My experience with
MPHL Running
This winter the further the temperature in my workshop fell, the more persistent the following problems emerged:
When the main switch was turned on, the message "MPHL RUNNING" appeared
The machine no longer responds to any keystrokes
Switching off the control does not change either.
Rather, the NSV gets stuck on the error message "F.2".
Even multiple RESET on the NPC does not change anything.
At the same time, the “ERRROR” diode on the NPP came up.
Also in combination with the "NOT READY" diode of the NPC with simultaneous NSV display "1.7" or "1.2"
The control can be started up to a limited extent in the NSV switch position KD, but does not react to any inputs there either.
A CMOS error message also came up during one of the start-up attempts
CMOS CHECKSUM0085329A
Remedy:
Due to a similar error description in this thread, remedial action was first attempted by heating inside the control cabinet. (Workshop temperature winter approx. 14 ° C)
This brought an improvement for a few days. In the end, the error occurred again frequently.
During operation, the control indicated block processing, but no longer responded to any key input. When the control was switched off, a falling relay could also be heard, so that the drive had failed completely, as if the drive had been switched off.
By replacing the NPP card, with a spare the machine works properly.
My idea was that one of the GAL / PAL components of the NPP is probably defective.
It could not be one of the EPROMS because the checksum test does not give any error messages after starting the machine.
All PAL / GAL ICs of the defective card were checked with a programming device and two unreadable ICs were identified.
Lattice GAL 16V8 Nr.
44209-640-41
Lattice GAL 20V8A Nr.
44209-640-51
After exchanging the two ICs, the replacement card was replaced by the repaired card and the machine starts up again perfectly and moves to the reference points.
Yeaa...
After approx. 3 days, the (workshop) fuse failed (happens sometimes) when the machine was switched on. By inserting the fuse, the machine could be started, but shortly after the start-up it again showed "
MPHL RUNNING"
A reset on the NPC gave the machine a normal start.
During operation, the controller briefly got stuck when characters were searched for or exchanged in an extensive program (approx. 12000 lines) with the editor. It appeared that the controls had problems with that. When trying to stop the edit process, the control came up with the following image, whereby the control no longer reacted to any key input:
Error
2302 "emergency shutdown"
Restarting the control did not cause any further problems.
After about 3 weeks, with the machine barely starting up in the meantime, the error message
MPHL RUNNING appears again.
Replacing the repaired NPP card with the replacement card eliminates the error.
The PAL / GAL ICs of the defective card were checked again and for this time two other unreadable ICs were identified:
GAL 16V8 Nr.
44209-640-61
GAL 16V8 Nr.
44209-640-81
After exchanging the two ICs, the replacement card again was replaced by the repaired card. But but this time a clean start was not possible.
The situation now is that the NSV shows an F.2 and the NPP shows the ERROR LED all the time.
So it looks like that there is another component on the NPP defective. A visual inspection gives no indication.
Now I'm finished with my Latin.
The machine now runs normally with the replacement card. Perhaps one of you has an idea what to check next at the NPP…?