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 <errno.h>, 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.