[david_chen]

Hi All,
I just bought a used milling machine with Fanuc OMA (digital servo),every thing appears good working except the ATC but I cannot fix the problem... because the ladder diagram cannot display on CRT and the machine come without any documents.
On the PMC-M card ,I saw 2 roms labelled O11 & O12 and they are 27256 ,I wonder if they are correct? because I have told that the roms O11&O12 on OMA are 2764
One question : are that roms 27256 correct?
Can experts on the forum help me translate the 2 rom files to the readable ladder form? Any helps will highly appreciate
Thank you in advance,
David

[fordav11]

if the machine works and does anything the ladder is good. without the ladder the machine is just a boat anchor.
to check the ladder you would need to read the EPROMs and assemble the ladder into one file then use some software like Fanuc Ladder III to view it.
some models allow viewing the ladder on screen by changing a parameter but I think the Model A like yours does not have that capability.
If the ATC is not working you may have mechanical or electrical/switch fault. you don't really need to see the ladder to fix it.

[Shoprag]

The O-A&B controls will not display the ladder. Most of the machines used the 27C64 chips. I have seen several that used the 27C256 chips. You will need a Fanuc EPROM reader such as the PC-Writer or System P-G to read the chips. FAPT Ladder I or II will be needed to read the logic.

If the OEM is still in business ask them for a copy. If not, you may be able to locate someone with a machine that is close to this one.

[memoryman]

Maybe a (protected?) program/macro to do with the toolchanger is missing or not being called?