August 2018 archive

Building TZXDuino

To load programs on the AZ Spectrum you need a cassette player…or so I thought.   Came across TZXDuino which lets you play files from the SD card using an Arduino and a amplifier.   Rigged this up in a morning and it works beautifully. I updated the code to use a LCD 16×2 without I2C. …

Continue reading

Programming the 28C256

Not having a programmer for this chip I decided to  use my Arduino. After trying out various projects on the internet I eventually came across TommyPROM which uses 74LS164 serial to parallel shift registers. Wired up to my Arduino Uno, fired up TerraTerm  and uploaded the diagnostic ROM to the 28C256. The 28C256 is a reflashable  …

Continue reading

Spectrum RGB DIN to SCART Pinouts

After looking on the internet there seems to be a lot of confusing information on the pinouts for building a DIN to SCART cable. I’ve looked through the harlequin schematic and SCART pinouts and it should be as follows: Spectrum Harlequin RGB DIN to SCART DIN  ———–> SCART PIN – SCART Function Pin 1 ———–> …

Continue reading