
The 490IP1 is called an intelligent LED display because the package contains a decade counter and driver circuitry for the integrated seven-segment LED digit, complete with a carry signal that meant multiple displays could be chained together. It is notable not just due to its size, but because the glass cover makes it easy to see the die inside, as well as the wire-bonded pads.
It’s always fascinating to see glimpses of the development path that display technologies took. It’s easy to take a lot of it for granted today, but back before technology was where it is now, all sorts of things were tried. Examples we’ve seen in the past include the fantastic (and enormous) Eidophor projector which worked by drawing images onto a rotating disk of oil with an electron gun. On the smaller end of things, the Sphericular display used optics and image masks to wring a compact 0-9 numerical display out of only a few lamps at the back of a box.







So, how does it actually test? Synthesized inside the FPGA is everything the CPU needs from the motherboard to make it tick, including ROM, RAM, bus controllers, clock generation and interrupt handling. Many testing frequencies are supported (which is helpful for spotting fakes), and if connected to a computer via USB, the UCA can check power consumption, and even benchmark the chip. We can’t begin to detail the amount of thought that’s gone into the design here, from auto-detecting data bus width to the sheer amount of models supported, but you can read more technical details 
