Expansion 5.25 drive seek fail - Data read error

[Blurredman]

Hi guys,

So after dusting off my 6128 and connecting my 2nd disc drive- namely a TEAC FD55-FGR, which I adapted with three switches in a nice little caddy to accomodate the priority, disc side and 40/80 track selection, I find that it isn't working.

Disc drive in the AMS is working nicely, esspecially after a quick clean but the TEAC isn't liking it at all!

I can select |B but if I try to categorise the contents, the drive does two seeks and fails on 'Data read error'.

I have a similar issue with a spare 3" drive so hoping that any help with the above drive would help me fix the 3" drive too..


The price of 5.25" drives these days has rocketed, so I would really want to fix the above drives than replacing them. I do have a 5.25" Mitsubishi but it doesn't seem like it is compatable with the AMS.



I've cleaned the TEAC heads, made sure jumpers are good for example (RY) and that 40 track is selected..I've even unsoldered the resister that controls 40/80 track selection altogether but other than the two full disc seeks it fails.

I've tried IMD118 Alignment check, but that checks out all good! But reading any disc I get sector read errors. I have around 50 5.25" discs and none of them work, so it's not the discs.


Any help would be appreciated- I've covered all avenues which I would go down.
Thank you.

[Audronic]

@Blurredman


Try cleaning the RAILS for the head and re Lubricating.
The problem could be the head is not reaching the desired track ?
also if you have not done this clean the heads ?


Good luck.   Ray

[Blurredman]

Hi,

Thanks for the reply, Ray.


It seems I am getting somewhere, and that upon my attempt to get it working I have done various things with jumpers that would stop it working.

I'm looking at my previous topics and using my own information have te drive working 'sometimes'.

http://www.cpcwiki.eu/forum/amstrad-cpc-hardware/5-25'-disk-drive-on-6128/msg26222/#msg26222

I do however find the drive very un-reliable.

Most of the time it does Categorise a disc, but upon reading the data is unreliable. sometimes will, sometimes won't. And when it won't it will do a two cycle seek thing, And once it fails reading the data, the amstrad and external disc need to be turned off and on again, a couple of times sometimes until the drive can CAT again.

I'll make a video.


I've cleaned the heads at least- as mentioned in the first post.

[tjohnson]

Are you sure the drive is aligned?  I spent ages and I mean ages aligning a 3.5" drive, if the alignment check works in IMD118 under MS-DOS can you read and write disks in it afterwards?  I had to adjust the top head and the motor position, I don't know how these old 5.25" drives work but it can take a while to get it all fully aligned and reliable.

[Blurredman]

Are you sure the drive is aligned?  I spent ages and I mean ages aligning a 3.5" drive, if the alignment check works in IMD118 under MS-DOS can you read and write disks in it afterwards?  I had to adjust the top head and the motor position, I don't know how these old 5.25" drives work but it can take a while to get it all fully aligned and reliable.

I could try again, but no I couldn't read/write MS-DOS discs, bearing in mind I don't have any 360k discs, only 1.2 compatable discs, which hasn't been a problem in the Amstrad before when 'burning' images to 40 track double step. That said, it seems not to work at all with factory defaults (straps and re-solder resistor R19 (which unsoldering forces 40 tracks)). I have tried, but discs say they are unreadable or unformatted. If i've been able to successfully format them (not many though) and copy some files onto them, my other PC with 1.2m drive reads the disc with information on it 'pre-formatted', so it sees different files to that which the TEAC drive does... It does point to mis-alignment, but the alignment check on IMD118 was beeping away quite merily successfully?

[tjohnson]

I could try again, but no I couldn't read/write MS-DOS discs, bearing in mind I don't have any 360k discs, only 1.2 compatable discs, which hasn't been a problem in the Amstrad before when 'burning' images to 40 track double step. That said, it seems not to work at all with factory defaults (straps and re-solder resistor R19 (which unsoldering forces 40 tracks)). I have tried, but discs say they are unreadable or unformatted. If i've been able to successfully format them (not many though) and copy some files onto them, my other PC with 1.2m drive reads the disc with information on it 'pre-formatted', so it sees different files to that which the TEAC drive does... It does point to mis-alignment, but the alignment check on IMD118 was beeping away quite merily successfully?

For use on a PC set the drive "DS1" and "drive change".  For use on as B drive on CPC set "DS1" and "Ready" or if A drive on CPC set "DS0" and "Ready". 

If the drive is reasonably well aligned it should be possible to format a disk under MS-DOS and then copy/read content.  Try that if possible then move to the CPC.  IS this a single side drive?  Using IMD118 do you get reliable read out across all tracks? Track 0 to 79?  There should be no dropped sectors once it had found the track and depending on the format should ready out the sector number something like 9,4,9,4,8,3,8,3,7,2,7,2,6,1,6,1,5,1,5,9,4.
There seems to be various "straps" I presume more commonly known as jumper or switches on the drive and the LG and I Strap and pin 2 combi nations seems to have some impact on the motor speed.  Check the speed the drive is spinning, I think it needs to be 300rpm for the Amstrad but its possible it is spinning too fast at 360rpm.  Try the program RPM to check the rotation speed.
From what I can work out, to spin the drive at 300rpm I strap needs to be on, LG strap needs to be off with pin 2 pulled low, or on with pin 2 pulled high.

Manual here http://deramp.com/downloads/floppy_drives/teac/TEAC%20FD-55GFR.pdf
The last time I used a 5.25" was on a BBC Micro at school in the 1980s

[Blurredman]

I think the TEAC drive is 'ffffed'. I found track membrane break to the side 2 head. I don't see why that stopped me from 'occasionally' reading side 1.

But i'm using a Mitsubishi MF504C-318UG in my caddy now.

This drive has the advantages of not requiring any soldering, but only using jumpers I got it working nicely.
Force 300rpm, force DD instead of HD, force ready signal. All that was required.


As mentioned in one of my posts in the past.
http://www.cpcwiki.eu/forum/amstrad-cpc-hardware/5-25'-disk-drive-on-6128/

As per the attachment. Move:

Jumper from DC to RY (Ready Signal)
Jumper from SB to SS (Speed)
Attach new jumper to SS/ND (capacity)


I can at least access my AMSTRAD discs, but of course I would have to modify a 3.5" disc drive if I didn't find a 5.25" for the PC to transfer data. I do have an AMSTRAD 1512 however- I could nick one of the 360k drivs from that... 

Disapointed and a little upset. I've had that TEAC drive for 15 years..