H8 Default Regs for Segments?

Ceddy · 16-06-2009, 11:47 PM

Hello everyone,

I saw some people are working on the H8(Evo5/6) ecus here.

I've made some good progress with my disassembly, but have run into one major roadblock. I can't get the default registers for different segments setup right.

The absolute addresses (@F000) will always be off by 10000 in one of the segments.

I have:
10000-20000 as segment 1, and dp=1, br=0
20000-30000 as segment 2, and dp=2, br=0

I've tried lots of different numbers but can't get it right.

If anyone has worked on this or has any insights, any help would be greatly appreciated.

Thanks very much.

MattS00 · 17-06-2009, 05:45 AM

I'm really new to this, but I've seen something that may be similar, but I have not been able to figure out. I don't have a Evo 5/6/6.5, but I have a 2000 eclipse with a MH7203FA processor just like the e6.5 and I guess the AYC controller in other evos.

On the xml for my rom the rom id is at address 1021a. I then use dasmh85.exe to open the rom. The memory range is from 0000 to ffff. If I type in the address of 021a the rom id is at that location, and there is no 1021a.

What program do you use to open the rom to view it?

Ceddy · 17-06-2009, 06:47 AM

The H8s are offset +10000. So you need to add 0x10000 to your hex editor address.

And to answer my own question above.
The H8s are single chip mode(mode 7). There are three segments, but dp=0 for all of them.

Also 10000-14000 is mirrored at 0-4000. I was confusing the low number addresses with a bad absolute address.

Memory address 00000-03FFF = ROM 00000-03FFF (Seg 0)
Memory address 14000-1FFFF = ROM 04000-0FFFF (Seg 1)
Memory address 20000-2FFFF = ROM 10000-1FFFF (Seg 2)
RAM EE80-FE7F
REGS FE80-FFFF
4000-EE7F is Unused

MattS00 · 17-06-2009, 07:42 AM

What program do you use to open the rom?

I think I'm really over my head here. I'm only catching bits and pieces of what I read. Is this what you are talking about?

16-06-2009, 11:47 PM	#1
Ceddy Member Join Date: Apr 2009 Location: Pennsylvania Posts: 85	H8 Default Regs for Segments? Hello everyone, I saw some people are working on the H8(Evo5/6) ecus here. I've made some good progress with my disassembly, but have run into one major roadblock. I can't get the default registers for different segments setup right. The absolute addresses (@F000) will always be off by 10000 in one of the segments. I have: 10000-20000 as segment 1, and dp=1, br=0 20000-30000 as segment 2, and dp=2, br=0 I've tried lots of different numbers but can't get it right. If anyone has worked on this or has any insights, any help would be greatly appreciated. Thanks very much.

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17-06-2009, 05:45 AM	#2
MattS00 Junior Member Join Date: Mar 2009 Location: Illinois Posts: 21	I'm really new to this, but I've seen something that may be similar, but I have not been able to figure out. I don't have a Evo 5/6/6.5, but I have a 2000 eclipse with a MH7203FA processor just like the e6.5 and I guess the AYC controller in other evos. On the xml for my rom the rom id is at address 1021a. I then use dasmh85.exe to open the rom. The memory range is from 0000 to ffff. If I type in the address of 021a the rom id is at that location, and there is no 1021a. What program do you use to open the rom to view it?

17-06-2009, 06:47 AM	#3
Ceddy Member Join Date: Apr 2009 Location: Pennsylvania Posts: 85	The H8s are offset +10000. So you need to add 0x10000 to your hex editor address. And to answer my own question above. The H8s are single chip mode(mode 7). There are three segments, but dp=0 for all of them. Also 10000-14000 is mirrored at 0-4000. I was confusing the low number addresses with a bad absolute address. Memory address 00000-03FFF = ROM 00000-03FFF (Seg 0) Memory address 14000-1FFFF = ROM 04000-0FFFF (Seg 1) Memory address 20000-2FFFF = ROM 10000-1FFFF (Seg 2) RAM EE80-FE7F REGS FE80-FFFF 4000-EE7F is Unused

17-06-2009, 07:42 AM	#4
MattS00 Junior Member Join Date: Mar 2009 Location: Illinois Posts: 21	What program do you use to open the rom? I think I'm really over my head here. I'm only catching bits and pieces of what I read. Is this what you are talking about?