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NoVRAM / HEPAX MCODE Question - Printable Version

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NoVRAM / HEPAX MCODE Question - Jeff Davis - 12-04-2010

Is there any specific procedure to allocate one of the HEPAX RAM pages as a ROM image? I would like to build a ROM image using the HEXEDIT program. If the HEPAX resides in 8-B pages would "B" be the page to allocate? Or is this even possible? I am assuming you could break the link in order to isolate this 4k block.
Please let me know.


Re: NoVRAM / HEPAX MCODE Question - Geir Isene - 12-05-2010

Take a look at the ram2rom feature (files in the Clonix package)


Re: NoVRAM / HEPAX MCODE Question - Frido Bohn - 12-06-2010

Hi Jeff,



It is possible to allocate HEPAX memory for other purposes, such as for ROM-creation.

Basically, you have to change the word at address xFF3 to 300h using HEXEDIT, were x denotes one of the pages 8–B. Then, addresses xFE7 and xFE8 have to be 000h. A detailed description can be found in the HEPAX manual Vol. 1, p. 63.

A neat example how to program a user-developed ROM can be found in the HEPAX manual Vol. 2, p. 153.



What Geir described above is the way how to copy the programmed ROM into Page F via ram2rom into the Nov64 system where Page F usually must be flashed, I believe. Thus, it would be the next step after you did your ROM programming.



Best regards

Frido