DDI-1 new belt installed, but after one succes, always read-fail

[Lux]

I got hold of this dusty DDI-1 set and of course the drive failed every way. I replaced the drive belt (inside there was an orange elastic band curled up  ), cleaned the capstan and the read/write head...and -WOW- with the first disk the thing worked: I could load and play a game without any problem (Robocop it was). 

Very pleased with myself and the drive, I tried another disk...fail to read...I tried yet another...fail to read...what??? Every disk I try... fail to read.
If I insert a disk and CAT, the drive spins allright and the read/write head moves over the floppy twice. Then the message appears: (see above).

Please, someone tell me there is just that little thing I forgot to do?

[Bryce]

Are you sure that the disks are good?

Bryce.

[Gryzor]

Does Robocop still run or not?

[Lux]

All disks tested on another machine, they are all OK.
I removed the belt and put it back once again...still read fail , even Robocop.

I forgot to mention the write protect pin is missing, but that shouldn't be of any influence on reading a disk, should it?

And it DID work the very first time.

[arnoldemu]

I got hold of this dusty DDI-1 set and of course the drive failed every way. I replaced the drive belt (inside there was an orange elastic band curled up  ), cleaned the capstan and the read/write head...and -WOW- with the first disk the thing worked: I could load and play a game without any problem (Robocop it was). 

Very pleased with myself and the drive, I tried another disk...fail to read...I tried yet another...fail to read...what??? Every disk I try... fail to read.
If I insert a disk and CAT, the drive spins allright and the read/write head moves over the floppy twice. Then the message appears: (see above).

Please, someone tell me there is just that little thing I forgot to do?

The rails on which the head head is on need to be lubricated.

Another thing I remember is I had a drive that used to do read fail, I would eject it in the middle of the read, and put it back in again and it would then work. not sure why.
Probably only best trying with a disc you are happy to loose.

Another possibility is now the head needs cleaning?

[Bryce]

Good advice.

Generally all moving parts, including the loading mechanism should be greased to make sure the floppy is sitting correctly when it's inserted too.

Bryce.

[Lux]

Cleaned the head, lubricated the drive worm and the rails under the head.
I performed the eject-while-reading trick. Did this a couple of times.


Most of the time these kind of performances surprise me and do the trick, but alas...


...still the same, the head moves two times over the spinning disk and then read fail.

[Bryce]

Did you properly connect all the connectors after you installed the new belt? Maybe one has come loose?

Otherwise the only thing it can be is a mis-aligned head?

Bryce.

[XorA]

Otherwise the only thing it can be is a mis-aligned head?

This should be easy enough to test, format a disk in this machine (after kludging the write protect). Format it and see if it reads!

I have a misaligned drive I really wish I had the patience/expertise to fix but does pretty much the described behaviour on a disk it has not formatted itself.

[Gryzor]

Good point by XorA. But you do need to find/replace that writing pin...

[Lux]

I've managed to fabricate my own write protect pin.


I took the tiniest nail I could find and that fitted the hole. Then I tried and shortened it until the disk could be inserted properly.
OK, so that's fixed!


But, uh...how do I format? Can't read the CP/M disk, so...

[Gryzor]

Damn, there are a couple of formatting programs you can type in, trying to locate them...

[Gryzor]

Ok, credits go to G. Farmer, it appeared in ACU July 1991 and unearthed by DevilMarkus:

Code Select Expand


10 SYMBOL AFTER 256:MEMORY &5FFF
20 FOR A=&7000 TO &7081
30 READ B$:POKE A,VAL("&"+B$):C=C+VAL("&"+B$)
40 NEXT
50 IF C<>13682 THEN PRINT"DATA ERROR":END
60 CALL &7000
70 DATA 01,0A,70,21,17,70,CD,D1,BC
80 DATA C9,0F,70,C3,1B,70,46,41,52
90 DATA 43,41,4C,CC,00,00,00,00,00,DD,7E
100 DATA 0A,32,7F,70,DD,7E,0B,32,80
110 DATA 70,DD,7E,08,32,81,70,DD,6E
120 DATA 00,DD,66,01,7E,DD,6E,02,DD
130 DATA 66,03,4E,23,46,DD,6E,04,DD
140 DATA 66,05,5E,23,56,D5,DD,6E,06
150 DATA DD,66,07,5E,23,56,62,6B,D1
160 DATA DD,E5,DF,7F,70,DD,E1,E5,DD
170 DATA 6E,00,DD,66,01,77,DD,6E,02
180 DATA DD,66,03,71,23,70,DD,6E,04
190 DATA DD,66,05,73,23,72,D1,DD,6E
200 DATA 06,DD,66,07,73,23,72,C9,00
210 DATA 00,00
220 MODE 1:BORDER 0:INK 0,0:INK 1,26:INK 3,6:PAPER 0:PEN 1:PLOT -10,-10,1
230 ENV 1,=11,10,=9,3000
240 DEFINT a-z
250 ORIGIN 0,200
260 FOR r=100 TO 380 STEP 7
270 MOVE r-7,r/4:DRAW r-3,r/8:DRAW r,0:DRAW r-3,-r/8:DRAW r-7,-r/4
280 NEXT
290 DRAW 93,-25:MOVE 93,25:DRAW 374,96
300 LOCATE 5,11:PRINT"0":LOCATE 24,6:PRINT"39":LOCATE 10,9:PRINT"10":LOCATE 15,8:PRINT"20":LOCATE 20,7:PRINT"30":LOCATE 1,1:PRINT"Select option":PRINT"1.Data Format":PRINT"2.System Format":PRINT"3.Exit"
310 i=VAL(INKEY$):IF i<1 OR i>3 THEN 310
320 SOUND 1,200,100,10,1
330 IF i=1 THEN f=&C1
340 IF i=2 THEN f=&41
350 IF i=3 THEN |BASIC
360 LOCATE 11,23:PRINT"Press F to Format":LOCATE 9,24:PRINT"Any other key to abort"
370 i$=UPPER$(INKEY$):IF i$="" THEN 370
380 IF i$<>"F" THEN 220
390 SOUND 1,150,100,10,1:LOCATE 11,22:PRINT SPACE$(70)
400 PLOT -10,-10,3
410 HL=0:DE=0:BC=0:A=0
420 POKE &6FFF,&83:HL=&6FFF
430 |FARCALL,&BCD4,0,@HL,@DE,@BC,@A
440 A=f:DE=0:|FARCALL,HL,7,@HL,@DE,@BC,@A
450 POKE &6FFF,&86:HL=&6FFF
460 |FARCALL,&BCD4,0,@HL,@DE,@BC,@A
470 HLT=HL
480 ADR=&6000
490 TRACK=0
500 FOR P=0 TO 9
510 POKE ADR,TRACK:POKE ADR+1,0:POKE ADR+2,f+P:POKE ADR+3,2:ADR=ADR+4
520 NEXT
530 DE=256*TRACK:HL=&6000:|FARCALL,HLT,7,@HL,@DE,@BC,@A
540 r=100+7*track:MOVE r-7,r/4:DRAW r-3,r/8:DRAW r,0:DRAW r-3,-r/8:DRAW r-7,-r/4
550 TRACK=TRACK+1:IF TRACK<40 THEN ADR=&6000:GOTO 500
560 SOUND 1,30,50,10,1:SOUND 1,30,100,10,1:LOCATE 12,22:PRINT"Format complete":LOCATE 13,23:PRINT"Press any key":WHILE INKEY$="":WEND:GOTO 220


(taken from Simple Format-Routine in Basic . Go there for more details and proper credits)


Also, from RobotPD Disk #12100A (author unknown):

Code Select Expand


1 ' Fast disc Formatter
100 DATA 21,83,90,01,09,90,C3,D1
110 DATA BC,11,90,C3,22,90,C3,1E
120 DATA 90,43,2E,46,4F,52,CD,44
130 DATA 2E,46,4F,52,CD,00,3E,C1
140 DATA 18,02,3E,41,32,82,90,0E
150 DATA 00,3E,02,21,92,90,CD,73
160 DATA 90,21,80,90,CD,D4,BC,D0
170 DATA 22,8A,90,79,32,8C,90,21
180 DATA 7E,90,CD,D4,BC,D0,ED,5B
190 DATA 81,90,7A,D5,CD,1B,00,D1
200 DATA 7A,0E,01,21,91,90,CD,73
210 DATA 90,01,00,28,3E,28,90,57
220 DATA 21,8F,90,C5,E5,0E,00,CD
230 DATA 73,90,E1,C1,DF,8A,90,D0
240 DATA 10,EA,C9,06,09,77,23,23
250 DATA 23,23,81,10,F8,C9,83,84
260 DATA 86,00,C1,00,00,00,00,00
280 DATA end
290 '
300 MODE 2:chk=0:x=&9000:MEMORY x-1
310 READ a$:IF a$="end" THEN 330 ELSE a=VAL("&"+a$)
320 POKE x,a:x=x+1:chk=chk+a:GOTO 310
330 IF chk<>&3904 THEN PRINT "DATA ERROR.":END
340 CALL &9000
350 PRINT"|D.FORM = format DATA discs       |C.FORM = format CPM discs"


[Lux]

Succeeded in formatting a disk (think so, because running the program, it created the appropriate noises).
Then tried CAT....read fail
Then tried to SAVE...read fail (not write fail)




Guess it ends here?

[Gryzor]

Well, I wouldn't stop at one disk, maybe the disk is defective anyway?

[Lux]

Tried several disks, they all formatted allright...
but then...read fail

[Bryce]

Then it can only be a break somewhere on the read line or the read head is damaged.

Bryce.

[Lux]

Time to give up trying I guess.
But well, I now at least have a floppy drive for formatting only.

[Gryzor]

Well, *if* it's formatting indeed, you'll need to test the disk in another drive.

[Bryce]

If it's important enough for you, then send it over to me (in Germany). I can check it out for you. When we know what's wrong, you can decide whether it's worth fixing or not.

Bryce.

[Lux]

Gryzor, the damn thing fooled me with its pretend-to-be-formatting noises; it does not format indeed.
Bryce, do you think it's worth the effort (and costs)?

I tend to put this little project aside for a while, but I had quite some fun with it so far:
I am able to dismantle a drive and replace a belt even blindfolded by now and I produced my own little write-protect pin! And I know how to format without cp/m!

[Bryce]

Whether it's worth the bother and cost can only be decided by you. If it's your original FD-1 from way back in your childhood and your only way to load the 50 3in disks you own, then I'd say yes. If it is one of the 3 FD-1s you bought on ebay for €10, then it's probably not worth it (at the moment).

Bryce.

[Lux]

No...no FD's in my childhood, let alone a CPC. No homecomputer, no calculator, I only remember this wooden abacus.


Anyway thanks a lot all!


Great forum, keep up the good work!

[Gryzor]

You can write an article about the abacus in the wiki, you know!


A very misunderstood tool, the abacus. Most people think it's really basic and for small kids only, since that's where we use it. Until you see a Chinese keeping his company's accounts with one

[Bryce]

Was it an Amstrad abacus?

There are "virtual abacus" programs for the PC, can we have one for the CPC too please?

We learnt to multiply and divide with them in primary school

Bryce.