On Thu, Aug 13, 2020 at 1:19 PM Henry Bent wrote: so this damn teeny tiny display would cycle through a sequence of codes >> that told you what the machine was doing; it came with a book that told you >> what each code meant. Something like "387" meant mounting /usr. Ugh; I just >> found a page on ibm.com describing these "IPL codes." >> > IPL = Initial Program Load = boot(strap), by the way. It also has the connotations of "toggle in". Seated one day at the keyboard I was weary and ill at ease, And my fingers rattled noisily Over the clicking keys I know not what I was coding Nor what I had IPLed in But I struck one chord of logic Like the sound of a great IF-THEN. --Guy Steele (I think) But this reminded me: Does anyone remember a system of any sort where there were *two* corresponding sets of alphanumeric error codes, one short and meaningless like F32 and the other somewhat meaningful like POWER_LOW? I made up this example, but I have a feeling I saw or read about such a system. I can't pin it down with Dr. Google. I already know about plenty of systems that have *numbers* and alphabetics, like , or just alphabetics and a (localizable) text explanation, like VMS, or just a number and a text explanation, like the BIOS errors. Such number-only error systems are still very common in things like "smart" washing machines, where the cost and unreliability of a non-tiny screen simply isn't acceptable. John Cowan http://vrici.lojban.org/~cowan cowan@ccil.org Wer es in kleinen Dingen mit der Wahrheit nicht ernst nimmt, dem kann man auch in grossen Dingen nicht vertrauen. --Albert Einstein on honesty