HP-71B Chirp (solved)

[Sylvain Cote]

(09-17-2019 06:15 PM)J-F Garnier Wrote:  According to your observations, the chirp happens each time the HP71 exits sleep state: key pressed, blinking cursor (software blinking), one-minute periodic battery-checking (when idle and no blinking cursor), end of DELAY.
It can be due to either software (bad configuration) or hardware (weak shortcut between a bus line and the speaker line, bad cpu i/o).

I thought as much.

(09-17-2019 06:15 PM)J-F Garnier Wrote:  Can you check:
- check if any LEX file present, if yes remove them.
- remove any external modules (RAM, ROM, HPIL), does it change anything?
- check MEM and that the 4 internal 4k ports are not FREEd, if not CLAIM that ports. Any effect?
- Basic reset (INIT 1). Any effect?
- master software reset (INIT 3). Any effect?

I did several INIT 1 and INIT 3, I also did a INIT 2 to check ROMs just in case but to no avail.

(09-17-2019 06:15 PM)J-F Garnier Wrote:  - last resort, hardware reset: remove the batteries - at least one - and discharge the internal power supply. Remember to shortcut the supply lines not at the battery terminals but in the card reader slot, see here.

I also did several battery removal and shortcut supply lines ... at the battery terminal ... ... damn, I got burned again, completely forgot to do it at the card reader slot ... I will do it tonight.

Merci Jean-François. (and Robert)

Sylvain