the calculations in future releases of Flowcode.
We have tried to develop delay calculations for the software uart to cover a range of devices, baud rates, and clock frequencies. It appears that some combinations do not work as well as others.
The reference configuration is a PIC16F877 running at 19.6608MHz, communicating at 9600 baud
'Tweaking' the baud rate setting is a good way to apply correction to calculations that are inaccurate.
We will improve the calculations in future releases of Flowcode.