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Re: DiagROM for ST

Posted: 11 Feb 2019 08:01
by terriblefire
not sure how your setup is working but I had to byteswap the rom image to get it to work on the Amiga. My ST setup has hi and lo roms.

Re: DiagROM for ST

Posted: 11 Feb 2019 15:31
by PaulJ
I'm burning the file as is into a 16 bit eprom. I do the same for TOS which I have compared to. Both files have the text readable which means both files are not byte swapped. I have done a byte swap and attempted execution with the same results. Out of curiousity what did you use to assemble the code? This is really strange..has to be something stupid...

Re: DiagROM for ST

Posted: 11 Feb 2019 16:01
by terriblefire
It was assembled with vasm. The code is assembly anyway.

Re: DiagROM for ST

Posted: 11 Feb 2019 16:21
by terriblefire
Try using the rom with Hatari before going any further

Re: DiagROM for ST

Posted: 11 Feb 2019 17:35
by PaulJ
Good idea, I'll give it a try.

Re: DiagROM for ST

Posted: 11 Feb 2019 18:11
by PaulJ
Hmmm.. didn't expect that... works fine with Hatari.. well at least I know I'm working with a functional image... and good hardware.. hmmm guess I'll have to figure this one out.
DM.jpg

Re: DiagROM for ST

Posted: 11 Feb 2019 18:17
by PaulJ
Exxos, out of curiosity does your fast rom adaptor have the high byte in the most significant byte of the word? Guess its time to try 8 bit roms.

Re: DiagROM for ST

Posted: 11 Feb 2019 18:25
by exxos
PaulJ wrote: 11 Feb 2019 18:17 Exxos, out of curiosity does your fast rom adaptor have the high byte in the most significant byte of the word? Guess its time to try 8 bit roms.
Low bytes are first. So it goes LO HI LO HI. Nothing has been swapped out with them.

Re: DiagROM for ST

Posted: 11 Feb 2019 19:34
by PaulJ
Yes, that what I would expect.

The actual memory dump from DiagROM on Hatari looks just like the image which I would expect.
DR2.jpg
Just looked through my roms for a 128k, 256k 120ns or better and came up short. Only roms I found were 200ns. Don't think that will cut it. Have to put some on order.

Re: DiagROM for ST

Posted: 12 Feb 2019 00:53
by PaulJ
Problem solved, had 2 HN27C4096 120ns eproms I got off eBay from China. One died in September last year. With the remaining chip it came down to the swapped byte image I tried in the bad half of the eprom rom over and over. It was programmed on two differient eprom programmers with no faults but the upper half of the eprom will not boot any image. Swapped bytes in the lower half and it work.. All this because I didn't want to make a first attempt in a one burn only chip. Shesh!!!

Thanks