[Misc] GR3750 using SC7700

[PositiveBuddy]

I had a old GR3770 machine that had an external Controller. An SC7700.
The machine was damaged and disposed of. But before juncking the machine I salvage the SC7700 and parts needed for a future machine. These parts worked fine. I recently acquired a GR3750. Not exactly what I had, but I thought close enough. My salvaged parts from the 3770 fit fine and I adjusted the settings the SC7700 external card showed I had to do. But when I start everything up, the SC7700 has the blinking light that says no communication is possible with the Riso?
Does anybody know if I need to flip any of the dip switches or have any idea why this is happening?
Thanks

[M Rezac]

I have a similar issue going on with a used SC7700 and GR3750 I recently purchased. I believe the issue with mine is that the System ROM on the GR370 is not compatible with the SC7700. Not sure if this is the issue with your machine or not. If you start the GR3750 in test mode it will tell you what version your System ROM and Panel ROM are. I have two PDFs with the compatibility charts if you need them.

[PositiveBuddy]

I think I have the same PDF's you are talking about. What I have says I need ROM version 5 or higher, and I have 5.02. So I don't know if this is my problem or not.

[M Rezac]

You actually need one of the following:

S77 (V5.02A) part # 888-75502-000
S77 (V6.01C) part # 888-77601-000
S77 (V6.02C) part # 888-77602-000
S77 (V7.00C) part # 888-77700-000
S77 (V7.02C) part # 888-77702-000
S77 (V7.03C) part # 888-77703-000

I had 5.02 as well, but you need at least 5.02A.

[PositiveBuddy]

Any idea where i can get one of these EPROM?