HP 48GX ROM Dump

[Christoph Giesselink]

(07-21-2022 04:26 AM)Richard Garner Wrote:  Copy the ROM to the folder that Emu48 is installed in. You will need to rename the ROM to rom.48g. When you run the program it will ask you to select a KML Script. It should have one already chosen as defalt. Click on ok and it should bring up the emukator. The select a KML Script came be turned off later if you wish. Additional Skins with KML Scripts can be fpound at hpcalc.org.

When you just rename the gxrom-r to rom.48g and start a HP48GX self test you will get an IROM 05E61 FAIL 00002 error.

This is a problem of all HP48 ROM images and the HP38G image at hpcalc.org. When you call the convert.exe utility from the Emu48 package with one file argument to verify the ROM image, you will get an OK for all ROM images. Basically, the topic "HP48 emulation" is quite very old, also the methods of creating a ROM image. So there're exists many ROM formats for different purposes. The convert.exe utility was designed to analyse the HP48 ROM input format, convert the input file into an internal format ROM and verify the internal format for correct CRC's.

In the case of the gxrom-r file, the ROM at the mapped I/O register area still contain the I/O memory data from the upload which is reponsible for the IROM 05E61 fail. Using the convert.exe utility with a 2nd file argument, convert.exe creates an unpacked ROM image file in a suitable Emu48 format.

convert.exe gxrom-r ROM.48G

The unpacked ROM format is the ROM format Emu48 is internally using and in the case of a 48G-series ROM it has a size of 1024KB. Later versions of Emu48 also accepted a packed ROM format with a 48g-series ROM size of 512KB.

To generate such a file from gxrom-r you may call

convert.exe gxrom-r ROM.TMP
emu2rom.exe ROM.TMP ROM.48G

The resulting file ROM.48G is very similar to the gxrom-r file, only the I/O register area are is filled with Zeros. This ROM file don't cause a selftest error.

A forthcoming convert.exe version in the Emu48 v1.65 distribution allows to create a packed ROM image file directly:

convert.exe -p gxrom-r ROM.48G

In the case of the gxrom-p ROM file from

HP 48GX Revision P ROM
https://www.hpcalc.org/details/4369

the gxrom-p file will not work after renaming to ROM.48G because in this file the nibbles in a byte are swapped and so gxrom-p isn't a valid packed ROM image file for Emu48.

Using

convert.exe gxrom-p ROM.TMP
emu2rom.exe ROM.TMP ROM.48G

create a valid packed revision P G-series ROM image.

The file emu2rom.exe is part of my https://hp.giesselink.com/Pcuti/FILETOOL.ZIP package.