Mc-2g-102

Z80 - mc-2g-1024

• The specifications are:
  • New ROM monitor with multi-boot capability, Format, Getsys and Putsys tools and debug capabilities. No BASIC in ROM.
  • SD-HC capable card controller.
  • Multi volume disk system, which currently supports upto 254 8MB disk volumes (which uses 2GB+ on the SD-card). All these volumes can be loaded with a separate OS bootimage.
  • OSes configured with 3 drives: A:, B: and C:. A: is the system drive (holding the volume booted from) while B: and C: can be assigned and re-assigned one of the remaining volumes. Also a RAM disk for CP/M 2 and CP/M 3
• Y2k compatible system clock (date and time) for all OSes.
• mc-2g-1024 on retrobrew site
• Supports:
  • Dos+ 2.5
  • CP/M 2.2
  • CP/M 3.1
  • ZSDOS 1.1 / ZCPR2
  • ZPM3 /ZCCP
  • NASCOM “ROM” BASIC 4.7

RAMDISK

• The CP/M2 and CP/M3 variants support a ramdisk, either 384kB (in s 512k system) or 896 kB (using 1024 kB SRAM).
  • This size is adjusted by the BIOS.
  • The contents, once initialized with RDINIT.COM, persists as long as the board remains powered, with one caviat: MP/M uses this memory too, so booting MP/M overwrites part of the memory used for the ramdisk.
• MP/M does not (yet) support a ramdisk.

S1 - CP/M 2.2 - Dos+ 2.5 - CCP+ Ver 2.2

• This is an unpatched implementation by C.B. Falconer's Dos+ version 2.5.
  • Please read the documentation to switch on the optional features.
• Because this OS treats console input differently (it checks for user breaks after each character it outputs) the original DOWNLOAD.COM no longer works.
  • It was modified to use direct BIOS I/O to circumvent the above behaviour, but because after every file the command prompt is displayed some characters are still lost.
  • This is circumvented by padding the input file with enough spaces to make up for the lost characters.
  • This version of DOWNLOAD.COM also works under CP/M 2.2 and CP/M 3.
    • A way to work around this is to just download all the files you want under CP/M 2.2 to the target disk mounted as B: or C:
• Dos+ implements a search path which is initialized by the command STARTUP.COM.
  • STARTUP.COM is automatically run when the system is first booted.
  • STARTUP.COM can be any .COM command you like, as long as the name does not change.
• Mounting drives is done with the MOUNT.COM tool.

S2 - CP/M 2.2

• This OS is as was provided by Grant Searle.
  • It uses a new BIOS, providing mountable volumes, a Ramdisk and a clock.
  • All Grant's tools work as intended, in particular the original DOWNLOAD.COM.
• The start address for the initial download of "DOWNLOAD.COM" (backdoor startup) from the provided .HEX file has changed to FFFB.

S3 - CP/M V3.0

S4 - MP/M II V2.1

• MP/M also boots a loader, which in turn loads MPM.sys from the chosen volume.
• The XIOS also supports mountable diskvolumes, however these can be asigned only during a cold boot.
  • The mounting mechanism is similar to the CPM-2 version, but an easy vector to the mount table is not implemented.
  • Although this is doable, changing volumes in a multi-user environment should be avoided.
• The BIOS supports 4 consoles.
  • Using the GENSYS.COM tool this number can be changed.
  • It is OK to connect less consoles than configured, but this will use system resources (memory and processor time).
• MP/M XIOS is currently a vanilla implementation straight from Digital's documentation.

S5 - Z80 BASIC

S6 - CP/M 2.20 - ZSDOS v1.1

• ZSDOS is a CP/M 2.2 variant, but it requires a modified BIOS.
  • The changes include a modified time and date routine as well as increased bufferspace for the various ZCPR features.** Also a "HighMemory" buffer for the time/date driver and timestamper routine is provided. (see sourcecode for details).
  • The included LDTIM.COM routine loads the driver to the correct location.

S7 - CP/M V3.0 - ZPM3 / ZCCP

• ZPM3 is CP/M-3 variant, which uses the same BIOS code as CP/M-3.
  • A rudimentary NAMES.NDR file was included to jump-start the "named directory" feature.
  • A TCAP.Z3T for use with a DEC VT-100 terminal is also present.
    • A working TCAP is needed for many of the ZPM3/ZCCP user programs.

S9 -

S10 -

S11 -