Dorptrum / MENSCH Computer Card

CPU card based around the 16-bit MENSCH Computer.


This is a CPU card for the Dorptrum. It uses the WDC65C265 based MENSCH breakout board. The MENSCH provides many useful features like an internal monitor ROM, 512 bytes of onboard SRAM ($0000-$01FF), I/O chip select, 4MHz clock, two tone generators, and four UARTs. This is the first card I have made. It is going to be used to develop the Dorptrum until the computer is far enough along that I can switch to discrete cards for each component. Due to poor design on WDC's part, a wire is soldered directly to the I/O chip select pin because the MENSCH has the chip select pins connected to LEDs instead of to pins.

The WDC65C265 contains a WDC65C816 8/16-bit CPU which is backwards compatible with the 6502 ISA.