HP 39gs and SD card

[rcpdvc]

(01-05-2018 02:52 PM)Claudio L. Wrote:  newRPL does honor the write protection switch.

Yes, it's my mistake. It was floating #WP input. I placed R67 and it is clear now. But was that behavior of newrpl the same all the time? It seems to me that somewhere you mentioned about ignoring WP, may be I'm wrong. I've checked the oldest firmware I used (v0.8 build 862) and found that it scans WP switch too.

(01-05-2018 03:42 PM)matthiaspaul Wrote:  Obviously, he just found that the #WP line does not need to be weakly pulled down to GND. However, I would advise against not populating R67, in particular if the signal would go straight to the controller. (He does not state so, but readers could get the impression that, if it seems to work without R67, the resistor might not be needed at all.)
Charge may build up depending on various conditions and open inputs do not necessarily hold "low" all the time. Also, if the voltage level happens to float in the middle region between VCC and GND, this may increase the CMOS controller's power consumption considerably (even if the calculator is switched "off").

My #WP line wasn't connected neither to R67 nor to switch (socket to footprint mismatching) at all. Floating input. Obviously I have measured #WP line voltage, have got 0V and decided that newrpl ignores WP switch because it writes with #WP=0 (WE=0) and there is nothing more to do here. It's clear now #WP line was in high state and I just pulled it down with my meter.
I'll edit my first post. Sorry for misleading. Thanks for help.