Touch points and buttons on M5Core 2" displays, Tab 5" display, and Sunton 7" display for keyboard emulation

I have targeted the following M5 Stack models with my C64/C128/Vic-20/Apple 1 emulator:

• M5Stack Fire IoT
• M5 Core2
• M5 CoreS3

(Even though I have targeted other boards, I had only implemented touch on the CoreS3)

The primary reason for targeting these boards was the common 2" 320x240 display perfect for most C64 emulation, and the availability of a wristband that works with Core2 and CoreS3 (it works with the Fire if and only if you never need to charge the battery - not aware of a universe where that works out long term).

[aside... Originally I had supported the M5 Core Basic, but without PSRAM, it was difficult to support the different computer models that currently load into that memory.  So M5 Core BASIC was dropped after its initial development.]

The Basic and Fire have three UI hardware buttons.   The Core2 has three virtual touchscreen buttons (touchscreen expands farther down from the LCD screen to allow for capacitive touch button points, and the M5 library abstracts them similar to physical buttons, so your code doesn't even have to know the difference).  The CoreS3 has no UI buttons, but I've manually implemented virtual touch screen buttons at the bottom of the screen.   From left to right the buttons are known to M5 as A, B, and C.

So button support for Basic, Fire, and Core2 was straightforward.

• press Button A: Cursor UP
• press Button B: RETURN
• press Button C: Cursor Down

With hold functionality as well.

• hold Button A: toggle computer model (C64, C128, Vic-20, Apple 1, repeats)
• hold Button B: LOAD"*",8 / RUN for Commodore, snapshot system for Apple 1
• hold Button C: STOP

Thus, one can demonstrate the emulator loading a menu of programs, scrolling though the listing, and choosing one.  And toggle between the emulators.   The Apple 1 snapshot system allows choosing a snapshot and loading or saving it.

I support other hardware targets, and I have BLE pairing functionality.  So I am thinking of expanding support of the virtual buttons, including more virtual buttons, and providing 8-position joystick inputs (and button) too.  But for now, here is the documentation for the existing buttons.

And then just like that, the CoreS3, Tab5, and Sunton 7" now have more touch points implemented for their capacitive touch screens to allow for more virtual keys.

Added Tab5 Keyboard support for my portable emulators for Commodore

 

Tab5 Keyboard is a convenience add-on

I added native keyboard support to my emulators already running on M5Stack's Tab5.

There were already 64/Vic-20/128 original keyboards, CardKB, web page adapter, Palm Portable Keyboard, and custom BLE support.  

Now there is also attached keyboard accessory support.  The Tab5 is a 5" ESP32-P4 handheld tablet with high resolution 1280x720 LCD.  The keyboard plugs into the bottom of the tablet, extending the size, and the capabilities.

The implementation scans all 70 keys for presses and translates to a list of C128 key scan codes into ASCII comma separated and newline terminated form, which the emulators already know how to translate into Commodore model specific keyboard scan codes.  As these are pressed scan codes, the press is persisted in the emulated system until the physical key is released.  These are symbolic mappings, not positional mappings because that is my preference.  Want different?  This is open source!

All visibly labeled keys are supported mostly as is.  Keys not Commodore specific are mapped to a Commodore PETSCII character already mapped to the proper ASCII character for the minimal environment (left arrow, underscore, caret, curly braces, pipe, backslash, backquote, tilde).  In addition, shift [Aa] supports letters, and numbers and punctuation to do the normal shifted characters.  Both [sym] and shift [Aa] do the symbols.   Additional keys worthy of documentation are:

• _=             RIGHT SHIFT
• tab            COMMODORE C=
• sym tab        TAB
• esc            STOP
• shift esc      LOAD RUN
• sym esc        ESC
• ctrl sym del   STOP RESTORE
• shift del      INSERT
• \              £
• sym shift \    SHIFT £
• shift -        LEFT ARROW
• sym shift -    SHIFT -
• shift +        =
• sym shift +    SHIFT =
• sym shift *    SHIFT *
• sym up         HOME
• sym shift up   CLEAR
• sym 1          F1
• ...
• sym 8          F8

As a reminder the emulators included are:

• Commodore 64
• Commodore 128
• Commodore Vic-20
• Environment similar to an Apple 1 (minimalistic 6502/6850/ROM/RAM plus terminal)

Links:

https://github.com/davervw/c-simple-emu6502-cbm/tree/unified-pio