Urgent 1541 help needed :(

Sam

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:help::bowdown:

I was transferring some data to/from my 1541, when I inadvertantly connected the xe-1541 cable while the drive was still on... it started rotating, and now it doesn't respond anymore to commands... not even from the c64... It just listen to "cbmctrl reset" from the dos window... what can I do??? I fear I have broken it.... ;( cry cry

Can anybody suggest anything to do, or what to look at?
Fuses? what else?

Thanks in advance
Sam

PS
With 'urgent' I mean, I'm leaving in some days, so if you have any idea I will try to fix it while I'm here... then I'll have to try again in two months...

---------- Post added at 14:07 ---------- Previous post was at 13:53 ----------

From R. Carlsen repair guide:

http://personalpages.tds.net/~rcarlsen/cbm/1541chip.txt

1541 CHIPS VS SYMPTOMS
PCB# 1540050 (early version) with ALPS drive mechanism (1982)

UC3 6522 VIA (SERIAL INTERFACE)
Drive powers up and resets normally. When LOAD attempted, screen
indicates "SEARCHING FOR ...", but no motors run and red LED does not
light.


What does that mean? Burnt out chip? Which one?

It all happened while the serial cable was connected so maybe this is the culprit, and the description of the symptoms is exact...

Can it be repaired?

---------- Post added at 14:14 ---------- Previous post was at 14:07 ----------

Other possible cause for a different version of the drive (I don't know where to check which one is mine... it's the first 1541 model without the knob, it has a thing to push down after the floppy is inside)...

1541 CHIPS VS SYMPTOMS PCB# 251830 or 251777 with Newtronics drive
mechanism (1984)


UB1 7406 (M53206P or 7707) LOGIC
Partial failure common cause of "SEARCHING FOR" (check also UC3)
and "DEVICE NOT PRESENT" errors. Total failure: drive powers up OK,
but does not respond to computer... no reset or disk access.

---------- Post added at 14:55 ---------- Previous post was at 14:14 ----------

There are two 6522 chips on the drive. So I swapped them and I obtained the correct symptoms according to the repair guide (uc4 failure), which are:

- red light on
- drive spinning (only if I remove the chip, anyway...)

If I just keep the supposedly broken chip in, the light stays on but it doesn't rotate.

If you agree with me that the 6522 and nothing else is the culprit, I'll start searching for a replacement one.

Let me know!
Sam
 
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Buzzfuzz

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Usally U1A and U1B, 74LSxxx and 74xxxxx, are dead, unsolder them, solder sockets into it and put in new ones.
 

Sam

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Dead diodes?

Dead diodes?

Thanks for your reply, I ordered a replacement 6522 and if it will not work I will definitely try to replace those chips too (or find another drive, since I'm not a soldering expert).

Since I wanted to get something out of my tapes I tried to emulate the missing 1541 by using vc1541 and 64hdd emulators.

Both didn't work. The cable test program shows the cable is connected and recognized, but the first software misbehaves when I type LOAD"$",8 and the second beeps when starting the connection, stating that there have been unrecognized commands. In the meanwhile, the commodore says DEVICE NOT FOUND.

So I think I blew up the xe-1541 cable too. As I said, I'm no expert, but I suppose a high current capable of blowing up an integrated circuit could also blow those 4 diodes inside the cable. Am I right? Is that possible?
 

Sam

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Still dead

Still dead

Hallo, today the replacement 6522 arrived, but it didn't work so I think there is something else broken. I hope I'll be able to fix it, and will search for the other IC mentioned here. Tomorrow I leave so I'll do it in December!
 

Buzzfuzz

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Thanks for your reply, I ordered a replacement 6522 and if it will not work I will definitely try to replace those chips too (or find another drive, since I'm not a soldering expert).

So I think I blew up the xe-1541 cable too. As I said, I'm no expert, but I suppose a high current capable of blowing up an integrated circuit could also blow those 4 diodes inside the cable. Am I right? Is that possible?

Ok, try to go to an expert and have him doing it, or someone here on Amibay.
No the 4 diodes will have survived it, the voltages and currents aren't high enough to blow these.
If they did, then they are really weak or damaged by a much higher current / voltage.
Even the parallel port of a PC side doesn't have that current / voltage to blow them.

And you can always order a new one @ amigakit.com, they have them in stock for around 14 euro's.
 

Sam

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thanks

thanks

well thanks again for your kind advice! I'll investigate further when I'm back... and will let you know! (y)
 
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