Using RH controller VCUs

Actually I don't know how to run them alone I didn't try that yet by myself but I saw some Spanish guy retrofit his S-700 to Mach3 and AFAIK he succeeded. Which one of ServoAmps do you have in there? I think you'll need six fast PWMs for each axis (total of 36 PWMs), some kind of decoder for APCs and some glue logic around.

I don't have particular maintenance and troubleshooting manual for P-150 but for the first impression yours VCUs looks like very simmilar to the one I have (S-700 Arm with R-H). When I stated that you'll need 36 PWMs total I thinked about bypassing PWM signals that is originally provided by Auxis Control Board which AFAIK is some kind of DSP. Because it is two axis VCUs there are two 20pin connectors signed as CN1L and CN1M. One for each axis with following layout:

1,3,5 ... PWMA - PWMC (in) multiplexed with ALM1,ALM2,ALM4 (out) ... PWMs (in) and Alarm code (out)
2,4,6 ... COMA - COMC ... PWM commons
7 ... DRDY ... Servo amp. ready
8 ... IR ... Phase-R current
9 ... GDR ... Phase-R current
10 ... IS ... Phase-S current
11 ... GDS ... Phase-S current
12 ... MCON ... MCC control
13 ... GND ... Ground
14,16,18 ... PWMD - PWMF (in), PWMD multiplexed with ALM8 (out)
15,17,19 ... COMD - COMF
20 ... NC

I'm pretty sure you'll find necessary information about signal description and connections in this manual: https://www.ebay.com/itm/Fanuc-Robo…l-/382000943655