Which calculators had no known bugs?

[PANAMATIK]

(11-13-2017 08:13 PM)teenix Wrote:  That is true and it isn't true. :-)

Looking at the microcode, during a running program, the HP29c doesn't test for a key press when it is executing these programmed keys...

0 - 9, CLx, EEX and CHS

Tony

Thanks Tony for this exquisite deep look inside the code.

The intention of the HP engineers now becomes clear. If you have a sequence of number entry in your program like 123.45 CHS EEX 5, R/S (manual stop) should not break the number into two parts when restarted. Great idea.

I admit that it is very unlikely to have a nonsense program, which consists only of numbers. Therefore nobody has found this endless loop in the last 40 years. I did, because I tested the correct storage of a complete 98 step program in the LP circuit flash memory, entered all 1s and accidentally started the program.

Bernhard