M4 board fried my cpc?

[rntr]

Hi,

I've been using my 6128 with the M4 board for a few days. Everything perfect. No issues. Yesterday, I removed the board to re-insert the microSD. I connected it back on the cpc, turned it on... kaput... I removed the board and still nothing. Since then, the cpc is not starting. I get a corrupted startup screen that gets more and more corrupted until it hangs completely.

Any ideas? Did the M4 fry my cpc?!! Can I fix it?

Thanks,
JB

[eto]

It's unlikely that the M4 fried the CPC but of course a short could harm e.g. the ROM. 

How is the M4 connected? With an MX4 board?

Can you share pictures of the corrupted start-up screen and the hardware set-up? That might help to identify the issue. 

[rntr]

The M4 board was connected directly to the expansion port. It starts-up in blue a bit corrupted, and keeps on twitching fast until it ends like the second picture or completly blue or with the text moving to the right. See the pictures. You cannot press a key or do anything.

The hardware setup is a 6128 connected to a color monitor. Or to a green monitor. Tried both. Same result.

https://imgur.com/a/qNhrgXE

[Duke]

Most likely just the mainboard rom is failing and no the M4 doesn't fry CPC's

Probably it would be a good idea to prepare the M4 board with Noel's diagnostic rom https://github.com/llopis/amstrad-diagnostics

And have a run, if the upper or lower rom of the Amstrad mainboard is failing, you can bring it back alive by uploading those roms to the M4 board.

[rntr]

Hi Duke. Thank you for replying.

This is what I did:
- Tried lower and upper diagnostics roms : nothing, blank screen
- Removed them and put basic1.1 on port 0 and 6128 english rom on port 31: nothing, blank screen
- Removed the M4 board... and now the cpc boots up properly!! that's a relief!!
- However, now the M4 does not work. I've tried multiple roms and nothing, blank screen. 
- The M4 seems to be working (see picture of my current rom setup) because I connect via web, but on the cpc: blank screen, no color, no letters nothing.

Any ideas on how to make the M4 work now? Also, any ideas on what may have happened? 

Thanks!


https://imgur.com/a/79qYcDi

[Duke]

Hi Duke. Thank you for replying.

This is what I did:
- Tried lower and upper diagnostics roms : nothing, blank screen
- Removed them and put basic1.1 on port 0 and 6128 english rom on port 31: nothing, blank screen
- Removed the M4 board... and now the cpc boots up properly!! that's a relief!!
- However, now the M4 does not work. I've tried multiple roms and nothing, blank screen.
- The M4 seems to be working (see picture of my current rom setup) because I connect via web, but on the cpc: blank screen, no color, no letters nothing.

Any ideas on how to make the M4 work now? Also, any ideas on what may have happened?

Thanks!


https://imgur.com/a/79qYcDi

Try to see if the M4 works without the microSD card inserted.

[ajcasado]

Could it be possible that the M4 SD card filesystem is corrupted?

[rntr]

If I remove the microSD and insert the M4 same result: blank screen.

If I put the microSD back in I can access the M4 board via web again. Still blank screen. Doesn't look like the card is corrupted.

[VincentGR]

Once a friend had a similar problem.
What I did was to turn on the machine without the SD and insert it later with the latest firmware update on the card.
A power cycle did the job.

[rntr]

Tried what VincentGR suggests. No luck.

Deleted everything from the M4 card. Copied the latest firmware bins following the docs. The firmware was already v2.0.7 but still, it made the update, created the M4 folder and report.txt. Nothing. Blank screen still.

I copied my ini file and still can access the M4 board via web, and still blank screen on the cpc. sigh...

[ajcasado]

Have you cleaned the expansion port contacts?,  they get rusty with the age causing high voltage drops in the expansion lines.
The 5V voltage level can be a source of problems, if you have a voltage meter test it.
Are you powering the M4 with an external 5V power source via the micro usb connector? If the answer is yes try a different 5V power source, if not try to use an external 5V power source.

[genesis8]

If I put the microSD back in I can access the M4 board via web again. Still blank screen. Doesn't look like the card is corrupted.

;
Do you mean that in windows you did right click on the drive letter of the SD card, Properties, utilities (not sure of english translation in windows) and ask for a scandisk ?

In command line as administrator you can do a chkdsk driver letter: /f

[rntr]

Have you cleaned the expansion port contacts?,  they get rusty with the age causing high voltage drops in the expansion lines.
The 5V voltage level can be a source of problems, if you have a voltage meter test it.
Are you powering the M4 with an external 5V power source via the micro usb connector? If the answer is yes try a different 5V power source, if not try to use an external 5V power source.

This same setup was working fine a couple of days ago. Without a glitch. Consistently. 

The expansion port is clean but I cleaned it up again today just in case with a bit of alcohol. In my experience, when something is wrong with the expansion port at least there's something on screen, you can at least see the BASIC screen, you can even type something before it glitches out. But I get nothing, no glitches, no text. Blank, like when the power is off. And, as I said, if I remove the M4 the machine works now.

BTW I tried using a different USB power source (5V). Same result. 

Checked the microSD card for errors. It's fine.

[Duke]

Send me a pm, if you want to arrange for me to fix/replace it.

[rntr]

I'll send the board to Duke and he'll try to get it fixed or check what's wrong. So thanks to him for having the patience and time for this.

And thank you all who sent messages trying to help! Appreciated!