NP-41 Emulator (may be)

[Chris Chung]

(04-02-2016 02:53 PM)Sylvain Cote Wrote:  First impressions ...
- I have spent about an 1 hour with the unit at this time
- I see that you have implemented a 41CV emulator.
- Very responsive keyboard, like the NP-25C v2 that I have
- The key labels placement on the PCB take some time to get used to, but after 15 minutes of usage I was fully running.
- Like the NP-25C, ENTER should be activated on both keys
- There is a bug on the power saving because a new battery is depleted within 12 hours (I am at my second new battery that I now remove when I am not testing)
- Is there a way to change the display from 4 stack display to a single line display like the real 41 ?
- When I insert the battery I am going into a some sort of test mode, could you give me more information as to how it work.
- I have not yet tested the launchpad
- Better indication as to how to insert the launchpad connector to the PCB is needed for the less technical people
- The 3D printed case is way too fragile around the launchpad connector and is breaking the case (I have removed the airline plastic bridge)

Thanks for your quick review.

- Yes it's the CV ROM, but I don't know what is missing in my implementation.
- Next PCB will have the top 4 keys in normal position as we will move battery underside.
- I noted the "Enter" key issue. Should work on both.
- Have not noticed the sleep mode failure, will check on it.
- Single line display / stack display, setup options.

When you insert new battery, you will be at the setup screen. The following keys is used
. '7' turn on beep test.
. '4' turn off beep test.
. '-' and '+', toggle / cycle contrast level of LCD.
. 'CLX' exit setup, enter calculator emulation, may need to press twice.
. other keys will show key-code, also shows battery voltage on screen. (/EDIT)

When you are in calculator mode, and pressed 'ON' to turn unit off / timeout off.
. When you turn 'ON' again w/ the following keys (press together like NP25)
. 'LN' + 'ON', s/w reset, brings you to the setup screen like when you put new battery.
. 'TAN' + 'ON', turn on backlight for LCD, only on battery > 2.8V.
. 'SST' + 'ON', toggle "single line display" / "stack display".
. 'CLX' + 'ON', like HP-41, master clear, "MEMORY LOST".
* these 4 keys are the top right side keys. (/EDIT)

It will take me a least a few days to test a new firmware, as my own unit is showing problems. I was trying to add serial flash rom to it and messed up w/ my unit. There may be some hardware design flaws w/ the internal SPI design. For Sylvain's unit, I had pre-soldered a 1M byte SPI flash but we may not be able to use it because of this fault.

Sylvain's unit already has serial bootloader and ROM upload functions. I will write another reply for instructions.