NI-x100 Serial Problems

sentry07

I've run into several systems where there's data corruption problems on the first few COM ports if you're controlling devices at 115,200. It's like the register doesn't update by the time the clock signal goes high again and the previous byte gets copied. So if the device sent:

$01,$02,$03,$04,$05,$06

I would get:

$01,$02,$02,$04,$05,$06

I was told (not by AMX) that the first few COM ports shared hardware resources with another part of the system (AXlink, I believe). I'm assuming that if something happens on the other part, the COM port loses its timeslice, which would cause the register not to update. Is this documented anywhere? If not does anyone have more information about it, like which ports on which masters, they'd be willing to share?

Thanks!
-Eric

RicardoSiqueira

I believe that the COM Port 1 shares resources with the AXLink bus on the NIs. Usually, I skip Port 1 on most projects or use it only with less demanding equipment control.