A500 sometimes fail to read disks

_ThEcRoW · 05 July 2005, 15:39

Hello friends, i have to post and tell on the board the behaviour of my beloved a500 some time long ago.

When i turn on the system and put a disk in, sometimes got a read disk errors, and doing a reset could do the trick, sometimes, i need to reboot two or three times to get a disk read. I think that the floppy is nearly to his death, as is a original chinon, i suppose is the original that come with it on factory, or just need some clean or head alignment.
On the other side, a few times i noticed that when i switch the power on, i get a guru message(sorry, not noted the error code, will do it the next time), and it happens even when it has not turned on before, just switching it on an guru. Is possible that the floppy aren´t dying and be a problem of the cias or another custom chip?. I want it to be sorted out, because altough i have other amigas, the 500 is my most preciated machine!!!!.

Any clues? Thanks in advance guys.

Chuckles · 06 July 2005, 08:05

If I'm not mistaken, problems with the floppy drive could be the result of a bad CIA chip, which could also cause problems with other things, such as printing. Without spare CIA chips and/or floppy drives to swap out, I'm not sure how you can tell for sure what the cause is though.

_ThEcRoW · 06 July 2005, 15:44

Maybe trying to reseat the cias should work?

Chuckles · 06 July 2005, 18:00

I wouldn't place a great deal of faith in that solution, but it could work so long as the chip isn't simply fried. Eons ago, I seem to recall being told that an Amiga (at least when the only versions around were A1000, A500 and A2000) should always be left powered off for about a minute or so before powering it back on again, otherwise you risked frying the CIA's. Supposedly plugging anything into any of the ports when the machine is powered on was also running that risk. I don't know how valid those precautions are, but I've always observed them just to be on the safe side, and my CIA's seem to be holding up fine. It never hurts to err on the side of caution.

_ThEcRoW · 06 July 2005, 18:43

Ok, understood, but i haven´t done any of those risky procedures that you describe. It possibly fried due to its age.
And another question i forgot to mention in my first post was that in some moments, the disk drive begins working as if a new disk were inserted, but the disk already in(i don´t change the disk). For example, i boot into workbench and begin typing anything, or just let the computer alone, then sometimes the disk drive comes to work as if a new disk was inserted.
Hope you can understand what i intend to mean, cause my english is not good as i wish.
Thanks in advance!!!!

Chuckles · 06 July 2005, 19:06

Hmmm ... I'm no hardware guru, but that last symptom suggests to me that your problem could be something as simple as a poor power connection to the drive. If the drive intermittently loses power, then when it has none it obviously wouldn't work. When the power comes back, that might explain why the drive would spin up then.

Overdoc · 08 July 2005, 02:01

Your problems are coming from a bad contact on the disk-insertion sensor. This is causing the sudden spinning of the drive and probably also the read errors you get from time to time.

What you need is some electronics-contact-spray. You can get it at any electronic store.

Then, when you look into the drive you can see 2 tiny pins on the left side. One is for detecting if a disk is inserted, the other one is for write protection. Use the contact spray and spray only a very tiny bit into both pins. After that gently push them down e.g. with the help of a screwdriver several times.

This should help and cure your drive problems.

_ThEcRoW · 08 July 2005, 15:19

Thanks Overdoc, these sprays should be available in any electronics shop?
In case of could´n manage to get one, any other form of doing the cleanage?.
Thanks

Overdoc · 11 July 2005, 01:36

Well, some sort of alcohol should do the trick as well

But don't forget to use only a very small drip and then move the pin up and down lots of times to make sure it is cleaning all dirt and make good contact again !

astuermer · 11 July 2005, 02:46

Hi Overdoc
Your name sounds familiar... bought an A500 some years ago from me?
Best regards

Overdoc · 20 July 2005, 02:14

Hehe, yes, but if I remember correctly it was an A-1200 Magic Set, but without ROMS...
Nice to see another fellow from Austria here still using his Amiga !
Also don't forget to visit the Vienna Commodore Meeting, held once every year

lloyd · 28 July 2005, 21:23

I copuld be wrong but - aren't there two CIA chips inside an A500? If so, why not try swopping them around to see if the problem with the floppy drive goes away (only to be replaced with a different problem). At least you'll know then if it's a CIA problem

Chuckles · 29 July 2005, 00:31

Actually, I'm curious whether the problem might have already been fixed at this point. Its been more than 2 weeks since the suggestion was made to clean the contact on the disk insertion sensor, so maybe no news is good news. It would be nice to know though if Overdoc's suggestion fixed the problem.

_ThEcRoW · 06 August 2005, 15:06

Sorry for the delay, but i have been away from the computers a long time because holidays, hehe.
I cleaned the diskchange sensor, but still i´m having the same problems. I think that the drive is dying and the only viable solution is replacing the drive, but a amiga drive here in spain costs me approximately 40 eur(the original chinon of course).
Thanks for the replies, i´ll keep you informed of the progress on resurrecting the drive. If i buy a new drive i´ll tell you.
Thanks!!!!!!

Overdoc · 10 August 2005, 01:22

Well, the sensor was just one of many things that can make a Amiga behave like this when gone bad.
The drive could also have dirty heads or gone slightly out of alignement, or the spindle is slightly stuck.
Aligning the drive is not easy, but you could try cleaning both the upper and lower head with a q-tip and some alcohol. Also, give a tiny drop of oil on the spindle and the rail where the heads slide along.

Also, I think the guru problem could come from something else. If you have a 1MB ram expansion then remove it and check if the gurus are still coming from time to time ?

Also press on every chip to ensure it is firmly sitting in it's socket !
I don't think any chip is bad in your Amiga since they don't die often, but bad chip contact, bad drives and bad Ram expansion contact are the most common problems.

_ThEcRoW · 12 August 2005, 18:37

Thanks overdoc. I will try to see if the chips need a reseating. Ah, i don´t have 1mb only 512kb of chip. It´s a bare 500´s hehe
Hope can upgrade it soon with more ram.

05 July 2005, 15:39	#1
_ThEcRoW Amiga NetRunner Join Date: Apr 2005 Location: Spain Age: 45 Posts: 942	A500 sometimes fail to read disks Hello friends, i have to post and tell on the board the behaviour of my beloved a500 some time long ago. When i turn on the system and put a disk in, sometimes got a read disk errors, and doing a reset could do the trick, sometimes, i need to reboot two or three times to get a disk read. I think that the floppy is nearly to his death, as is a original chinon, i suppose is the original that come with it on factory, or just need some clean or head alignment. On the other side, a few times i noticed that when i switch the power on, i get a guru message(sorry, not noted the error code, will do it the next time), and it happens even when it has not turned on before, just switching it on an guru. Is possible that the floppy aren´t dying and be a problem of the cias or another custom chip?. I want it to be sorted out, because altough i have other amigas, the 500 is my most preciated machine!!!!. Any clues? Thanks in advance guys.

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06 July 2005, 08:05	#2
Chuckles The Ancient One Join Date: Feb 2002 Location: Kansas City/USA Age: 69 Posts: 685	If I'm not mistaken, problems with the floppy drive could be the result of a bad CIA chip, which could also cause problems with other things, such as printing. Without spare CIA chips and/or floppy drives to swap out, I'm not sure how you can tell for sure what the cause is though.

06 July 2005, 15:44	#3
_ThEcRoW Amiga NetRunner Join Date: Apr 2005 Location: Spain Age: 45 Posts: 942	Maybe trying to reseat the cias should work?

06 July 2005, 18:00	#4
Chuckles The Ancient One Join Date: Feb 2002 Location: Kansas City/USA Age: 69 Posts: 685	I wouldn't place a great deal of faith in that solution, but it could work so long as the chip isn't simply fried. Eons ago, I seem to recall being told that an Amiga (at least when the only versions around were A1000, A500 and A2000) should always be left powered off for about a minute or so before powering it back on again, otherwise you risked frying the CIA's. Supposedly plugging anything into any of the ports when the machine is powered on was also running that risk. I don't know how valid those precautions are, but I've always observed them just to be on the safe side, and my CIA's seem to be holding up fine. It never hurts to err on the side of caution.

06 July 2005, 18:43	#5
_ThEcRoW Amiga NetRunner Join Date: Apr 2005 Location: Spain Age: 45 Posts: 942	Ok, understood, but i haven´t done any of those risky procedures that you describe. It possibly fried due to its age. And another question i forgot to mention in my first post was that in some moments, the disk drive begins working as if a new disk were inserted, but the disk already in(i don´t change the disk). For example, i boot into workbench and begin typing anything, or just let the computer alone, then sometimes the disk drive comes to work as if a new disk was inserted. Hope you can understand what i intend to mean, cause my english is not good as i wish. Thanks in advance!!!!

06 July 2005, 19:06	#6
Chuckles The Ancient One Join Date: Feb 2002 Location: Kansas City/USA Age: 69 Posts: 685	Hmmm ... I'm no hardware guru, but that last symptom suggests to me that your problem could be something as simple as a poor power connection to the drive. If the drive intermittently loses power, then when it has none it obviously wouldn't work. When the power comes back, that might explain why the drive would spin up then.

08 July 2005, 02:01	#7
Overdoc Commodore Collector Join Date: Aug 2001 Location: Austria Age: 53 Posts: 944	Your problems are coming from a bad contact on the disk-insertion sensor. This is causing the sudden spinning of the drive and probably also the read errors you get from time to time. What you need is some electronics-contact-spray. You can get it at any electronic store. Then, when you look into the drive you can see 2 tiny pins on the left side. One is for detecting if a disk is inserted, the other one is for write protection. Use the contact spray and spray only a very tiny bit into both pins. After that gently push them down e.g. with the help of a screwdriver several times. This should help and cure your drive problems.

08 July 2005, 15:19	#8
_ThEcRoW Amiga NetRunner Join Date: Apr 2005 Location: Spain Age: 45 Posts: 942	Thanks Overdoc, these sprays should be available in any electronics shop? In case of could´n manage to get one, any other form of doing the cleanage?. Thanks

11 July 2005, 01:36	#9
Overdoc Commodore Collector Join Date: Aug 2001 Location: Austria Age: 53 Posts: 944	Well, some sort of alcohol should do the trick as well But don't forget to use only a very small drip and then move the pin up and down lots of times to make sure it is cleaning all dirt and make good contact again !

11 July 2005, 02:46	#10
astuermer Registered User Join Date: May 2005 Location: Austria Age: 46 Posts: 118	Hi Overdoc Your name sounds familiar... bought an A500 some years ago from me? Best regards

20 July 2005, 02:14	#11
Overdoc Commodore Collector Join Date: Aug 2001 Location: Austria Age: 53 Posts: 944	Hehe, yes, but if I remember correctly it was an A-1200 Magic Set, but without ROMS... Nice to see another fellow from Austria here still using his Amiga ! Also don't forget to visit the Vienna Commodore Meeting, held once every year

28 July 2005, 21:23	#12
lloyd Mehh :D Join Date: Nov 2004 Location: Bristol, SW UK Age: 61 Posts: 242	I copuld be wrong but - aren't there two CIA chips inside an A500? If so, why not try swopping them around to see if the problem with the floppy drive goes away (only to be replaced with a different problem). At least you'll know then if it's a CIA problem

29 July 2005, 00:31	#13
Chuckles The Ancient One Join Date: Feb 2002 Location: Kansas City/USA Age: 69 Posts: 685	Actually, I'm curious whether the problem might have already been fixed at this point. Its been more than 2 weeks since the suggestion was made to clean the contact on the disk insertion sensor, so maybe no news is good news. It would be nice to know though if Overdoc's suggestion fixed the problem.

06 August 2005, 15:06	#14
_ThEcRoW Amiga NetRunner Join Date: Apr 2005 Location: Spain Age: 45 Posts: 942	Sorry for the delay, but i have been away from the computers a long time because holidays, hehe. I cleaned the diskchange sensor, but still i´m having the same problems. I think that the drive is dying and the only viable solution is replacing the drive, but a amiga drive here in spain costs me approximately 40 eur(the original chinon of course). Thanks for the replies, i´ll keep you informed of the progress on resurrecting the drive. If i buy a new drive i´ll tell you. Thanks!!!!!!

10 August 2005, 01:22	#15
Overdoc Commodore Collector Join Date: Aug 2001 Location: Austria Age: 53 Posts: 944	Well, the sensor was just one of many things that can make a Amiga behave like this when gone bad. The drive could also have dirty heads or gone slightly out of alignement, or the spindle is slightly stuck. Aligning the drive is not easy, but you could try cleaning both the upper and lower head with a q-tip and some alcohol. Also, give a tiny drop of oil on the spindle and the rail where the heads slide along. Also, I think the guru problem could come from something else. If you have a 1MB ram expansion then remove it and check if the gurus are still coming from time to time ? Also press on every chip to ensure it is firmly sitting in it's socket ! I don't think any chip is bad in your Amiga since they don't die often, but bad chip contact, bad drives and bad Ram expansion contact are the most common problems.

12 August 2005, 18:37	#16
_ThEcRoW Amiga NetRunner Join Date: Apr 2005 Location: Spain Age: 45 Posts: 942	Thanks overdoc. I will try to see if the chips need a reseating. Ah, i don´t have 1mb only 512kb of chip. It´s a bare 500´s hehe Hope can upgrade it soon with more ram.

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