Breathing life into an old LCD


Out of the depths of a junk drawer, [Alex]‘s friend pulled out an old monochrome LCD display. This is an older low-resolution display from ancient electronics that unfortunately doesn’t have its own controller chip. No worries, though, because with the help of an FPGA [Alex] figured out how to drive this display.

On the back of this display are eight Hitachi LCD drivers, six column shifters and two row shifters, allowing the LCD to display a 256×128 pixel image. Without an LCD controller, though, [Alex] couldn’t just send a static image to the LCD. Instead, he had to continuously refresh the display just like a VGA monitor.

With the help of a 1500-page PDF titled Hitachi LCD Controller/Driver LSI Data Book, [Alex] was able to dump pixels into the ICs on the display with the help of a Papilio One FPGA board. A lot of work just to display the beautiful [Lena], but she wouldn’t have it any other way.

A hardware random number generator for your FPGA

[Zach] sent in a project he’s been working on that brings hardware random number generators to common hardware you might have lying around. It’s called Whirlyfly and it turns an FPGA dev board into a hardware random number capable of outputting random bits over a USB connection at 3 Mbps.

Previously, the whirlygig ran on a custom CPLD that interfaced to a *nix box and provided high quality random numbers via /dev/hw_random. [Zach]‘s efforts takes the core of the whirlygig and ports it to the very popular and inexpensive Papilio One FPGA dev board.

As for what [Zach] can do with his random number generator, it’s extremely easy to write a Monte Carlo experiment to approximate the value of π with a better accuracy than [Ptolemy] was able to muster 1900 years ago. There’s also the aspect of encryption, and – why you would do this we have no idea – making an uncompressable file is also possible.

NTSC video out with the Papilio One


[Ben Leperchey] is working on building a Sega Master System clone using the Papilio One FPGA board, and although his ultimate goal has yet to be reached, he’s bringing some great stuff to the table in the meantime.

One component that is necessary for any sort of game system clone is NTSC/PAL video output, naturally. Since no one had constructed a TV output “Wing” (The Papilio One’s version of a shield or breakout board), [Ben] went and did it on his own. Using only 14 resistors and a low-pass audio filter, he was able to get the video output he was looking for with relatively little trouble. His VHDL code running on the Papilio does all the hard work of creating the video signal, while the wing he designed mostly handles the connectivity.

This is one of the first few projects/components we’ve seen come out of the Papilio camp, and it looks like things are off to a good start. We can’t wait to see the Master System implementation once it has been wrapped up!

Continue reading to see a quick video demonstration of the Papilio One and [Ben’s] TV output wing.

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