[4x5-Guy]

There was a completed cabinet devoted to outputs for the field engineer. All the register were displayed, as well as buttons to set them. At least on later systems, they were in a big square, and someone patched the OS to display the Burroughs, big B, logo during the systems idle time.

[awful]

I recall; miniature incandescent bulbs embedded into push switches that could display/set registers, it was very important to test the bulbs before trusting them (a long press) else a burned out bulb may catch you off guard. Right next to the core memory cabinet, someone accurately patched it to show huge "$" during idle time!!

[rbanffy]

The lamp test was the only button I was allowed to press on my company’s 4341.