2021 - RubyKaigi - It is time to build your mruby VM on the microcontroller?

In 2020, I find a mini-arcade maker product that uses ESP8622 and MicroPython. Since I know the mruby/c can run on the ESP32 but it doesn't support running on the ESP8622. Is it possible to implement our own mruby VM and execute Ruby on any microcontroller we want to use it? This talk will show my progress to run a simple mruby script on the ESP8622 by implementing my own small mruby VM.

Transcript

1. It is time to build your mruby VM
   on the microcontroller?
   Photo by Johannes Plenio from Pexels
   

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2. THE ENGINEER
   
   
   OF CREATIVE
   ૵
   ࣌
   ݭ໵
   @elct9620
   

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5. Does build a mruby VM is hard
   Question
   

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6. Yes, but we can do it easier
   My Answer
   

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7. This is my
   fi
   rst time trying it, how can I start it?
   Question
   

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8. mruby-L1VM
   

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9. A mruby VM running on the Web only ~1000 lines
   mruby-L1VM
   

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10. Everyone can read it without spending a lot of time
    mruby-L1VM
    

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11. How does it work?
    mruby-L1VM
    

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12. Start Program End Program
    Read Byte Code Execute Exit?
    No
    Yes
    IREP OPCODE
    

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14. How to read the IREP from mrb binary?
    IREP
    

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18. example.mrb
    RITE Header
    IREP
    Debug Section
    

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19. example.mrb
    RITE Header
    IREP
    Debug Section
    34 bytes
    

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21. example.mrb
    RITE Header
    IREP
    Debug Section
    IREP Header
    

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23. IREP
    ISEQ
    Pools
    Symbols
    Sub-IREP
    OPCODE
    

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27. Sample Code
    

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28. IREP
    ISEQ
    Pools
    Symbols
    Sub-IREP
    Ex. String
    

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30. How does the "method" work in mruby?
    Call Method
    

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31. IREP
    ISEQ
    Pools
    Symbols
    Sub-IREP
    Method
    Name
    

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32. IREP
    ISEQ
    Pools
    Symbols
    Sub-IREP
    Method Body
    

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34. Pointer
    

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38. Sample Code
    

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41. Run your VM on the microcontroller
    Demo
    

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43. Prototype Code
    Series Article (Chinese)
    

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44. I am trying to build my own plant keeper IoT device
    The Next
    

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45. Thanks
    

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