PDP-11/45: VT52

Spent some time reviving a VT52 that I intend to use with the PDP-11. This was a pretty nice eBay find. There was some oxidation and flakiness with the connectors to the chargen ROM daughter card (I remember this being typical of VT52s even back in the day). A little more difficult to track down were some flaky solder joints around the clock chip. But, everything else seems to be in pretty good shape and its working well now! Here it is hooked up to a Linux VM on my macbook, compiling some LSST code to generate some output as a test drive:

Man, seeing that funky font again, with its non-descending-descenders, is really great! Surprisingly, it doesn't seem to be available in digital format anywhere, unlike the later VT100 fonts, etc. Try as I might, I couldn't seem to find the chargen ROM listing in any of the DEC documentation archives, either.

Well, I do have a Digilent FPGA eval card and some level conversion chips laying around, so as a holiday hack project I put together a quick ROM scanner in Verilog, interfaced it to the VT52 chargen on a breadboard, and scanned out the contents. Here's a picture of the scanner in action, and the produced output:

The yellowish board on the right is the VT52 chargen. The Verilog source for the scanner, the scanned data, and some preliminary attempts to convert the data to a few modern font formats are available on my github over at https://github.com/fritzm/vt52. I need to learn some more about font formats to make some better font files; if I do I will update that repo. Any help from fontophiles gladly accepted!