NP-41 Emulator (may be)

[Chris Chung]

mwthomasjr, Massimo Gnerucci, Guenter Schink, Den Belillo, Didier Lacieze, Sylvain Cote, Mark Hardman, rprosperi, Raffzahn, Egan Ford

payment received for the above, will try and ship out 4 units later today.

(12-05-2017 01:57 PM)rprosperi Wrote:  Looking forward to checking it out, thanks Chris.

Is there any means to get a program in or out, other than keying?

You will need to get a usb-serial cable, 4 female-female jumper wires, and a 4 pin 0.1" pin header. And you need a terminal program that can do binary transfer. I use RealTerm under windows successfully, also tried TeraTerm recently, also works greate.

I had added a photo showing the hookup and the usb-serial device.

The following is the instructions included in your box. Please see the "serial menu" section.

Code:

    Chris Chung 2016-2017
    based on work from Eric Smith

    Operation:

    upon new battery, displays shows "NP41__=????" where ???? is the battery volatage
        pressing any key will show the internal key code, this is meant to check the soldering
        pressing "ON" then "<-" will start calculator and resets calculator memory
        pressing "ON" then "ON" will start calculator w/o resets calculator memory
            * if you lost the last value display pressing "ALPHA" a few times will force it out
        calculator will auto-shutoff in about 2 minutes of inactivity

    upon wake up from sleep, via the "ON" key, special function when press-n-hold another key
        hold "<- " while pressing "ON" key resets calculator memory
        hold "SST" while pressing "ON" key reboot calculator
            before showing "NP41  =????", display will show "V??? 201?-??" firmware version and release date briefly
            press and hold "USER" key at this point will allow calculator to enter bootloader mode
            this allows you to flash new firmware via attaching a usb-serial dongle
        hold "TAN" while pressing "ON" key clears ROM images
            this clears all four ROM slots, sometimes needed when calculator locks-up due to ROMs

    bootloader only, when main program corrupted / bricked
        remove battery, connects usb-serial dongle, then insert battery while holding "USER" key
        there will be no display shown, start Realterm on PC
        under Realterm, press "Enter" once, you should see a '?' prompt
        to flash calculator program binary, press "@" key, pressing any other key will not work
        terminal will show a '>', meaning it's ready to accept file
        select the 'Send' tab from Realterm, select bin file (i.e. NP41.bin) and send
        NP41 display will show the keytest screen when bin file flash is successful
        there will be no indication from the terminal when finish

    serial menu
        attach usb-serial dongle to calculator and PC
        enter test mode either by initial power up or via "SST" + "ON" key combination
        starts Realterm and press 'Enter' twice, the following menu will be displayed

                                         NP41 Monitor V001 2017-03
                                         (A,B,C,D) clear rom at page 1,2,3,4
                                         (1,2,3,4)  load rom at page 1,2,3,4
                                         (X) reboot
                                         (F) load focal 46 .END.

        pressing appropriate keys for corresponding action.
        for loading roms, select Realterm 'send' tab, then select and send desire rom files
        (F) to local focal program is experimental, i.e. I have not finished it

I might do a video instruction later on to show how it's done. I only tried a couple of ROMs though, Math-1C.bin and PHYSICS.bin. Focal program is non-functional.

/EDIT serial cable required, added 4 pin 0.1" pin header