Stop/continue While loop block

[Larz60+]

Documents for MCP2221A:

• Datasheet:
  • Data sheet MCP2221A: https://ww1.microchip.com/downloads/en/D...05565C.pdf
    
• Firmware:
  • MCP2221 I2C/SMBus Terminal (v2.0.1): https://ww1.microchip.com/downloads/en/D...rminal.zip
    
  • MCP2221 Utility (v1.0.2): https://ww1.microchip.com/downloads/en/D...tility.zip
    
  • MCP2221 DLL (v2.1.1): https://ww1.microchip.com/downloads/en/D...21_DLL.zip
    
  • MCP2221 DLL (v2.2.1): https://ww1.microchip.com/downloads/en/D...2.2.1).zip
    
  • MCP2221 Command Line Interface (v1.0.2): https://ww1.microchip.com/downloads/en/D...221CLI.zip
    
  • MCP2221 Java Native Interface (v1.0): https://ww1.microchip.com/downloads/en/D...erface.zip
    
  • MCP2200/MCP2221 Windows Driver & Installer: https://ww1.microchip.com/downloads/en/D...-10-09.zip
    
  • MCP2221 DLL: https://ww1.microchip.com/downloads/en/D..._06_17.zip
    
  • MCP2200/MCP2221 Linux Driver Information: https://ww1.microchip.com/downloads/en/DeviceDoc/
  • MCP2200_MCP2221_CDC_Linux_Readme.txt
    
  • MCP2221 Linux Kernel I2C Bus Driver: https://ww1.microchip.com/downloads/en/D...0_1.tar.gz
    
  • MCP2221 Terminal Android App (v2.0): https://ww1.microchip.com/downloads/en/D...(v2.0).zip
    

The writeup on the Neotrellis board here: https://learn.adafruit.com/adafruit-neotrellis?view=all
states: These 4x4 button pad boards are fully tile-able and communicate over I2C. With 5 address pins, you've got the ability to connect up to 32 together in any arrangement you like. With our trusty seesaw I2C-to-anything chip, you don't even need to manage the NeoPixel driving. That's right! Both the button management and LED driving is completely handled for you all over plain I2C. With both Arduino/C++ and CircuitPython/Python library support, you can use these pads with any and all microcontroller or computer boards.

Documents for ATSAMD09D14A-MU:

• Data Sheets:
  • SAM D09 Datasheet Summary: https://ww1.microchip.com/downloads/en/D...ummary.pdf
    
  • SAM D09 Datasheet: https://ww1.microchip.com/downloads/en/D...asheet.pdf
    
• Supporting Collateral:
  • MPLAB Harmony v3 Synchronous Drivers and Their Usage in FreeRTOS-Based Applications: https://ww1.microchip.com/downloads/en/D...03290A.pdf
    
  • The Difference Between MPLAB Harmony v3 PLIBs and Drivers, and When to Use Them: https://ww1.microchip.com/downloads/en/D...03291A.pdf
    
  • Build MPLAB Harmony v3 Project with Arm GCC Toolchain in MPLAB X IDE: https://microchip-mplab-harmony.github.i...eadme.html
    
  • How to Setup MPLAB Harmony v3 Software Development Framework: https://ww1.microchip.com/downloads/en/D...03232C.pdf
    
  • How to Use the MPLAB Harmony v3 Debug System Service: https://ww1.microchip.com/downloads/en/D...03246A.pdf
    
  • EEPROM Emulation for Flash-Only Devices Tech Brief: https://ww1.microchip.com/downloads/en/D...03222A.pdf
    
  • What is Sleepwalking? How it Helps to Reduce Power Consumption: https://ww1.microchip.com/downloads/en/D...03183A.pdf
    
  • How the Event System Helps to Lower CPU Load TB: https://ww1.microchip.com/downloads/en/D...03170A.pdf
    
• Application Notes:
  • AN3346 - Introduction to MPLAB X IDE and MPLAB Harmony v3 for Atmel Studio and ASF users: http://www.microchip.com/wwwappnotes/app...=en1001251
    
  • AN2466 - Using Atmel-ICE for AVR Programming In Mass Production: http://www.microchip.com//wwwAppNotes/Ap...e=en599598
    
  • AN2468 - Production Programming of Microchip AVR and SAM Microcontrollers: http://www.microchip.com//wwwAppNotes/Ap...e=en592074
    
  • AN2584 - Integrated Power Factor Correction (PFC) and Sensorless Field Oriented Control (FOC) System for Microchip 32-bit Microcontrollers Application Note: http://www.microchip.com//wwwAppNotes/Ap...e=en601573
    
  • AN2520 - Sensorless Field Oriented Control (FOC) for a Permanent Magnet Synchronous Motor (PMSM) Using a PLL Estimator and Equation-based Flux Weakening (FW) Application Note: http://www.microchip.com/wwwAppNotes/App...e=en599773
    
  • AN2587 - EMI, EMC, EFT, and ESD Circuit Design Consideration for 32-bit Microcontrollers Application Note: http://www.microchip.com//wwwAppNotes/Ap...e=en601525
    
  • AN_42336 - AT09331: ASF USB Stack Manual: http://www.microchip.com/wwwappnotes/app...e=en591964
    
  • AN_42382 - AT04056: Getting Started with FreeRTOS on SAM Flash MCUs: http://www.microchip.com//wwwAppNotes/Ap...e=en591621
    
  • AN_42411 - AT06549: Ultra Low Power Techniques: http://www.microchip.com//wwwAppNotes/Ap...e=en591078
    
  • AN_42472 - AT11491: Peripheral Power Consumption in Standby Mode for SAM D Devices: http://www.microchip.com//wwwAppNotes/Ap...e=en590886
    
  • AN_42362 - AT06467: Getting Started with SAM D09/D10/D11: http://www.microchip.com//wwwAppNotes/Ap...e=en591637
    
  • AN_42393 - AT09381: SAM D - Debugging Watchdog Timer Reset - AT09381: SAM D - Debugging Watchdog Timer Reset: http://www.microchip.com//wwwAppNotes/Ap...e=en590880
    
• Board Design Files:
  • STK600-RC032SAM-79: https://ww1.microchip.com/downloads/en/D...SAM-79.pdf
    
  • STK600-RC032SAM-89: https://ww1.microchip.com/downloads/en/D...89_sch.pdf
    
  • STK600-RC048SAM-78: https://ww1.microchip.com/downloads/en/D...matics.pdf
    
  • STK600-RC048SAM-88: https://ww1.microchip.com/downloads/en/D...88_sch.pdf
    
  • STK600-RC064SAM-72: https://ww1.microchip.com/downloads/en/D...matics.pdf
    
  • STK600-RC064SAM-87: https://ww1.microchip.com/downloads/en/D...87_sch.pdf
    
• Code Examples:
  • Fitness Tracker Application Demo on SAM D21 Curiosity Nano Evaluation Kit and Curiosity Nano Base for Click boards using MPLAB Harmony v3: https://github.com/Microchip-MPLAB-Harmo...racker.zip
    
  • Getting Started Application Demo on SAM D21 Curiosity Nano Evaluation Kit using MPLAB Harmony v3: https://github.com/Microchip-MPLAB-Harmo...tarted.zip
    
  • Location Tagged SOS Application Demo on SAM D21 Curiosity Nano Evaluation Kit and Curiosity Nano Base for Click boards™ using MPLAB Harmony v3: https://github.com/Microchip-MPLAB-Harmo...on_sos.zip
    
• More: https://www.microchip.com/wwwproducts/en/ATSAMD09D14
  

The trusty seesaw I2C-to-anything chip can be seen here: https://learn.adafruit.com/adafruit-sees...9-breakout
it provides:

• 3 x 12-bit ADC inputs
  
• 3 x 8-bit PWM outputs
  
• 7 x GPIO with selectable pullup or pulldown
  
• 1 x NeoPixel output (up to 63 pixels)
  
• 1 x EEPROM with 64 byte of NVM memory (handy for storing small access tokens or MAC addresses)
  
• 1 x Interrupt output that can be triggered by any of the accessories
  
• 2 x I2C address selection pins
  
• 1 x Activity LED
  

Pinouts for seesaw: https://learn.adafruit.com/adafruit-sees...ut/pinouts

this should connect directly to the MCP2221A which should plug directly into USB-A port and be readable by python.
I will work out details when I have the hardware.

I wrote the code (In 'C', Not python) for the keypad on a well known commercial fish finder with a TI msp430 MCU and made it entirely interrupt driven. I still have that code if I need to fall back on it. It was written for any 4 x 4 matrix.

There should be no need for the raspberry pi.

Check out the last post on this Adafruit thread about interrupt with Python

https://forums.adafruit.com/viewtopic.php?f=50&t=173615

This doesn't worry me yet. I've done a lot of embedded hardware work, starting back in the early 1980's with the intel 8080A.
I think (won't swear to it yet) I can make it work