Logic and EEPROMs bring VGA to Life, Sans Microcontroller

For whatever reason, the Video Graphics Array standard seems to attract a lot of hardware hacks. Most of them tend to center around tricking a microcontroller into generating the signals needed to send images to a VGA monitor. We love those hacks, but this one takes a different tack – …read more

Continue reading Logic and EEPROMs bring VGA to Life, Sans Microcontroller

Logic and EEPROMs bring VGA to Life, Sans Microcontroller

For whatever reason, the Video Graphics Array standard seems to attract a lot of hardware hacks. Most of them tend to center around tricking a microcontroller into generating the signals needed to send images to a VGA monitor. We love those hacks, but this one takes a different tack – …read more

Continue reading Logic and EEPROMs bring VGA to Life, Sans Microcontroller

A TTL CPU, Minimising Its Chip Count

By now we should all be used to the astonishing variety of CPUs that have come our way created from discrete logic chips. We’ve seen everything from the familiar Von Neumann architectures to RISC and ever transport-triggered architecture done in 74 TTL derivatives, and fresh designs remain a popular project …read more

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A 6502 Computer, With Acres Of Breadboard And Dozens Of Chips

Imagine you’re time-warped back to 1979 and tasked with constructing a personal computer. Could you do it? [RadicalBrad] thinks he can, and his 6502-based “Super VIC” build looks like it’s off to a great retrocomputing start.

Most emulations of old hardware these days go the FPGA route, and while we …read more

Continue reading A 6502 Computer, With Acres Of Breadboard And Dozens Of Chips

The 7400 Quad 2-Input NAND Gate, A Neglected Survivor From A Pre-Microprocessor World

There are a range of integrated circuits that most of us would regard as definitive examples of their type, devices which became the go-to for a particular function and which have entered our collective consciousness as electronics enthusiasts. They have been in production since the early days of consumer integrated circuits, remaining in use because of a comprehensive understanding of their characteristics among engineers, and the job they do well.

You can probably name the ones I’m going to rattle off here, the µA741 op-amp designed by David Fullagar for Fairchild in 1968, the NE555 timer from Hans Camenzind for …read more

Continue reading The 7400 Quad 2-Input NAND Gate, A Neglected Survivor From A Pre-Microprocessor World

Behold The WT-220: A ‘Clever’ VT-220 Terminal

[John Whittington] failed to win a bid for an old VT-220 serial terminal on eBay, so he decided to make his own version and improve it along the way. The result is the Whitterm-220 (or WT-220) which has at its core a Raspberry Pi and is therefore capable of more than just acting as a ‘dumb’ serial terminal.

The enclosure is made from stacked panels of laser-cut plywood with an acrylic plate on the back for labels and connectors, where [John] worked paint into the label engravings before peeling off the acrylic’s protective film. By applying paint after laser-engraving but …read more

Continue reading Behold The WT-220: A ‘Clever’ VT-220 Terminal

Behold The WT-220: A ‘Clever’ VT-220 Terminal

[John Whittington] failed to win a bid for an old VT-220 serial terminal on eBay, so he decided to make his own version and improve it along the way. The result is the Whitterm-220 (or WT-220) which has at its core a Raspberry Pi and is therefore capable of more than just acting as a ‘dumb’ serial terminal.

The enclosure is made from stacked panels of laser-cut plywood with an acrylic plate on the back for labels and connectors, where [John] worked paint into the label engravings before peeling off the acrylic’s protective film. By applying paint after laser-engraving but …read more

Continue reading Behold The WT-220: A ‘Clever’ VT-220 Terminal