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A10001986
1986

Posted Thu Aug 09, 2018 2:01 am

Your config does not match the description I quoted. So what happens if you swap the drives on the cable (df0 last, df1 first)?

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Zippy Zapp
CA, USA

Posted Thu Aug 09, 2018 7:47 am

A10001986 wrote:Your config does not match the description I quoted. So what happens if you swap the drives on the cable (df0 last, df1 first)?
It doesn't work right. It sees DF1: as DF0: and any disk inserted into what is supposed to be DF0: just says ???. Plus the drive light stays on all the time with DF1: Also in the early startup menu it shows only DF0: and does not show a second drive.

I have not found my instruction sheet yet that Commodore sent with the second drive but I am pretty sure the instructions on the internet that I have found about the twist going to DF0: are wrong. I opened my other single drive A2000 and the twist part of the cable is coiled over the ribbon from the factory. The untwisted part is plugged into DF0:. I am going to try swapping cables and see if that changes anything. If not I wont worry about it because it seems to work fine.

User avatar
femuruy

Posted Thu Aug 09, 2018 8:28 am

Maybe it is just a problem with the FDD board that leaves the light on? Chinons need to be recapped too!

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A10001986
1986

Posted Thu Aug 09, 2018 10:20 pm

Never heard of Chinons needing to be recapped. (Exception FB357A, there is a traditionally leaking smd cap near the motor. But here we are dealing with FB 354s.)

Wires 4 and 6 are exactly the LED control (INUSE), that's why swapping drives should work regardless, except for erratic LED behavior. LED always on more sounds like the cable plugged in the wrong way, one pin off or the like.


User avatar
A10001986
1986

Posted Fri Aug 10, 2018 9:04 am

Yes, thanks, I know it CAN be recapped, but like the A2000 or A3000, this is really, really seldomly really required.

I am sure that this case is not cap-related, because the drives actually work, and the relatively big caps only are there to stabilize power from the power source or for the motor.

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Zippy Zapp
CA, USA

Posted Fri Aug 10, 2018 11:07 pm

I don't think it is a cap problem either as I had the drives apart to lubricate the mechanisms and the cap *looks* fine, no evidence of leaking.

I have heard it said that the caps in the A500/2000 and really the 64 and 128 too, could last 40 years or more. Well some of them have been lasting 30+ years so I am not so sure they are wrong.

I still have yet to swap out the cable or the drives with the other A2000.

Meanwhile in the restore process I found an A2091 SCSI card locally. It came out of an A2000 that was working but sold off for parts. No RAM installed. I popped it in and it shows up in Sysinfo so I will need to hook up a HD to it to see if it works fully. It has ROM 6.6, which is one revision before the final of 7.0. I think I could probably burn a set of 7.0 ROMs as I am sure the .bin files for these are around.

I thought I had DRAM that could work with the board but apparently I am all out. I ordered some 44256 DRAMs. I had 30+ 41256 but those are wrong. Oh well.

I have a few SCSI drives to choose from so that should be ok. But I am considering getting a SCSI2SD for this one.

User avatar
Zippy Zapp
CA, USA

Posted Fri Aug 17, 2018 8:45 pm

Received the 44256 DRAM today. Will try installing that this weekend. I also received some 3.6v NiMh batteries intended for cordless phones. This is supposed to work and the Amiga will charge the battery. I was going to go with a CR2032 cell but I wanted to stick with rechargeable. I installed single pin headers for + and - and will solder connector wires to the battery. Then it just needs to be plugged in and velcroed or double-sided taped to something away from the motherboard.

Pulled out a Quantam Fireball 1080 that I had previously used with a Mac many, many years ago. It is 1GB and I was able to plug it in to the A2091 partition and format it with no problems. Did a clean install of 2.1 and everything seems nice. I also received a couple of SCSI2SD devices too just to test out. A V5 and a V5.1.

A2000 Screws
I lost all the screws that screw into the power supply and a few that screw into the motherboard. I was able to find replacements for the PSU and the case so I bought some new Stainless steel ones to replace the old corroded ones that seem to be the norm for the 2000.
Sizes:

Case and the PSU are metric: M4 x 6mm, .70 pitch thread.
motherboard screws are metric: M3 x 6mm, .50 pitch thread.
They are available at most hardware stores. I couldn't find a replacement for the screws that hold the cards down. They are not the same as PC screws that I can see. The threads are finer on the Amiga.

Still need to test out the floppy cable or drive on the other 2000.
I think I want to install a kickstart switcher on this A2000 and add 1.3. I know I can use Relokick but I don't know.

I love restoring these computers and getting them to work the way they should, it is oddly rewarding.

EDIT: RTC Battery installed. The original battery is 80mAh and lasts about 5 months of battery backup when fully charged. The new one is 800mAh which should last years of backup when fully charged. The thing is I don't think the Amiga's low power charging circuit can charge it very quickly. I read that the original battery took about 15 hours to fully charge. So this new larger capacity should take days to fully charge. Ah well not a big deal. It is doing what it should.

User avatar
TjLaZer
Tacompton

Posted Mon Sep 24, 2018 1:32 pm

Swap the cables from what you showed in the pics. And did you jumper J301? Should work.

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Zippy Zapp
CA, USA

Posted Mon Sep 24, 2018 3:18 pm

TjLaZer wrote:Swap the cables from what you showed in the pics. And did you jumper J301? Should work.
It works fine It's just that both LEDs light up when either drive is being accessed. Odd but still works fine.

I have confirmed cables and jumpers are all correct.

However I am going to try a different cable or redo a PC cable just in case I hosed this one when I tried to fix what turned out to be a key pin. There is a PIN missing on many B2000 motherboards and it is intended to be a key pin. To prevent you from plugging the cable in the wrong way they installed a pin inside the cable. So the first time you remove the cable and notice there is a pin missing and you happen to look at the cable and see the pin is "stuck" in the cable.

This happened in 1988 and caused a panic among some A2000 users and service centers then. In the PC world they filled in the hole of the corresponding connector so you knew it was keyed. But Commodore decided to use an actual PIN so that it looks like you broke the floppy Header. It fooled me and on this cable, like an idiot, I took it apart and removed the pin for fear it should come loose and short something out. Perhaps I caused a wire to short in the cable. I will check.





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