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Products => Test Equipment => Topic started by: ddavidebor on June 29, 2013, 08:50:34 pm

Title: Where to find rom data for fluke combiscope?
Post by: ddavidebor on June 29, 2013, 08:50:34 pm
Hi, i've a fluke combiscope and it beeps continuously at power on.

I think i need to re-program the rom, but i'm unable to find it in internet.
Anyone knows wherto find it?
Title: Re: Where to find rom data for fluke combiscope?
Post by: free_electron on June 29, 2013, 09:12:46 pm
Which combiscope ? There's like 40 different ones...
Roms dom't go bad very often. Those machines use old fashioned eprom.

Id check for missing voltages first.
Get the service manual. The beeps may mean something...
Title: Where to find rom data for fluke combiscope?
Post by: ddavidebor on June 29, 2013, 09:29:27 pm
Power supply is ok, and service manual doesn't have a troubleshooting chart.

It power on but nthing happens. Light on, but nothing on screen.
Title: Re: Where to find rom data for fluke combiscope?
Post by: nctnico on June 30, 2013, 12:13:57 pm
I'd start checking whether the CPU runs and what the address lines do. Problems like these won't get solved by just swapping components blindly. In the end you can swap all the components without any luck because there is an open trace somewhere on the PCB. Another thing to try is reseating all the socketed devices (=lifting the chips a bit from their sockets and push them down again) .
Title: Re: Where to find rom data for fluke combiscope?
Post by: free_electron on June 30, 2013, 01:52:24 pm
indeed, socket parts sometimes give trouble.
Title: Where to find rom data for fluke combiscope?
Post by: ddavidebor on July 02, 2013, 05:39:22 am
Nope, nothing changed.

The cpu sure run, or the buzzer will not work.

Well, i will check the schematics but i'm pretty sure,



Title: Re: Where to find rom data for fluke combiscope?
Post by: duskglow on July 02, 2013, 05:50:45 am
Agree with free_electron.  I think if the ROM were bad it wouldn't be constantly beeping.  That's an error mode of some kind.
Title: Where to find rom data for fluke combiscope?
Post by: ddavidebor on July 03, 2013, 02:06:58 pm
It has two firmware one from a mask rom, one from an eprom.

The first with basic start up sequence, the second with operative system.
Title: Where to find rom data for fluke combiscope?
Post by: ddavidebor on July 03, 2013, 02:07:29 pm
Quote from: nctnico on June 30, 2013, 12:13:57 pm
I'd start checking whether the CPU runs and what the address lines do. Problems like these won't get solved by just swapping components blindly. In the end you can swap all the components without any luck because there is an open trace somewhere on the PCB. Another thing to try is reseating all the socketed devices (=lifting the chips a bit from their sockets and push them down again) .

What you mean by "what the address line do"?
Title: Re: Where to find rom data for fluke combiscope?
Post by: nctnico on July 03, 2013, 07:24:30 pm
See if they all toggle every now and then and have valid logic levels. An address line not toggling or having invalid logic levels is a tell tale sign there is a short or a chip is bad. The same goes for the data bus.
Title: Where to find rom data for fluke combiscope?
Post by: ddavidebor on July 04, 2013, 11:40:23 am
Ok thanks!