Data Logging Like It’s 1982

If you want to log voltages or resistance these days, no problem. You can buy a multimeter with Bluetooth for a hundred bucks, and if you’re really fancy you can spring for the Fluke with a graphical display that will log values automatically. Things weren’t always this cheap and easy, but there was always a way to do it.

Back in the 80s, HP had GPIB, or HP-IB, or IEEE-488 connectors on the back of their benchtop equipment. This was an 8-bit interface not unlike a parallel port that allowed for remote control of test equipment. In a great demonstration of what this was actually like, [AkBKukU] posted a video of connecting an old benchtop multimeter to a vintage computer over GPIB.

The computer used for this feat of retrotechtacularness is an HP Series 80, a footnote in the history of desktop computers, but it does have a custom CPU and BASIC in ROM. As you would expect from vintage HP gear, there are a few slots on the back of the computer for connecting interface boxes, including a modem, a speech synthesizer, and of course, an HP-IB interface that can speak IEEE-488.

With the multimeter connected to the computer over the daisy-chainable parallel interface, it was a simple matter of writing a little bit of BASIC to read a potentiometer and a thermistor. With a little bit more code, this computer can even produce a graph of the resistance over time. This is data logging like it’s 1982, and it’s a fantastic example of exactly how far we’ve come.

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Imaging And Emulating An HP-IB Disk Drive

If you look on the back of old, old test equipment, you’ll find a weird-looking connector that’s either labeled IEEE-488, GPIB, or HP-IB. It’s a very old interface designed by HP for their test equipment, and it was licensed to other manufacturers for everything from power supplies to logic analyzers. Hewlett-Packard also made computers and workstations once upon a time, and it’s no surprise this interface also made it into¬†these boxes. They even had external hard drives that operated over the HP-IB interface.

[Chris] has a few of these old computers, and wanted to see if he could emulate one of these HP-IB hard drives. There is a project to emulate these hard drives, but the electrical connection is a bit tricky; you need an IEEE-488 card, and those really aren’t made anymore.

Nevertheless, [Chris] found an old ISA IEEE-488 last year, and installed it in the PC system he’s using for all his retro explorations. After getting the card and cable to fit in the case of his PC, [Chris] connected a real HP-IB disk to his modern computer running HPDrive, made an image, and connected an old HP 150 computer. The image was read by the HP 150, and [Chris] had a vintage computer running off an emulated drive.