WP34s flash technical erase procedure

[MarkHaysHarris777]

Never mind. :-} I finally understand whats happening. I have one of my calculators in that frustrating mode (following one erase cycle) where the machine appears dead. I have confirmed that the erase cycle, power-on, reset works; but no flash, yet, because MySamba can't negotiate with the stupid Prolific chip-set in my Dynex USB-Serial converter. Its a great null modem to me headless workstations, just can't use it to flash. rats. I'm still waiting on my FTDI converter to come by the mails. I get the infamous 'unable to connect' message; so I reset and unplugged everything.

I noticed something Jebem noted some days back, that even though the 'erased' machine appears dead its possible to check the voltage drop on the reset pin after a power-on. Even though the machine appears dead the voltage on J33 (reset) comes up to just less than Vcc (and stays there) until 'reset' is pressed; the voltage on pin J33 then drops to zero until the next power-on.

An inverter will power the unit, but I not think the forward + current has enough guts for the flash operation/ scrubbing that idea. I'll either go with a temp three volt power pack, or just wait until the LM117 gets here.

Lator gators... I'll be updating my PhotoJournal page later this morning when I get my pics processed.