New PAL-II and (yet another) CP/M-65 port
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Eduardo Casino
May 20, 2025, 8:15:22 AMMay 20
to PAL 6502 computer
Hi,
- Place the CPM-BOOT.DSK image at the root of a FAT32 formatted SD card and create an SD.CFG file with this content:
0:CPM-BOOT.DSK
- Start the KIM-1 in TTY mode, load the bootsdshield.pap loader program into 0x0200 and execute it.
- For the PAL-2, you can place the `bootsdshield-kimrom.bin` bootloader into the free space of the KIM-1 rom, starting at 0x1AA0 (or 0x2A0 relative to the KIM-1 rom). This romable loader has two entry points:
- 0x1AA0 is for cold start, that is, you can point the 6502 reset vector to 0x1AA0 if you want to start CP/M-65 at reset. In this case, the TTY is initialized to 9600 bauds, so make sure that your terminal is configured to that speed.
- 0x1AB2 is for booting from the KIM monitor
- At least a 32KB (56KB recommended) RAM from 0x2000 is required, as well as RAM filling the 0x0400-0x13ff memory hole. The BIOS assumes that at least the required RAM is installed, and checks for extra RAM above 0xA000.
- Up to 4 disks are supported.
- Only TTY interface for now, no SCREEN driver.
- An Image Manipulation Utility, IMU.COM, is included. It allows mounting and unmounting disk images and, with the latest SD Shield firmware, even copy, rename, delete or create new ones. Do a "TYPE IMU.TXT" to see the help page.
A new PAL-II is born!
It turned out to be even more beautiful than expected, I love this form factor!
You'll see and SD Shield attached to the expansion board using this little adapter:
Which let me run a new CP/M-65 port, this time using Corsham's SD Shield (either the original, my clone or even Retrospy's Pico based one)
This port uses the block access functions of the SD Shield that, to my knowledge, were only used with the 6800 based Corsham's boards, not with the KIM. I've also updated the shield's firmware to fix a few bugs and add new functionality.
To run this port:
- Download the disk image and boot programs from https://github.com/eduardocasino/cpm65/releases/tag/kim-1-sdshield
(It is not yet merged into David's repo)
- Place the CPM-BOOT.DSK image at the root of a FAT32 formatted SD card and create an SD.CFG file with this content:
0:CPM-BOOT.DSK
- Start the KIM-1 in TTY mode, load the bootsdshield.pap loader program into 0x0200 and execute it.
- For the PAL-2, you can place the `bootsdshield-kimrom.bin` bootloader into the free space of the KIM-1 rom, starting at 0x1AA0 (or 0x2A0 relative to the KIM-1 rom). This romable loader has two entry points:
- 0x1AA0 is for cold start, that is, you can point the 6502 reset vector to 0x1AA0 if you want to start CP/M-65 at reset. In this case, the TTY is initialized to 9600 bauds, so make sure that your terminal is configured to that speed.
- 0x1AB2 is for booting from the KIM monitor
- At least a 32KB (56KB recommended) RAM from 0x2000 is required, as well as RAM filling the 0x0400-0x13ff memory hole. The BIOS assumes that at least the required RAM is installed, and checks for extra RAM above 0xA000.
- Up to 4 disks are supported.
- Only TTY interface for now, no SCREEN driver.
- An Image Manipulation Utility, IMU.COM, is included. It allows mounting and unmounting disk images and, with the latest SD Shield firmware, even copy, rename, delete or create new ones. Do a "TYPE IMU.TXT" to see the help page.
Enjoy!
Hans Otten
May 20, 2025, 10:33:40 AMMay 20
to PAL 6502 computer
Congrats! Another PAL-2 (or PAL-II) with a usable operating system!
Hans
GN Liu
May 23, 2025, 11:19:39 PMMay 23
to PAL 6502 computer
Nice sharing!!!!
Thank you~~
Liu
Kurt Pieper
May 24, 2025, 5:52:20 AMMay 24
to PAL 6502 computer
Hello,
very nice board, I like it.
I prefer the Z80 and Z180 systems with CPM.
My favorite Z80 is the Kaypro 4/84 (converted Gotek with SD).
The original parts are still available, though.
I once had a C64 and C128 with a Z80 card.
I hope you enjoy the PAL-2 and CPM.
Kurt
very nice board, I like it.
I prefer the Z80 and Z180 systems with CPM.
My favorite Z80 is the Kaypro 4/84 (converted Gotek with SD).
The original parts are still available, though.
I once had a C64 and C128 with a Z80 card.
I hope you enjoy the PAL-2 and CPM.
Kurt
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