I've used a DB breakout board connected to a usb serial came and just tapped the RX or TX pin one at a time. Works well.
I also should mention that I had an issue with a level shifter before where I hooked it up backward (TX to RX) and the resulting waveforms that came out the input (which was hooked to the device input) could sometimes be read by the device and sometimes not. I really can't recommend having an oscilloscope highly enough. Even a cheap analog one works. On Dec 1, 2017 8:05 PM, "John R. Hogerhuis" <[email protected]> wrote: > If you’re doing any serial programming whatsoever I highly recommend > having a sniffer of some sort. > > A Linux pc or raspi with two usb serial ports will do as a “man in the > middle” sniffer. > > — John. >
