KoltonS

Noise on the 5V line ended up being the culprit. Still some sort of issue when using non-inverting logic but once we switched back things have stablized. Could you provide the mfg PN for the 100pin on the C100FF-X cable? And if you know of anyone making the same cable, could you provide that info as well?

Fausto, I want to give you an update that we are still looking for a root cause for this issue. Nothing to report yet. Hopefully tomorrow I get some time and then I'll answer everything and provided whatever other details shake out. As for the cable if Digilent is no longer supporting them is there another place we can source these or are we going to have to build our own now? Thanks!

I am working with a PCIe-DIO96H and two SSR-RACK48s, one for inputs and one for outputs and having issues with the inputs "flickering" on and off. The PCIe-DIO96H is installed in the PC and the two SSR-RACK48s are installed in an electrical enclosure. They are connected using the MMC cable (I do not recall the exact PN but I believe it is the 1M length). The LED indicators on the inputs "SSRs" are not illuminating as if they are being triggered but the PCIe-DIO96H is registering that random inputs go high for ~<1s before returning to the expected state. There are no high current lines running near the ribbon cables, the two PSUs are GND referenced, all the parts were direct from MMC. Where is the break down between these two devices? I noticed a similar issue with the output board during PC power on since the PCIe-DIO96H defaults all ports to inputs aka high impedance. It seems as though the pull-up (configured through InstaCal) is either insufficient or we just have huge amounts on noise on these ribbons. Has anyone else ever integrated these two devices? Is there a system integrator out there that may be able to shine some light on what is going on? I'm feeling at a loss with this IO setup. It's all within the same ecosystem and being used in a normal configuration and still not working as intended.

EDIT: Double post. Site froze up.

Thanks for the info @Fausto We have swapped the chips for non-inverting as you mentioned but now, I am wondering if I should swap back and just invert the software controls since it seems the pull-down option is unable to keep the SSR-RACK in a clear "off" state on power up, but the pull-up option seems to create the expected output. As for powering the SSR-RACK (5v only) via a relay that is certainly an option. One last question, I see a lot of the MMC parts have been marked legacy and kind of buried on the Digilent website, are the SSR-RACK48 or the PCIe-DIO96H going end of life anytime soon? Thanks!

Yesterday evening I tried installing the bodge wire just to see if that would improve the situation and realized I seem to have a bigger problem. Even with the two being powered together I am getting erroneous outputs coming on before our software starts. From what I understand this is because the 82C55 emulation via the PCIe-DIO96H defaults all ports to inputs after a reset and the pull-down resistors (configured via InstalCal) should prevent the high impedance inputs from floating high and turning on relays on the SSR-RACK. When I change the configuration of the resistors to pull-up all the outputs on the SSR-RACK turn on as expected. But when configured for pull-down the erroneous outputs come back again. Any ideas?

I have an SSR-RACK48 populated with output relays being controlled by an PCIeDIO96H and am running into an issue. The PCIeDIO96H is powered the computer PSU and the SSR-RACK48 is powered by a separated PSU in the electrical enclosure it is mounted in. The two GNDs from the separate PSUs are referenced. The problem I am having is that the pullup/down configurable resistor in the PCIeDIO96 is not active unless the board is powered (aka the PC is on). In my current setup it is possible for the PC to be off but the electrical enclosure to be on. I would expect that all the outputs would default to the off state but instead without the pullup/down enabled I see random outputs turn on which is not desirable behavior. I am looking for a solution that avoids this situation. Currently I see a few options. One would be to run 5v from the PC PSU to the system electrical enclosure and use that to control a relay and in turn control the power to the SSR-RACK48. Second is there is 5V on the ribbon cable from the PCIeDIO96H but it's a N/C on the SSR-RACK. A bodge wire from the N/C line to the 5v input on the SSR-RACK48 would provide power but I am not sure is this was not done in the design intentionally. Third option??? I am not sure, neither of the options I have proposed feel like the intended answer. Have I overlooked something or are these boards really just meant to both be powered off the PC or this odd behavior ensues? Any feedback/input would be greatly appreciated. Thank you!