Author Archives: aslak

EEPROM programmer improvements and… stripboard sucks

This Easter weekend I’ve been working on the EEPROM programmer again. The programmer PCB has been “in production” now for about a week, with a few weeks left.  In the meantime I thought I would brush up on my soldering “skills” and make the circuit up on stripboard.  This turned out to be a slightly crazy thing to do; stripboard… Read more »

Adventures with an ATTiny85

      1 Comment on Adventures with an ATTiny85

As a little diversion on the bumpy road to the 8bit world of the 6809, I’ve been playing about with some AVR ATTiny’s, specifically the ATTiny85. Mostly to see what they can do and to see if they could be used for interfacing peripherals to an 8bit MPU. These are amazing little beauties; 8Kbyte flash, a tiny amount of RAM,… Read more »

EEPROM programmer source code

      No Comments on EEPROM programmer source code

The software for the programmer is in two parts, the “firmware” that runs on the ATMEGA8, and a program intended to run on a Linux machine which sends a file to the ATMEGA8 which it then writes onto the EEPROM. Both bits of software are available on my github account.  This is not the nicest code I’ve written, but it… Read more »

EEPROM programmer circuit

      2 Comments on EEPROM programmer circuit

The circuit is relatively simple once the block diagram has been devised. For the serial port, a USB lead meant for interfacing to the RS232 port on a mobile phone was used instead of something more conventional like a MAX232 level shifter. Something like this from ebay would also work. On the ATMEGA8, the whole of PORTB is used for the… Read more »

Return to the past. 8 bits are enough for anyone.

As a computer user/programmer for the past 20 years, I’ve always had one ambition: to build a real working computer from components.  No, not a PC (which anyone can do), but a computer from the ground up. My inspiration comes from various sources, including using a 6502-based education board at college and being amazed at the general simplicity of the… Read more »

WLAN phone operated tank with webcam – hardware

Intro A few years ago I bought a “bifferboard“.  This amazing little computer is about the size of a box of matches, and has the computing power of, well, about a Pentium 100.  But it’s good enough to run a headless Linux environment.  After I bought my bifferboard I was impressed with it, but couldn’t really come up with anything… Read more »