Author Archives: monsonite

About monsonite

mostly human

Exploring DIY CPUs

In the last couple of posts I described how I have used a TI MSP430 Launchpad to emulate the 1949 Cambridge University EDSAC machine. This opens up the possibility of using a similar scheme to emulate virtually any DIY cpu, … Continue reading

Posted in Uncategorized | 2 Comments

When you are strapped for resources……

In early August, I spent a few days on the Greek peninsula of Kassandra, to the south of Thessaloniki. In order to keep my mind stimulated and an excuse to keep out of the full-on daytime sun, I took along … Continue reading

Posted in Uncategorized | Leave a comment

Computer Science from the Ground Up.

  Imagine that you have just taken a 1 term course in Electronic Engineering and Computer Science and you are now facing the end of term exam: Part 1 – Digital Logic. 1a. Using transistors, diodes and resistors, show how … Continue reading

Posted in Uncategorized | 2 Comments

A simulator for “mini-EDSAC” coded in C

Back in May, I entered into correspondence with Bill Purvis, who is involved with the recreation of EDSAC at The National Museum of Computing, at Bletchley Park. Bill has created a simplified model of EDSAC, which runs on a 1K … Continue reading

Posted in Uncategorized | Leave a comment

SIMPL on EDSAC

SIMPL on EDSAC When you start coding on a new processor architecture, you always have the initial problem of how to get some sort of a bootloader into memory, to allow you to then load your application program into memory. … Continue reading

Posted in Uncategorized | Leave a comment

Opening up EDSAC

EDSAC was the first of the Cambridge University computers, brought up in 1949 and intended for real scientific and mathematical work. This year, there is considerable revival of interest in EDSAC – as the National Museum of Computing at Bletchley … Continue reading

Posted in Uncategorized | Leave a comment

SIMPL Gets Simpler

This week I have been working on my tiny, Forth-like language SIMPL. ┬áin a few hours of spare time I have managed to optimise some of the routines and get the code size down from around 900 bytes to just … Continue reading

Posted in Uncategorized | Leave a comment