NP-25

[Chris Chung]

(10-02-2015 07:58 PM)sjthomas Wrote:  Hi Jim. No rush on the other unit.

I've already edited the startup/greeting message with no problem. However, wanting to change the message, I'd like to include the apostrophe character, and it doesn't seem to be assigned to any of the number keys. So I was thinking that if I could return it to its initial state, I'd have all those apostrophes and could just overwrite some of them with other characters.

Or, approaching it from perhaps a more direct angle, is it possible to put the apostrophe character into a message?

Unfortunately, no. The font is limited to basic alphabets. Just have not thought too much into the message thing when it was created. The only way is to modify the program and flash the firmware again. The initial state message is a void pointer w/ 0xff which just happens points to part of the flash that has segment F turn-on I believe.

[sjthomas]

(10-03-2015 09:29 PM)Chris Chung Wrote:  

(10-02-2015 07:58 PM)sjthomas Wrote:  Or, approaching it from perhaps a more direct angle, is it possible to put the apostrophe character into a message?

Unfortunately, no. The font is limited to basic alphabets. Just have not thought too much into the message thing when it was created. The only way is to modify the program and flash the firmware again. The initial state message is a void pointer w/ 0xff which just happens points to part of the flash that has segment F turn-on I believe.

Thanks for the confirmation, Chris. That is what I had come to think was the case. Great work though!!

[TomC]

Chris:

Thank you very much for your efforts, especially placing the schematic in the source code. Would you Pls detail the power distribution and switching?

Thanks,
TomC

(10-03-2015 09:29 PM)Chris Chung Wrote:  

(10-02-2015 07:58 PM)sjthomas Wrote:  Hi Jim. No rush on the other unit.

I've already edited the startup/greeting message with no problem. However, wanting to change the message, I'd like to include the apostrophe character, and it doesn't seem to be assigned to any of the number keys. So I was thinking that if I could return it to its initial state, I'd have all those apostrophes and could just overwrite some of them with other characters.

Or, approaching it from perhaps a more direct angle, is it possible to put the apostrophe character into a message?

Unfortunately, no. The font is limited to basic alphabets. Just have not thought too much into the message thing when it was created. The only way is to modify the program and flash the firmware again. The initial state message is a void pointer w/ 0xff which just happens points to part of the flash that has segment F turn-on I believe.

[Chris Chung]

(10-07-2015 02:48 PM)TomC Wrote:  Chris:

Thank you very much for your efforts, especially placing the schematic in the source code. Would you Pls detail the power distribution and switching?

Thanks,
TomC

TomC, I am not sure I understand what you mean. Do you mean the multiplexing logic? There is no much to describe regarding the power distribution as it's direct from a CR2032 button cell with a 0.1uF bypass cap.

If you can thinking of improving the firmware, let me know what is your goal and I can provide information. Bear in mind though that there are little to none flash space left.

[TomC]

Hi Chris

Sorry for my lack of clarity. Basically, is the power switch in series with the positive terminal of the battery?

[Chris Chung]

(10-08-2015 07:01 PM)TomC Wrote:  Hi Chris

Sorry for my lack of clarity. Basically, is the power switch in series with the positive terminal of the battery?

Yes, it is just a slide switch in series.

[Leviset]

I know this post is some 3 years old but I’ve only just got my NP25 calculator.
I was wondering if there is any user documentation i.e. a manual and did anyone ever get round to building a suitable case that can be bought or 3D printed please?
Dennis

[rprosperi]

(12-27-2018 11:58 PM)Leviset Wrote:  I know this post is some 3 years old but I’ve only just got my NP25 calculator.
I was wondering if there is any user documentation i.e. a manual and did anyone ever get round to building a suitable case that can be bought or 3D printed please?
Dennis

Here's a thread about a real nice 3D case Craig Bladow sells (sold?), which you can assemble around your NP25.

http://www.hpmuseum.org/forum/thread-217...#pid103503

[Craig Bladow]

If anyone in interested in an NP-25 case, send a PM with your email address and I'll reply directly with details. Thanks for the kind words, Bob.

   

(NP-25 Not Included!)