Tablet terminals show legacy hardware never vanishes

Terminals launched legacy systems into orbit. Before there were PC alternatives, legacy systems used code built for custom terminals. VT 520, HP 2392: Legacy applications targeted such vendor-customized hardware.

The rise of the emulator began early. It’s also launched itself into the iOS world during the past seven years. One vendor sells a product that emulates a vast range of legacy terminals. In 2013 TTerm Pro entered the market as a solution for fully mobile legacy terminal use.

Finding such a terminal in the wild is rare today. The software that needs it, though, may still be on the job. Development started in 2013 for TTerm Pro. The iOS app from TTWin, all of $19.95, is getting maintenance and bug updates once more. ALT key issues for several European-language software keyboards, including DEC VTs, now run correctly.

In this year’s version 1.5.0, Bluetooth scanners no longer inject CR characters midway through barcode scanning. The fact that Bluetooth has anything to do with legacy hardware such as terminals is worth a closer look.

It’s mind-boggling to consider that an HP 2392, launched in 1984, is emulated 36 years later. That text-only terminal, if you can find one, cost $1,295 when it was new. The 12 inches of CRT screen produced characters on a 7×12 dot matrix. HP included a tilt and swivel base for each terminal.

It was a different world in 1984. “The most common cause of failure,” says the HP Computer Museum collector notes, “is a bad power supply. The first step in refurbishing these terminals is to remove the top case and remove the power supply PCB. (Printed Circuit Board) This PCB contains some metalized paper capacitors that are prone to failure and smoking with age. These capacitors are easily replaced.”

That replacement is true if you’ve got a source for paper capacitors. PCs gave the world more emulation options, eventually getting terminals portable via laptops. Today there’s a resource for legacy hardware in many forms. Stromasys sells Charon to use Intel servers for emulating VAX and PA-RISC hardware. And TTerm uses a $1,250 iPad Pro, about 13 inches in size, to carry terminal access anywhere we find a cell signal.

Hardware never dies when good emulation engineering keeps it alive. Download the TTerm Pro app and marvel at the time machine bounty. In 1984, that $1250 delivered 7×12 matrix characters. Nothing else on that 12 inches, not like the iPad Pro of today. One important reason to preserve legacy terminals: Companies continue to use the software that relies on them.

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