[countryguy]

232 can get fussy - there are a number of testers both soft and hard ware provisioned.
Like:
https://www.stratusengineering.com/product/ez-tap/
https://dev.to/oscar37921395/top-5-s...rs-software-jk

I've seen so many different issues that it's hard to say w/o just trying a lot of elimination and substitution.
rs232 uses +12/-12 on the haas I believe. Power look ok? I know on my older haas, they '*derive' the -12V on the serial chip so it's hard to say on that (-) supply line. Mabe used, maybe not.
*This means w/ a few components and an IC, they make the -12Vdc used for 232 inside the chip more or less.

Anyway, try a 4ft cable. yeah.. I know, but unplug and haul the PC or lappy on out there and try it.
Take your original 20ft, Remove 4ft- Try the 20 while your PC is next to the Haas.
Try a different PC to send?
Knock the baud down to 4800, then 2400... any diff?
inspect inside the haas where the DB connector is. any goo and nastiness?

Just some basic thoughts I'd be checking/trying w/o too much fuss.

i haven't played with parity check but i will have a look.

i stick to 9600 baud on all machines since the length of the cables is roughly 20ft sometimes a bit longer.

thanks for the reply, appreciate it