On Tue, 05 Nov 2019 08:18:42 -0500, legg wrote:

I've got a battery management unit that is reluctant to
demonstrate functionality. The vendor's terminal com
software seems non-functional (will not install).

So far the only evidence of life is a control line (one
of three) hard on, and rare /XFFE /FFF signalled outputs
on the rs232 port. Internal DC-DC fails to power LEM
sensor. Balancing terminals seem inactive.

Can anyone recommend a tutorial on poking a serial port
for status / data register contents ?

snip

Just had J1939 dumped in my lap. Without the vendors
com software, I'm afraid this is beyond poking.

RL