When I was a Young Chap

8 April 2001

I've been a geek for many years. This is the remains of my first computer which I built when I was 12, and is circa 1977/78.

The version here has 1k RAM, 512 bytes PROM.

It's based on a General Instrument LP8000. In those days, because of the large (48 byte) register set, there wasn't enough space on the chip for a program counter too: so you needed an LP1000 chip to do that work.

No printed circuit board: all hand wired small scale integration 74 series TTL.

Hex keypad, 16 LEDs, and four toggle switches. No UART. No non volatile storage except a boot hex monitor.

Unfortunately my construction techniques haven't improved much since then.

Mail Howard, G6LVB