Colin MK II


Technical Specifications
The table below shows the as built specifications of Colin MKII, circa 1992.

Processor HD64180 - 6.144Mhz
Memory 128kB Static RAM
Firmware HBOS V1.81 - (8k EPROM)
Operating system CP/M 2.2
Video display Memory mapped monochrome display
- 80 chars x 24 lines
- Composite video output
Memory mapped colour Teletext display
- 40 chars x 24 lines
- UHF output (PAL), Composite video & TTL RGB & Sync
Keyboard 7 Bit parallel ASCII
- Carter Professional Model 756
Floppy Disk storage Dual 8" Floppy drives. SSSD
- 77 track (Shugart 801)
Single 5¼" Floppy drive. DSDD
- 40 track (Micro Peripherals)
Single 3½" Floppy drive. DSDD
- 80 track (NEC)
Printer output RS232
Serial interfaces RS232 port with full handshaking

Initial firmware
The operating system firmware for Colin MK II was in part, derived from the operating system which was running on Colin MK I.

Improvements and additions had been made to the original BOS, which was then re-named HBOS (Hitachi BOS).

In addition to improving the original firmware, the EPROM was expanded from 2kB to 8kB in order to include the provision of a BIOS section for running CP/M 2.2.