[offroadxx]

I HAVE A MIYANO TSV-21 VMC WITH AN OM-A CONTROL AND WAS WORKING GREAT, SHUT IT OFF CAME BACK TODAY AND WHEN POWERED UP, THE SCREEN SAYS #998 ROM PARITY ERROR. IT WILL NOT LET ME DO ANYTHING WITH ANY KEYS AT ALL. I AM STUCK AND DON'T KNOW WHAT TO DO. ANY HELP WOULD BE GREATLY APPRECIATED!! THANK YOU

[dcoupar]

Sounds like one of the ROM's is bad, or the entire board. Might be time to call for help?

[offroadxx]

What exactly is the ROM, I will check and see what the number is on the screen,I did notice that there is a red light on in the cabinet with an SO next to it, then below that is an S1, below that is WDA which those two lights are green. Who should I call, Fanuc or Miyano. Thanks again.

[offroadxx]

The error reads

998 ROM Parity: ROM NO. 0412-08
OC1
OC2

[fanuservicetech]

Even though it says ROM parity error, it appears to me you may have corrupt RAM memory on the control. It is highly unlikely to have 2 ROM chips go bad at the same time. Basically alarm is indicating that ROMs in location OC1 and OC2 are bad. Please take a look at the ROM chips (usually about 0.5 inch x 1.5 to 2.0 inch). Fanuc software ROMs will have lable "0142" on them. But I think the OC1 and OC2 location is for PMC ladder ROM chip. I am leaning towards corrupt. In that case you will have to clear memory by powering on while holding "RESET" & "DELETE" keys. Doing so will ofcourse clear all memory on the control. If you have local CNC tech or close to a Fanuc branch, might be a good to call for service. No easy way out on this one.

[offroadxx]

Hi fanuservicetech,
I appreciate the info. You are thinking corrupt, if I clear all memory and parameters and do a reload do you think this might clear it up, or possibly a good chance? I have no problem doing this at all as I just added an extra 120 meters of memory to it about 2 months ago. I have all parameters & diagnostics backed up on the computer to reload. Thank you

[fanuservicetech]

Yes. If you have the data backup and you are familiar with the procedure on how to restore, please try clearing memory (reset+delete while power on). If can get rid of alarm 998 by doing so, it is a good sign but you are not completely out of the woods yet. Type in all you 900 series (option parameters) and power off back on. If no more 998 alarm after that, then you are in good shape, it is just a case of memory corrupt. You just have to restore the rest of the parameters (including PMC/Diagnostics).
Before you do any of that, please check your memory backup batteries (1.5V D cells x 3) and replace them if necessary.

[spark-el]

I am assuming you have powered the machine off at the main electrical disconnect and waited for at least 30 seconds? If not, try that and make sure all boards are seated well, and that your eproms at oc1 and oc2 are seated ok, and none of the legs are broken. Incidentally, reset-delete clears cnc memory only, the ladder doesn't go anywhere. If those chips are bad (which is very rare), you have to burn the ladder on to these chips with a eprom burner.

[offroadxx]

Thank You for the reply, I will try to reset parameters and do a reload. I will load 900's first, then set my baud & speed, parity then dump them in from pc. I have to hand input the diag's for some reason it won't let me put them in from the pc. I will try this first and see what happens with it. Thanks again.

[rojevavi]

Hi,

I have a fanuc otb control and i had reset the memory but after i done this, the control always start in edit mode, i try several things but always start in edit. I loaded several times the parameters and diags. before but in C and D version not in B. I ussually out in MDI mode then power on the control and the control will be in MDI mode, but in this case nothing. Somebody knows what happend?

Thanks