HP-71 Compu-LS module

[Dave Frederickson]

Hi Tom,

Hmmm. Christoph makes some good points.

I don't think the checksums are a critical issue as I believe the only thing that looks at them is the Service ROM, and a brain cramp made me think that ILvlif worked on the PC's drive.

The preferred method for dumping ROM's is either a PIL-Box or RS-232 interface. In lieu of those, ROMCOPY could still be used or the raw data could be dumped to a data file on the 9114. We're still faced with the issue of how to get the data into the PC.

There are a couple of utilities on the 9845 Project website that come in handy, specifically HPDir and Fdio. These will allow you to read/write LIF discs and images, but the floppy disc controller in your PC needs to be capable of low-level access. You can test your FDC using Dave Dunfield's TestFDC. Your FDC needs to pass the Double-Density test at 250kbps.

Then the data file dump can be converted to binary and along with a few tricks, loaded into Emu71 where the protection can be removed.

This sounds like a lot of work, and it is without a PIL-Box or FRAM71. If you like, I can offer to convert the EPROM.

Regards, Dave