A1200 no picture...

[hikey]

repair/refurbishment is a better option in my opinion, otherwise you could well just keep buying boards that need work doing to them now or in the near future.
Despite that you have no video on your A1200, is the machine actually working - ie, will the drive actually respond and start loading if you put a bootable disk in?

 

[TheoryBoy]

If you go for a replacement motherboard, you will need a 2B version otherwise the floppy drive you have wont work. But the 2B is the lesser desirable version so you might get it cheaper than other revisions.
If you do go for a different version you will have to get a floppy drive also.

 

[AmiNeo]

No theres no response from the floppy atall when a bootable disk is in the machine. It clicks once regardless of whether there is a disk or not in it when the power is turned on though but thats all.

I kinda agree with the refurbishment thing but if it turns out its more than just caps...

What a dialema lol. :roll:

---------- Post added at 09:19 ---------- Previous post was at 09:15 ----------

Floppy drives are motherboard specific?!? I wonder if thats why theres no response from this one...

 

[scrappysphinx]

i also didnt know floppy drives were specific to motherboards, i thought that a floppy drive was a floppy drive and would work with any revision motherboard

 

[AmiNeo]

Evilbay Airey got back to me and said he doesnt test them beyond booting, so couldnt garantee anything.

Buying one from him could land me in the same boat if caps is the only problem.


And may i ask why the 2B is the least desirable? :dry:... lol

---------- Post added at 09:39 ---------- Previous post was at 09:28 ----------

i also didnt know floppy drives were specific to motherboards, i thought that a floppy drive was a floppy drive and would work with any revision motherboard

Yea, i could understand 1200s not working with 600s or something but 1200s not working on 1200sl!? I'd like to know why that is...

 

[TheoryBoy]

The A1200 was sold by two companies over its life time, Commodore which went *pooff* and later Escom / Amiga Technologies. The 2B could be the Escom revision of the A1200 as opposed to Commodore for the previous revisions. Escom uses a modified PC floppy drive which can cause some incompatibilities as the modification was both board level and at the drive. Then there is the issue of accelerators and 2B compatibility which affect the boards value.

 

[scrappysphinx]

I thought the escom board was 1.d4 board?
and even though they used modified pc drives i still believed they worked on all revisions?

 

[TheoryBoy]

AFAIK the Escom 1200 floppy drives were missing the _RDY signal, so the board had to be modified to suit. If you use an Escom floppy drive on an earlier board I would think that some game bootloaders and maybe xcopy might not work properly.

From reading around the last of the 1.d4 s were sold to escom which they modified to work with pc drives and the 2b is a fully escom revision.


The 2B can be modified to work with standard amiga floppy drives though.
http://www.softpres.org/article:hard:fixing_the_amiga_technologies_a1200_fdd_connector

 

[AmiNeo]

AFAIK the Escom 1200 floppy drives were missing the _RDY signal, so the board had to be modified to suit. If you use an Escom floppy drive on an earlier board I would think that some game bootloaders and maybe xcopy might not work properly.

From reading around the last of the 1.d4 s were sold to escom which they modified to work with pc drives and the 2b is a fully escom revision.


The 2B can be modified to work with standard amiga floppy drives though.
http://www.softpres.org/article:hard:fixing_the_amiga_technologies_a1200_fdd_connector

Intersting, i was aware of the manufacturing history of the 1200 as per the ESCOM reproduction but never knew they changed this much...

---------- Post added at 11:52 ---------- Previous post was at 10:39 ----------

Hey scrappy, your parcel just arrived...

New ROM new Cable, same problem... :|


Just to clarify, nothing changed, lol. I am getting the same output as with the composite cable, and the ROMs didnt change a thing...

 

[scrappysphinx]

@AmiNeo sorry bud thought the video port might have worked.
Looks like your either after a new board or someone to repair yours.

 

[AmiNeo]

Ok, no probs, you want the bits back bud?

 

[scrappysphinx]

you can keep em if you like, i only kept them as spares for testing machines i buy so i don't have to keep disconnecting my main machine

 

[AmiNeo]

Ok well i appreciate it, im sure they'll come in handy.

If you ever need em back just holler

 

[Justin]

i still think the board needs some work after the roms were moved from board to board etc

 

[AmiNeo]

What you mean Juv?

---------- Post added at 12:24 ---------- Previous post was at 12:23 ----------

Telling someone theyre doing it wrong isnt helpful unless you say why, lol

 

[Justin]

from what i've read in this thread, A600 rom was plugged into the A1200 board and visa versa, you don't seem to be completely sure of the orientation, i have killed a mobo in the past by fitting the roms correctly, that's all i'm saying

cheers, JuvUK

 

[Zetr0]

@AmiNeo

I truly hate seeing this thread go on without resolve =(

I cannot promise anything - but I think I can help you out - however time is pretty damn pressed for me.

I have sevearly things to sort out and these would come first.

2x A1200 timing fixes - Blankstare
1x A600 2MB Chip Piggy Back - Juv
1x MiniMig - Arnljot
1x 030 track repair
2x A4000 motherboard repairs (caps and logic)- Juv UK / Me
3x A1200 motherboard recaps - ME
A2000 PSU rebuild - ME
A2000 Hybrid Build - ME (on hold - waiting components =()
*(Special suprise for TokyoRacer)*

If you can wait. then hit me up on PM, we can see what we can do on the cheap.

 

[TheoryBoy]

I think the only thing now is to make a good visual inspection of the board, checking for bent chip legs, traces of capacitor leaks, broken traces. especially checking the legs of chip at U4 (the one marked hp) in case of improper indivision installation in the past.

Other than that.. well another board I'd say


Oh an Zetr0 as I have you here, there is no need to send me that a500 zorro adaptor, I ordered one from tom with a different zorro card.

Cheers

 

[AmiNeo]

from what i've read in this thread, A600 rom was plugged into the A1200 board and visa versa, you don't seem to be completely sure of the orientation, i have killed a mobo in the past by fitting the roms correctly, that's all i'm saying

cheers, JuvUK

You can kill a motherboard by incorrectly installing 2 EPROM chips in the wrong places? How does that work?

With them not even initialising however i doubt it has changed anything either way.

---------- Post added at 12:49 ---------- Previous post was at 12:42 ----------

For the record i wasnt stupid enough to put them in backwards or in the wrong pin holes... As far as im aware an EPROM shouldnt damage anything if its in the correct place even if the data is incompatable?

---------- Post added at 12:50 ---------- Previous post was at 12:49 ----------

@AmiNeo

I truly hate seeing this thread go on without resolve =(

I cannot promise anything - but I think I can help you out - however time is pretty damn pressed for me.

I have sevearly things to sort out and these would come first.

2x A1200 timing fixes - Blankstare
1x A600 2MB Chip Piggy Back - Juv
1x MiniMig - Arnljot
1x 030 track repair
2x A4000 motherboard repairs (caps and logic)- Juv UK / Me
3x A1200 motherboard recaps - ME
A2000 PSU rebuild - ME
A2000 Hybrid Build - ME (on hold - waiting components =()
*(Special suprise for TokyoRacer)*

If you can wait. then hit me up on PM, we can see what we can do on the cheap.

Hey Zetr0, I'd really appreciate that bud. let me check a few more places and if i get no joy i'll send you a PM.

 

[AndyLandy]

For the record i wasnt stupid enough to put them in backwards or in the wrong pin holes... As far as im aware an EPROM shouldnt damage anything if its in the correct place even if the data is incompatable?

In my experience, if you correctly plug in an EPROM with the wrong data, the Amiga won't boot but no damage should be done. If you plug in the EPROM incorrectly, you're quite likely to kill the EPROM, but shouldn't do any permanent damage to the board. Still, killing EPROMs is annoying and every ROM change is putting wear-and-tear on the ROM socket.