I've got a Perma 6048 that I've trying to put into Cal mode. It just won't!
The switch on the rear panel works OK, AFAICT when in the Cal position it connects ~WE on the DS1220 (pin 21) and ~W on the $864 SRAM (pin 27) to a 4K7 pullup to +5V and to the output of an LS00 which should be strobing the Write lines low as needed. I can't see any way in which the processor can be informed of the switch setting! In measure mode it just connects ~WE on the DS1220 to a 10k pullup to +5V. The schematic is on page 120 (Figure 11.4) of the user manual and also page 9-7 of the service manual. Clearly I'm missing something - as a friend reports that his does go into cal mode. Confused ... Thanks Dave _______________________________________________ volt-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.
