BMOW is a Custom CPU Design Like your PC’s Pentium, but much simpler Closest cousin is the MOS 6502 used in the Apple II, C-64, and Atari VCS =

BMOW is a Custom CPU Design Three 8-bit data registers 24-bit address size 64 KB segments 12 addressing modes Microcoded design From 1 to 16 clocks per instruction

BMOW is Hand-Made Built from 1970’s and 80’s era electronics 50 simple chips are connected to form the CPU –AND gates, counters, multiplexers, registers –Simple GAL programmable logic

BMOW is Hand-Made Chips connect by wires under the system board Wires are hand-wrapped around the pins About 1250 wires total, 2500 wraps

BMOW is a Complete Computer PS/2 Keyboard input Text LCD display Optional USB connection to PC VGA video output Three-voice audio

BMOW Video System Custom video circuitry 512 x 480 max resolution 256 simultaneous colors 16 different video modes Video mode can change on every scan line Mixed text and graphics modes Standard VGA output

BMOW Software Tools Bootloader Simulator and debugger Microcode assembler Program assembler

BMOW Specs Comparison NameYearCPU Clock Speed Data Size Address Size MemoryI/OSoundMax Res. Max Colors Apple II1977 MOS MHz81648 KB cassette, floppy disk 1 software voice 280 x Atari MOS MHz81648 KB cassette, floppy disk 4 hardware voices 320 x Commodore MOS MHz81664 KB cassette, floppy disk 3 hardware voices 320 x IBM PC1981 Intel MHz8 / KB cassette, floppy disk 1 software voice 640 x BMOW2009custom2 MHz KB serial over USB 3 hardware voices 512 x

BMOW Project Summary 1½ years to build 2500 hand wire wraps $500+ worth of parts Why? I don’t know.