It seems the repairs to my venerable Epson MX-80 F/T III dot matrix printer did actually work because it’s now printing again! What’s more, it’s printing via the prototype of my DottyMatrix serial to Centronics parallel interface. Time for a quick recap. The DottyMatrix is based around an AVR ATMEGA328PB microcontroller. It takes input on a TTL-level serial connection and… Read more »
My old, beloved Epson MX-80 F/T III dot matrix printer is back in the land of the living. For now. As you can see from some of my earlier posts, I’m designing a serial-to-parallel interface with Centronics compatible DB25 connector so that I can print to my Epson from anything with a TTL serial port, such as a Raspberry Pi…. Read more »
In designing my DottyMatrix serial-to-parallel printer interface, I had to decide how it would handle the incoming data stream. The purpose of the DottyMatrix is to connect my venerable Epson MX-80 F/T III dot matrix printer to (probably) a Raspberry Pi so that I can print out text files, such as program listings. Obviously, it would be good if it… Read more »
The Centronics interface seemed such an intrinsic part of a computer’s architecture that, to those of us whose computing coming-of-age was in the 1970s or 1980s, it seemed unimaginable that it would all but disappear. Who knew that serial interfaces would one day reign supreme? There’s something still very satisfying about hooking up a parallel connection, with fat cables and… Read more »
One of the issues with the Serial Peripheral Interface (SPI) bus, as many people have noted, is that it requires one Slave Select (SS) line – which means one GPIO pin on your microcontroller – for each device on the bus. That’s in addition to the three main bus lines – MOSI, MISO and SCK. This might be difficult on… Read more »