HP-71B Startup Time - ROM Differences

[rprosperi]

(09-09-2014 01:13 PM)J-F Garnier Wrote:  The DISPLAY IS :DISPLAY is the default power-up state (first insertion) of the HP-IL module. So unless an explicit DISPLAY IS * is done, the HP-71B will search for a display at every turn-on, even if the loop is open or broken, causing a delay. PRINTER IS will not cause any problem, until you do a printer operation (PRINT, PLIST, ...).

So this 71B still comes up with a 10+ second delay, even after doing DISPLAY IS *, RESET HP-IL and OFF IO. I read in the thread J-F pointed to that OFF IO resets DISPLAY IS and PRINTER IS assignments, so maybe a better sequence would be OFF IO followed by DISPLAY IS *.

Anyhow, the basic issue has been answered, it's not the ROM, so it's just this machine has some weird config inside, so I'll probably just INIT:3, wipe all RAM and build it again. But I will explore it a bit longer, just because I want to know what the cause is. Curiosity is such a bitch.

Regardless of the initial casue, a key thing I don't understand is why does the amount of time i wait after shutdown affect the next startup behavior? Do things really happen in a powered off 71 several hours after shutdown?

Thanks to all who replied; as usual, lots of useful and interesting info.