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chuckcmagee
March 22nd, 2009, 12:03 AM
I have one of those dual 8050 floppy drives. I reseated lots of the chips but I still get red LED flashes over and over. I counted them. I get 4 short red flashes, with a green led when not red. A short pause and the 4 flashes goes again. The LED on the left drive flashes on and off along with the green/red middle one. The right drive LED stays a solid green all the time.

I am sure, like everyone else, that those 4 flashes mean something. Anyone have a clue?

MikeS
March 22nd, 2009, 12:13 AM
Hope someone else has an answer for you; the manual says four flashes have no meaning...

http://www.devili.iki.fi/Computers/Commodore/8050/Service_Manual/

Specifically:

http://www.devili.iki.fi/Computers/Commodore/8050/Service_Manual/page_5.html#Flash

cosam
March 22nd, 2009, 04:25 AM
I get 4 short red flashes, with a green led when not red. A short pause and the 4 flashes goes again. The LED on the left drive flashes on and off along with the green/red middle one.
Just so we're clear: it's 4x red, 1x green, pause, repeat - right? Assuming the list of flash codes is checked linearly, this would in any case suggest that everything up to and including 3 is OK, which narrows down your search a little.


The right drive LED stays a solid green all the time.
I didn't even know they were tristate LEDs - or do you mean it stays solid red? Either way, that doesn't sound right. Maybe disconnect the right hand drive and see if that changes anything?

chuckcmagee
March 22nd, 2009, 06:48 AM
Ok, I moved the 6502 microprocessors around (switched them). The flashes stopped. More testing in a bit. Now I have both drives green led and red led in the middle, but I haven't put the cable back on yet. That diagnostic page said if drives come on green and stay on, then that 6502 I was messing with is likely the fault. I stuck both of the 6502s, one at a time obviously, into an Apple IIe and they work fine. I put all the 6502 back where they started from. We will see if connecting the cable changes anything in a few. Letting my back recover some. Whoever said getting old is no picnic was sure right.

carlsson
March 22nd, 2009, 08:45 AM
Good luck. Trouble-shooting disk drives with little or no documentation is a difficult task even if you have a pile of spare parts of unknown condition to pick from. Besides I still think the 6502 CPUs are one of the toughest components in this era of electronics. Of all the bigger ICs involved in a computer or floppy drive, the 6502 seems the least common to go bad, although one would think otherwise since it is the brain of a system.

Druid6900
March 22nd, 2009, 07:47 PM
Could have just been dirt or corrosion in the sockets that was dislodged when you pulled them to switch them around.

Sockets have as many downsides as upsides.

chuckcmagee
March 22nd, 2009, 10:03 PM
Well, all the documentation says I should have a green led on in the middle and the 2 drive leds should be off. Not getting that at all. Hooking up the proper cable to a CBM 8032 has no effect on the led lights.

I have a green led on for each drive and the one in the middle is red. Of course, the " : " key doesn't work at all, making typing a string with a : in it very tough indeed. I suppose I need to remember that basic function that converts a decimal number into a character. Hmm, one would bet it is called char$ or maybe asc$.

From looking around, appears I will have to actually clean the keyboard myself. I keep seeing machines on ebay but they always have the phase "of course keyboard not working correctly." Seems it even repeats as I have read at least one where he cleaned it 3 or 4 years ago and it is back to screwed up again.

MikeS
March 22nd, 2009, 11:01 PM
That's what mine does: the drive LEDs both blink a couple of times and stay off, and the status LED alternates red/green/red/green and stays green. At least that's what the working one does; on the nasty one with the seized bearings etc. that I got from my pal in Hamilton (I'm not complaining Dru!) all LEDs come on red and stay that way.

CHR$(x), but I doubt that it'll help...

A bad keyboard just adds that certain little something to the troubleshooting process, doesn't it... a nice soothing project for a rainy day...

Good luck!

chuckcmagee
March 23rd, 2009, 12:24 AM
Yep, I did it. Was watching National Geographic and it hit me chr$. I even figured out the dec. value for : in my head because I remembered seeing "789:" frequently. 9 = 0x39 so : must be 0x3A which is 3X16+10 aka 58.

So, red/green/red/green you say. I get no changes in the lights at all now. Come on, stay on. Cable being hooked up to a live system has no effect either. Green on each side, red in the middle.

I only had to type ?chr$(58 ) about 9 times because make one mistake and I found the arrow keys don't work either. Sigh, time to get out the screw driver and the pink pearl eraser, also known as fix the &&^%^&* keyboard.

Druid6900
March 23rd, 2009, 08:25 PM
At least that's what the working one does; on the nasty one with the seized bearings etc. that I got from my pal in Hamilton (I'm not complaining Dru!) all LEDs come on red and stay that way.



Actually, I never even got a chance to look at it before I gave it to you.

Someone sent it to me to repair, I put it in the pile, 2 days later I get an e-mail saying they found another one and I could keep the one I had, they just wanted me to ship back the IEEE-488 cable (which I now know the price of LOL) and then you got it.