HEPAX ROM XROM Numbers

[Marksail2]

I need the ability to change the XROM numbers of the ROM images coming out of the HEPAX module. Currently the ROMs generated are XROM 11 and 12 which once converted to MOD files may conflict with other installed MODs. I know there is a way using HEXEDIT before generating the ROMs however manipulating them is not really an option. Is there software out there that allows me to edit the XROM numbers either in the ROMs themselves or in the MOD file directly?

Any help would be appreciated!

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[rprosperi]

(05-22-2021 11:32 AM)Marksail2 Wrote:  I need the ability to change the XROM numbers of the ROM images coming out of the HEPAX module. Currently the ROMs generated are XROM 11 and 12 which once converted to MOD files may conflict with other installed MODs. I know there is a way using HEXEDIT before generating the ROMs however manipulating them is not really an option. Is there software out there that allows me to edit the XROM numbers either in the ROMs themselves or in the MOD file directly?

Any help would be appreciated!

/\/\

I think you can use a hex editor on the PC to modify the ROM ID byte in the .mod file before loading, however I believe there are (unknown to me) events where the HEPAX module will restore the original ID values.

Hopefully Angel, Diego, Sylvain, etc. knows what events trigger the changes.

But easy enough to try, just hack a copy of the .mod file, install it and check the new IDs.

[MeindertKuipers]

Best to do the editing in the .ROM file on a PC with a hex editor as this is simply the first word in the file. Doing this in the .MOD file is not trivial due to the semi-compressed file format and the presence of the header with meta-data.
Editing the ROM file is on my list of nice things to have in the RomHandler software ...

[Marksail2]

I have read that using HEXEDIT within the emulator can change the header information within the ROMs however its tricky and cumbersome. Looking for a much more straight foward way. The problem herein lies that ROM's generated from HEPAX RAM contain XROMs 11 and 12 thus can not reside side by side with an existing HEXPAX installation. That is after being "burned" into MOD file format. You can only have one OR the other thus the need to change the XROMs of the incoming MOD file.

[Ángel Martin]

it's as easy as changing the very first word at the beginning of the HEPAX:RAM page, at address 0xp000 where p is the page number from 8 to F

XEQ "HEXEDIT"
ADR: _ _ _ _ p000

then enter the xrom id# you want at that address, also in Hex.

[Marksail2]

I have to admit I am not conversant with editing hex values. I have two pages that would need to be changed. Say for example I want to change the 11 value to 16 and the 12 value to 17 I don't have a clue as to where I would start. I can invoke the HEXEDIT no problem but finding what value to change (and to what) is my worry. It seems easy enough just don't know what to look for

I appreciate the time you are taking on this for me.

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[rprosperi]

Angel's guidance is exactly what you need to follow.

For example, if you want to change ROM ID 11 in the first page of HRAM (which by default is page-8) to 16, you would the following:

[XEQ] "HEXEDIT"

fill in the address to edit, in this case "8000", and the editor will display

8000 00B _ _ _

Which means at address 8000, the current value is B (which is 11 in decimal) and is prompting you to fill in the desired value of 010 (which is 16 in decimal) so you enter

0 1 0

HEXEDIT will write that value (010) at that address, then advance to the next address and display

8001 xyz _ _ _ (where xyz is the value stored there and will vary) and waiting for you to enter a new value, but there is no need to change any more, so just press [ON] to exit HEXEDIT (but will also turn the 41 off, which is normal).

And repeat the process for the 2nd block, which is likely at address 9000, where you will change the "00C" to "011" (which is changing from 12 to 17 in decimal).

[Marksail2]

Thank you to all that responded! An example is exactly what I needed. I was vaguely familiar that I was looking at 8000, 9000 and using a Hex to Decimal converter I could get the same as you provided. I will give it a try and let you know how it turns out. The trick will be to have burned modules reside in the same emulation as HEPAX (and each other).

FYI : I am using i41CX+ for my emulator and am thrilled to be able to get my programs operating correctly via the...
HEPAX --> ROM --> MOD route. I have spent over a year perfecting my programs for just such a transition!

I will keep you posted

Regards,
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