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Help unbrick my A1200?

Posted: Wed May 13, 2020 10:54 am
by Mixel
This is probably 99% user error.

First I’ll explain the state my Amiga is in..
I have 3.1.4 roms, it’s an A1200 with a IDE cf adapter for the hdd, and a PCMCIA - cf adapter for file transfers to/from my pc.. with an 8mb modern ram expansion. When I turn It on it waits for ages.. a minute or so, with a black screen before the kickstart screen appears - if the RAM expansion card isn’t inserted. If the card is inserted it doesn’t get that far, it’s just a black screen with a power light.

If the main CF (partitioned as dh0: and dh1:) is connected, it just does solid hdd light and never* boots. I can get half booted by messing about with floppies, but dh0: never mounts, just my dh1.

* I guess maybe it boots if I leave it doing it for an hour or something, I’m too chicken to try.

What did I do immediately before this? I made a copy of the 3.1.4 Workbench disk and changed its Startup Sequence slightly so instead of loadWB it ran xbench.. the idea was if I put the floppy in, xbench loaded, if I didn’t, workbench loaded. I wondered at first if maybe I messed up my WB install but now I think it’s hardware..

Even if I unplug everything, from the ide/cf card and revert to my old 3.1 kickstart roms, it’s still taking ages to show boot stuff. Currently I can’t get it to even the “hold both mouse buttons” menu when the RAM card is inside. :( I hope I haven’t damaged that, or the 1200’s motherboard. Without the card I can get the boot menu but I have to hold the buttons for ages as it’s hard to predict when it’ll appear.

Could the power supply be dying? I could have sworn it was recently a lot louder (Coil whine?) and now it’s silent.

The a1200 isn’t recapped.. I wonder if the power conked out while it was writing to the CFs.. I’ll make a full backup of the drives in UAE at least but what a downer. 😭

Ed:

Oh boy.. I thought I’d check inside the PSU and there’s no obvious big sign of mess other than see-through what looks like puddle stains..? I was very careful not to mess anything up inside it.. and put it back together.. plugged it in again and the Amiga doesn’t even output any video signal at all anymore.. so I definitely need a new PSU before I do anything else. 😅 it does seem that literally every thing I do at the moment makes it worse so it’s probably for the best I’ve hit a wall, d’oh..

Could this all have been caused by a rapidly dying PSU? Why would a wonky psu make loading kickstart excruciatingly slow? Oh well.

☹️

Re: Help unbrick my A1200?

Posted: Wed May 13, 2020 6:33 pm
by obitus1990
The delayed boot was probably something wrong with your boot partition. How big is the CF card? The larger the partition, the longer it will take to validate the disk and mount it. Also, is your RAM expansion PCMCIA friendly? Some 8MB (maxed out) RAM expansions will cause an issue with the PCMCIA port when you try to use them both together -- the PCMCIA port stops working. Try (if your expansion has them) to change jumpers on your 8mb card and have it only use 4mb and to see if the issue resolves itself.

Also, look at the RAM expansion and make sure it contacts the card edge of the motherboard completely. IF you've pushed it all the way onto the edge connector, pull it out slightly, by say, 1mm, then power on and see what happens. It may be poor contact. If no change, power down and check the card-edge connector of the RAM expansion. Make sure you haven't accidentally bent any of the legs that lead to the pins in the connector, as they are very thin. They are 90 degree pins that are soldered into the card itself and then run to the "teeth" of the connector. The 90 degree pins can be bent accidentally, causing them to contact each other and cause a short.

Re: Help unbrick my A1200?

Posted: Thu May 14, 2020 4:25 am
by Mixel
Thanks. 🙂

The delayed kickstart screen is/was happening when neither the cf card or ram card are installed.. and it happens whether I use the OG 3.1 roms or the new 3.1.4 roms.. it’s seriously weird.

I’ve copied the content of dh0 and 1 to a backup in Winuae, weirdly I had to use disksalv to see the files on dh0, they were invisible to workbench.. so.. god knows what happened there. I’m inclined to freshly repartition and prep the card again and copy everything back over and see if it at least boots in Winuae.

I hope I’ve not damaged the ram card.. ☹️

Now it’s out of action until a new PSU arrives (at least) maybe this is a good time to remove all the shielding and have a good look at the motherboard. I guess I’d need all that off if/when I send it off to be recapped anyway.

Re: Help unbrick my A1200?

Posted: Tue May 19, 2020 8:39 pm
by Mixel
I should follow this up to say it’s back up and running.. a new psu got it operating again, it’s booting at the correct speed, I restored the data from dh0:, it’s outputting a video signal, crisis averted.

I’ll still get it recapped at some point but right now I’m just glad it’s working again. I took off the top shielding and see absolutely no sign of leakage or problems. :D