Strange A1200 behaviour
 

One of my friends got an A1200 from eBay. It is a model made out during the ESCOM years that is mobo 1 D4 and 3.1 Roms. It is the Desktop Dynamite pack.

The strange thing is that it takes nearly 10 secs until you see the Amiga's boot screen with the floppy disk animation. Never seen an A1200 before that it takes so long.

Second problem I have, is that certain games fail to load whereas the same games work perfectly in every single Amiga I tried including my A1200. A game that I experienced problems is Kick Off 2.

I thought to replace the ROMS with the 3.0 ones (I have a spare set). I replaced them and the result is exactly the same. Still takes ages to get the boot screen and games fail to load (I tried 3-4 games and two of them didn't work).

What can be wrong? I mean, I tried the original Kick Off 2 disk that comes with a boot disk that is supposed to make the game work in every single Amiga out there and still, this A1200 is probably the only Amiga that this game failed.

Can this be a disk drive problem? I tried to connect the disk drive from my fully functional amiga (a mitsui one) to the 'strange' A1200 (it has a panasonic fdd) but it didn't work with it. Then I tried to take my external fdd out of the case and connect it to this Amiga and it was not working either (it was like reading the first track and then going back to the boot screen with the process continue in an endless loop). Thing is that the Panasonic fdd reads many disks already, so I think it may not be it. The Kick Off disk starts to boot and fails after 5-10 secs.

Any suggestions guys? It is really annoying. I took the mobo out last night but couldn't see anything wrong with it.

Re: Strange A1200 behaviour
 

An A1200 without a hard disk takes about that long to start up. The hard disk detection routines hold everything up until the system is sure that no hard drives are attached.

Kickstart 3.1 ROMs take slightly longer than 3.0.

The Escom/Amiga Technologies A1200s used a standard PC high-density floppy drive, bodged to work as an Amiga double-density drive. Unfortunately, the drive doesn't implement the DISK_WAIT signal, which is used by the majority of Amiga games. Without this, games will freeze and wait indefinitely for a signal which will never be delivered.

I tried installing a standard Amiga floppy in my Escom machine, but had the same result as you. It's possible that Escom bodged something on the motherboard to make the drives work, which makes standard drives fail; alternatively, did you try swapping the floppy's ribbon cable? I didn't try that, and they may be different.

Yes, I took off the whole thing that is FDD + cable off my A1200 and installed it to the other A1200.

All I noticed is that the ESCOM A1200 FDD has a pin less than the others. Could that be it? Not sure.

Anyway, it is a bit annoying really. I am not even sure if it is the FDD, just made a speculation.

There is a way to cure EFDS (Escom Floppy Drive Syndrome), unfortunately I can't remeber how :(

Try searching the hardware hacks section of aminet.

I think I've seen something about it. I think it has to do with a PCB that ESCOM used in order to connect HD FDDs to A1200. I have to look after that PCB and remove it or something like that...

http://ftp.wustl.edu/pub/aminet/hard...A1200FDfix.lha

Have fun !

Why did ESCOM resort too using a pc floppy to begin with? Saving a few pennies while making the machine incapable of playing most of its software base isnt smart.

Jeez! Thanks guys, that should be it! I can't think of anything else really... Now, this is hacking time! :guru

ESCOM used HD drives because they were easier to source, and probably cheaper.

We will be providing a very clean way to make these ESCOM Amiga's drive systems 100% compatible with normal Amiga's with just a couple of wire mods very soon if you are interested...

The original Amiga drives were no longer being manufactured, so Escom didn't really have much choice.

I assumed commodore had some stock of their standard drives when they went bust.

Is it easy to hack a cheap hd drive to use with amiga's that had the original drive?

My a1200 is a commodore original and knock on wood still works fine, still nothing mechanical lasts forever

ant512: Yes, that would be a bit of a problem ;)

It is a shame they did not do a little more research, they could have made their systems compatible rather easily with the drives they were using.


Unknown_K: Unfortunately, every drive is different, and the hack we have for the HD drive that comes with the ESCOM A1200's is not always the same for other drives.

Of course, you could do what ESCOM did to the motherboard and then use any HD drive (AFAIK) but then you would no longer have 100% compatibility.

You can buy an interface that allows you to connect a standard PC HD drive and use it as a fully-functional Amiga drive:

"For Amiga 1200, Amigas with zorro-slots, PCs with ISA Slots

Catweasel is a universal floppy disk controller that uses unmodified PC diskdrives. The Catweasel can handle nearly any disk format, you just have to find a drive for them.

* all PC-formats (180K up to 1440K)
* Amiga DD and HD (also 5,25" formats)
* Atari 9, 10 and 11 sektor disks
* Macintosh 720K, 800K, 1440K (DD, GCR, HD)
* Commodore 1541, 1571, 1581 (C64, C128 and 3,5" C-64 disks)
* XTRA High density with 2380KByte per disk
* Nintendo backup station 1600KB format
* Atari 800XL (all MFM formats, FM under developement)
* Apple IIe disks (Apple DOS 3.3 and up)
* further 8-bit formats planned"

Check http://www.jschoenfeld.com/indexe.htm for more info.

Now, I also found this:

http://uk.aminet.net/pub/aminet/hard...Floppy_fix.lha

So, I am a bit confused. Which one should I use? The former fix talks about a PCB the second about a diode. The games do start to boot but fail afterwards.

Does it matter if the Rom is 3.0 or 3.1?

How about your solution Fiath? Does it apply to specific FDD models and if yes, do you want to send you the FDD model in case it works with mine? You know I love KO2 :D so what do you recommend doing. The PCB board looks easy to make as long as I have the materials...

If your drive is a Panasonic JU-257A605P (which it probably will be with AT A1200's), then then it will work.

All you need to do is change one line on the FDD and change one on the A1200 motherboard.

Nothing dramatic needed. I will try and make the HTML version public today for you (the original is Amiga Guide format).

Yes, that's the one! Okay cool, send me the info 'cos this little bugger distracted me from making those games images I promised to you! :D

Okay, here is the info extracted from our knowledge base. It is basically just a HTML'ised version of something somebody from the team worked on.

http://www.caps-project.org/a1200mod.html

Thanks! :)

Fiath: do you think this mod you talk about could be performed to any HD drive that is connected through a Klylwalda interface?

No, it is FDD specific. You *may* (or may not) be able to do something similar, but unfortuneatly it entirely depends on the drive, and how it works.

It is probably best not trying it with some random drive unless you really know what you are doing, since you may break the drive, or worse, anything it is connected to.

Perhaps I should ask ville9 what things to look for when trying to see if the same technique can be used on other drives...