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Re: More fun with Freed Z80



mdj wrote:
On Feb 16, 4:10 am, Steven Hirsch <snhir...@gmail.com> wrote:
All,

I received my 512k SRAM chips yesterday and upgraded the board.   It now
provides a 391k on-board ramdisk when the RAMDISK.DVR is genned into the system.

I can also confirm that my ProPartition utility and driver works fine. I was
able to create a quick 4MB partition on my CFFA and am using that as the A:
disk currently (you cannot boot directly from the hard disk with this driver.
That will have to wait until I can blow the dust off the modified PCPI
operating system that boots from ProDOS).

Intersesting... What's the status of this? I've yet to put my board
together, but I do prefer the idea of running it from ProDOS

I'm busy trying to piece together what I did to make that work. It was done as proof-of-concept for the CardZ180 project and never really polished up. Instead of writing to the boot tracks of the disk, the setup program created a DRIVERS file and a relocated PCPICPM.SYS. You copy them to a ProDOS boot disk (using a disk transfer utility to bootstrap yourself) and startup from there. The PCPI 6502 BIOS basically runs as a ProDOS SYSTEM program and, once running, can use the filesystem services to better support transfer between CP/M and ProDOS. I have a utility called pdosxfer that's use to move things back and forth.

The transfer program for the CardZ180 would preserve time and date stamps between the two environments when the Z80 side was running an OS that supported them (Z-System and/or DateStamper). Not sure if that feature was ever working with the Applicard. There's enough similarity between them that a port would be possible, I'm sure.

It's been over 20 years since I've laid eyes on the code. Originally it used a home-spun patching program to modify a users operating system files. At this point in time, I'll just distribute the pre-patched code if I can get things working.

I have the USB interface and 20Mhz. crystal already.  The 20Mhz. Z80 and PLDs
should be here Monday.

It's tempting, but I'm worried that at 20Mhz, I might leave the II in
Z80 mode all the time ;-)

If you have an accelerator on the A2 side, it's even more impressive! This type of Z80 card can run just fine with accelerated 2e and 2GS systems.

Steve