DkTronics CPM

CPM+ with Memory expansions

CP/M+ already supports the Dk'Tronics RAM expansion but the CP/M+ on the system discs doesn't run on the CPC464/664 because it uses firmware v1.1 calls. Dk'Tronics provide patches to allow it to run on the 464/664.

One version is run as follows:

RUN"BANK

Press RETURN at the prompt. Then:

|EMULATE
|CPM

The disc boots, executes PATCH from PROFILE.SUB and is then ready to use.

The other version doesn't require BANK. You only need to type:

|CPM

CPM+ with Silicon Disk

The Silicon Disk rom has a command "|SETCPMPLUS" which patches the Amstrad CP/M with support for the Silicon disk. The resulting EMS file is called CPM3SEMI.EMS.

CPM2.2 with Memory Expansions

Dk'tronics Bank Switch software comes with NEWCPM.COM CP/M program which installs a 61K TPA CPM2.2 which uses the Dk'Tronics RAM. The documents describe how to make this CPM. They are repeated here and a pre-made dsk is linked to this page.

Creating the DkTronics 61K TPA CPM 2.2

Boot into CPM2.2 from system discs:

A>disckit2

Use disckit2 to format a vendor disc. This will become 'Dk'Tonics CPM Disk'.

A>BOOTGEN

This initialises the boot sector.

Source is: CPM 2.2 disk. Now insert 'Dk'tronics CPM Disk'.

A>SYSGEN

This puts CPM2.2 onto the disc. Source is CPM2.2 disk. Destination is 'Dk'Tronics CPM Disk'.

A>FILECOPY movcpm.com

This puts movcpm.com onto the disk. Source is 'CPM 2.2 system disc' disk. Destination is 'Dk'Tronics CPM Disk' disk.

A>FILECOPY save.com

This puts save.com onto the disk. Source is 'CPM 2.2 system disc' disk. Destination is 'Dk'Tronics CPM Disk' disk.

A>FILECOPY newcpm.com

This transfers Dk'Tronics newcpm.com. Source is 'Dk'Tronics bank switch software' disk. Destination is 'Dk'Tronics CPM Disk' disk.

A>FILECOPY oldcpm.com

This transfers Dk'Tronics oldcpm.com. Source is 'Dk'Tronics bank switch software' disk. Destination is 'Dk'Tronics CPM Disk' disk.

Now boot the Dk'Tronics CPM Disk.

A>MOVCPM 255 *

This configures a 63K CPM.

A>SAVE 34 NEWCPM.SYS

This saves a 63K CPM for Dk'Tronics CPM to use.

Your Dk'Tronics CPM is setup.

Technical

• 61K TPA is not active until NEWCPM.COM is run.
• 61K CPM is stored in "NEWCPM.SYS" and is loaded by NEWCPM.COM

NEWCPM.COM

• NEWCPM.COM is a normal COM file. It is loaded like a normal COM file. It resides in memory in bank 0 but configures a 61K CPM in bank 1 and transfers control to it. It remains in bank 0 and implements parts of the 61K CPM BIOS.
• NEWCPM.COM sets up a BIOS jumpblock in page C7 at &FC00. This calls into the resident NEWCPM.COM code in bank 0
• NEWCPM.SYS is first loaded to B00 in bank 0, it is later copied into bank 1 to it's correct location.

TPA upper address is &F300. BIOS jump is at &FC00. Code after &FC00 is part of the BIOS in bank 1.

OLDCPM.COM

• OLDCPM.COM is much simpler than NEWCPM.COM. It restores the dormant CPM in bank 0. If NEWCPM.COM was used it remains dormant in bank 1.

CPM 2.2 with Silicon Disk

The Silicon Disk has a command "|SETCPM" which patches CPM2.2 for the Silicon Disk.

Downloads

• File:Dkcpm.dsk - CPM2.2 configured for 61K TPA - This was made following instructions in the Bank software
• File:Dkplusbank.dsk - CPM3.0 with Dk'tronics PATCH (run BANK first) - This was made following instructions
• File:Dkplusnobank.dsk - CPM3.0 with Dk'tronics PATCH (BANK not required) - This was made following instructions