ex_usb_serial example help!!!!

martinisonline · Joined: 04 Feb 2006 Posts: 1

I try to build the ex_usb_serial example but it not works at all...

Lets say:

COM1: virtual com port created by the drivers (USB)
COM2: physical com port

In the COM1 --> COM2 direction everything works great
at COM2 --> COM1 direction nothing happens...

someone had the same problem???
Solutions??

Tanks in advance...

palermo · Guest

I had the same problem, i just changed

#use rs232(baud=19200, xmit=PIN_C6, rcv=PIN_C7)

to

#use rs232(baud=19200, xmit=PIN_C7, rcv=PIN_C6)

And now it worked.

Does anyone no the reason?

Thanks,
Bruno

PCM programmer · Joined: 06 Sep 2003 Posts: 21708

What you've done by switching the pins is to make a software UART.

A software UART can't lock up if the receiver is overrun, but the
hardware UART can.

You can test if this is the problem by putting the pins back to the
hardware UART configuration, and then adding the ERRORS parameter
to the #use rs232() statement. This will clear any overrun errors
that occur, and prevent the hardware UART from locking up.

Example: