Vintage Terminal Converted For Galactic Use In Time For May The Fourth

“Not as clumsy or random as Windows. An elegant terminal, for a more civilized age.” [Ben Kenobi] might well have said that about the Hewlett-Packard 264x-series of serial terminals, in use starting at just about the time the original installment of the Star Wars franchise was released.  With their wide-screen CRTs and toaster-oven aesthetic, they were oddballs in the terminal market, and [CuriousMarc] has gone and made one even odder by converting an H-P 2645A to display the Aurebesh character set from the movies.

A look under the hood of this lovely bit of retrocomputing history makes one think the designers almost foresaw the need to add support for a made-up language nearly half a century later. The terminal has a backplane and bus for pluggable cards, one of which carries the ROMs that [Marc] extracted and reprogrammed with the Aurebesh characters. He had a little trouble at first, needing to bodge the chip select and forgetting that he had made other “special modifications” to the terminal. The video below shows the results, along with some fatherly mortification of his daughters and a suitable tribute to the lately late [Peter Mayhew], he who donned the Wookiee suit and made a seven-foot space Sasquatch lovable.

Need more for you “May the Fourth” fix? How about a clumsy and random blaster, a cosplay speeder bike, or a fleet of droids?

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Blast From The Past With Space Station PROM Reader

The Ursa Major Space Station SST282 is a dinosaur of a digital reverb.  Okay, so maybe 1978 isn’t ancient yet, but it is getting to the point where one has to worry about the possibility of component failure.  At least that’s what [Obsoletetechnology] thought when they created a backup of its memory contents.

As can be seen from some of Hackaday’s previous articles, a part does not have to be an older one to fail.  However, there is no such thing as being too paranoid when it comes to older parts reaching their lifetime.  Especially when there is valuable memory involved.  Each bit of PROM memory is locked by a fuse on its location grid to store permanent data.  To be able to read this and collect the respective data, a Raspberry Pi 3 PROM reader was created.

The SST282 uses 3 TTL-level 74xx series Schottky PROM memories on board that hold RAM lookup tables.  In the case that these failed, all of the subsequent information would be lost since there are no surviving memory dumps online.  Fortunately we are interested only in gathering their contents, so the PROM reader schematic is fairly rudimentary.  The chip’s address and data buses connect to a Pi’s GPIO header, and the only other thing to note is a 74LS541 TTL level shifter that converts the Pi’s 3.3V output to the PROM’s 5V TTL level.

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Weird CPU

How many instructions does [agp.cooper’s] computer have? Just one. How many strip boards does it use? Apparently, 41 five 41-track boards. While being one shy from the answer to life, it is still a lot of boards for a single instruction. The high board count is due to the use of 1970’s vintage ICs including TTL parts, 2114 RAM chips, and 74S571 PROMs.

There are several different architectures for single instruction computers and [agp’s] uses what is technically at TTA (transfer-triggered architecture). That is, the one instruction is a move and the destination or source of the move determines the operation. For example, the Wierd CPU (that’s the name of it) has a P and Q register. If you load those registers and then the ADD register will contain the sum of the two numbers.

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Dumping Old PROMs With New Hardware

[ijsf] recently came across a very old synthesizer from a defunct West German company. This was one of the first wavetable synths available, and it’s exceptionally rare. Being so rare, there isn’t much documentation on the machine. In an attempt at reverse engineering, [ijsf] decided to dump the EPROMs and take a peek at what made this synth work. There wasn’t an EPROM programmer around to dump the data, but [ijsf] did have a few ARM boards around. It turns out building a 27-series PROM dumper is pretty easy, giving [ijsf] an easy way to dig into the code on this machine.

The old EPROMs in this machine have 5v logic, so [ijsf] needed to find a board that had a ton of IOs and 5v tolerant inputs. He found the LPC2148, which has a nice USB system that can be programmed to dump the contents of a PROM over serial. Interfacing the PROM is as simple as connecting the power and ground, the address lines, data, and the signal lines. After that, it’s just a matter of stepping through every address according to the timing requirements of the PROM. All the data was dumped over a serial interface, and in just a few seconds, [ijsf] had 32768 bytes of ancient data that made this old synth tick.