Amiga 1000 Kickstart Eproms/Roms

[Jeff]

I have 3 Amiga 1000's and one of them came to me with Kickstart 1.2 in Rom. Here is what the boot Roms look like. Did the dealer do this, or did it come from the factory like this? The labels look original to me.

Amiga 1000 Kickstart Roms

I would like to program a set of 1.3 Eproms for one of my other machines. Is this a simple ODD-EVEN Split with a byte swap (from a 256k binary file) between a pair of 27256 Eproms or is it more difficult than that?

What about 2.x or 3.x, I assume that would take additional hardware as it is a 512k Kickstart?  If so, has anyone here successfully built this hack?

I have the stuff to erase and program my own Eproms as well as legit originals of all the OS versions (see my photo album). It would be nice to retire my Kickstart floppies:-)

Thanks for any advice.
Jeff

[CLS2086]

Hi,
would you check the difference between your mobo and this photo :
http://amiga-hardware.com/download_photos/a1000mbrev6.jpg
It seems that you have just 2 straps around W2 and W4 that enable the presence of the ROMs.
If you disable these straps, do you get back to the good old KICKSTART hand's screen ?

Try to dump the 2 roms, it's the only way to know if it's splitted by :
1st method : 16 bits word splitted in 2x 8bits word (1st in EVEN, 2nd in ODD... or may be the inverse !)
2nd method : simply divided in the 2 roms.

[Zac67]

68k is big-endian, so the even address bytes are the high, odd the low bytes. The ROMs must be split in two ways byte-wise and in half (FC0000-FDFFFF and FE0000-FFFFFF).

[Jeff]

Thanks! I'll do some more checking and get back with the info. The thing is, it looks like the extra pair of Eproms that were added are in locations U2N and U2P and I think they are soldered in on my board (not sure why they didn't use sockets). I may not go to the trouble to remove them just to dump them. I'll probably just start with another motherboard and some blanks Eproms using Zac67's information and see if it works first. I know I won't fry anything if the data is programmed wrong the first time or two. Good thing I have a few 1000's:-)

@CLS2086
Good eyes! I hadn't even noticed the 2 jumpers.

Jeff

[CLS2086]

I hope you'll get success in your research, i'm not sure that would get better than kick 1.3. And I also think that you'll need to dump the 2 others roms.

I wonder about the 2 jumpers, if they are "open" may it turn back to a "standard" A1000 ?

[rkauer]

 Just a hint: the earlier versions of Amiga itself (= A1000, 500 and 600) have only one ROM chip, even for 3.1 version.

 So they use a "special" version of the ROM, without some functionalities (SCSI.device for A1000/500, for example).

 Try to find a 3.1 ROM image suitable for your A1000.:eureka:

[Zac67]

2.x+ need 512K - you need larger EPROMs and make sure the pinout is OK.

[djbase]

What about 2.x or 3.x, I assume that would take additional hardware as it is a 512k Kickstart?  If so, has anyone here successfully built this hack?

I have an adapter which replaces Even/Odd and gives you a socket for a normal A500 Kickrom.

[TjLaZer]

So those 4 sockets are for ROM upgrades???  I guess they are 27C512 chips?

[Jeff]

@CLS2086
I pulled the jumpers at locations W2 and W4 and the machine won't boot (black screen), put them back in and it boots to a Workbench 1.2 prompt.

@DJBase
PM Sent for information about your adapter.

@Everyone
I guess the next step would be to pull the chips at locations U5N and U5P (since they are socketed) and see if they compare to the same chips in my other machine by reading them in to the eprom programmer. If they are the same and I can't find DJBases adapter, then I'll start working on some eproms for the empty locations in my other machines or build my own adapter.

Thanks,
Jeff

[amigaksi]

>I would like to program a set of 1.3 Eproms for one of my other machines. Is this a simple ODD-EVEN Split with a byte swap (from a 256k binary file) between a pair of 27256 Eproms or is it more difficult than that?

I programmed the amiga end of MPDOS into the ROMs of an Amiga 1000 using a standard a1000 motherboard (picture as given by CLS2086).  I used a pair of 27C256.  The ROM on the left in the picture contains the even bytes (D8..D15) and the ROM on the right contains the odd bytes (D0..D7).

[TjLaZer]

a 27c256 is a 32k chip.  So how are 4 chips holding Kickstart 1.2? (256k)

[TjLaZer]

You know, these 4 chips looked familiar, so I just checked my Amiga chip stash bin and guess what?  I have these 4 chips and I did not know what they were for!  I copied them with my programmer.  So what do I need to do to get this working on my A1000?  Is there a way I can test the images to see if they are a valid kickstart?

[Piru]

Is there a way I can test the images to see if they are a valid kickstart?

Merge the files and check the contents, look for "AMIGA ROM Operating System"?

[TjLaZer]

Tried and could not get it to work. (merged odd/even and combined files)

-edit-
I was right, these chips are 27C512!!!