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Any way to use hex/rom files on a Epson PX-8?

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theancientone

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I have a barebone PX8 that came just with one slot with extended CPM commands; there is one slot free which is where Basic was supposed to be I guess. As I do not have an Eprom writer and I do not plan to swap roms to switch applications, I was wondering what alternatives I have.
I found all the rom files in hex/rom format on the main PX8 site; can I make a larger rom that include all of them, as a rom will look like a disk to the CPM OS, so it won't really matter to it? Or can I convert those in binary files I can sync via serial from my computer, and save them locally on the storage on the machine?

My concern with roms is that they can break the plastic on the computer by swapping them; which is unfortunate if that happens. What are my options here?
 
Thanks, this looks interesting; is there any way to use the actual files without use the hardware? I can connect the computer to my other computer via serial, so I can copy the software maybe?
 
I don't think this is what you want, but in case it helps, I believe that the PX-8 is the international version of the HC-80. There is an emulator for the HC-80 here, though I don't know how complete it is. (I've had good luck with the PC-8001 emulator from that project, though, running it on LInux under Wine. Getting the ROM formats right can be tricky, however, though reading the source code can help with that.)
 
Thanks; so I would get the emulator, load these HEX rom files in it and then copy the software off of it? Is the emulator able to save on my local disk these files? Or should I connect the PX-8 to the computer running the emulator via serial port and transfer files that way?
I assume there is nothing that open these HEX files as if they were IMG files?
 
theancientone said:
Thanks; so I would get the emulator, load these HEX rom files in it and then copy the software off of it? Is the emulator able to save on my local disk these files? Or should I connect the PX-8 to the computer running the emulator via serial port and transfer files that way?
Click to expand...
Oh, no, the emulator doesn't help you at all for getting that ROM code on to your real system. (Unless I'm missing something super-clever.) It would just let you test it more easily.

theancientone said:
I assume there is nothing that open these HEX files as if they were IMG files?
Click to expand...
I'm not sure exactly what formats these are, but there are conversion tools all over the place to convert between various formats. HEX files are often Intel Hex format, and IMG sounds as if it's straight binary, so converting between those two is easy.

As far as getting ROMs for your real machine, whoever burns those for you can no doubt accept either format.

(I'd love to have a closer look at this in person, as I've been wanting to get an "upgrade" from my Epson HC-20s for a while, but I just had a look on Yahoo Auctions and HC-80s have both become rare and gone way up in price in the last few years. :-( )
 
Hi Theancientone,

These ROM files, both hex and bin are images with a 32kbyte file system. AFAIK, there is no program or script to copy the files in the image to a PC directory. It is not hard to make, it is just not very often needed.
Your options are a FILINK transfer (program on the Util ROM), but that requires a cable connected to the RS-232c port. A more interesting option is a disk emulator, that gives you drives D:, E:, F: and G: all on one SD-card. A custom program on the PC can copy files from and to the disk images on the SD-card. But it also requires a cable. The same as for the FILINK option, but it uses the SERIAL port.
An example I know quite well is https://hackaday.io/project/193978-pfbdk-epsp-floppy-drive-emulator. But you have to make it yourself; unless you can find someone else to do it for you.

Greetings,
Fred Jan
 
The roms are connected to the address space, and normally are not relocatable due to using absolute addressing in the machine code.
 
The ROMs the original author referred to are the 'B:' and 'C:' ROMs of the PX-8. These are 'file-system-ROMs', containing a directory and files, just like a 32kByte sized floppy. Technically they are a switchable part of the 6801 co-processor memory map*. The PX-8 runs CP/M, so all program files start at 0100h in the CP/M TPA.

*) The PX-4 is different, there the ROMs are switchable part of the Z80 memory map, between 6000h and DFFFh. The P-type ROMs use this feature by running programs directly from ROM. PX-4 BASIC is the prime example. This makes this BASIC definitely not a CP/M program.

Greetings,
Fred Jan
 
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