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HP-71B Startup Time - ROM Differences
09-08-2014, 11:57 PM
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HP-71B Startup Time - ROM Differences
I recently acquired an HP-71B with ROM version 2CDCC (at last!) and have noticed a significant difference in startup time (from press of [ON] to blinking cursor). ROM 1BBBB machines all seem to start in about 1 second, however the 2CDCC machine can take 10 seconds or more to come on, and I'm wondering if this is typical for this later ROM.

The machine passes diags and is in every way I've tried stable, functional and consistent with other machines. The s/n indicates very late 1989 production (2951A00046) and has HP-IL 1B installed.

I've verified the config is correct (OFF IO when loop is not connected, and all devices in the loop are on and loop is processing messages when connected), and all ports are readable. Also the machine performs at normal speed for programs, loop operations, etc.

Lastly, for a while right after I power down the 71 (by pressing Shift-[ON] or typing BYE or OFF) if I then power-on, it comes on in 1-2 seconds, but after a longer while, maybe a couple hours or overnight, the long startup delay occurs again.

Is this typical for a 2CDCC 71B? If not, can anyone suggest other tests or things to try?

--Bob Prosperi
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HP-71B Startup Time - ROM Differences - rprosperi - 09-08-2014 11:57 PM



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