Using a x-y joystick module like a dpad?

[markadr]

I am migrating some home-grown micropython code that is mostly covered by PinscapePico for a home-built mini-pinball setup (based on Batocera/Virtual pinball). It has gone well for the most part, enjoying just doing configuration rather than doing some code changes for new features (I hadn't gotten around to adding short/long press yet).

One thing I did have was some code to take the analog input from a x-y joystick module and make it look like keyboard cursor keys which works well in Batocera. In PinscapePico I have made this sort of work by using the adc option to emulate an xInput joystick but this does not work as well compared to sending simple cursor keys.

I was tight for space and am using a module like:

Thoughts?

[mjrgh]

It sounds like what you need is an ADC source for buttons, along the lines of the nudge source. Something like:

buttons: [
   { source: { type: "adc", adc: "pico_adc[0]", threshold: 49152, direction: "above" }, action: { type: "key", key: "right" },
   { source: { type: "adc", adc: "pico_adc[0]", threshold: 16384, direction: "below" }, action: { type: "key", key: "left" },
   { source: { type: "adc", adc: "pico_adc[1]", threshold: 49152, direction: "above" }, action: { type: "key", key: "up" },
   { source: { type: "adc", adc: "pico_adc[1]", threshold: 16384, direction: "below" }, action: { type: "key", key: "down" },
}

I think it would be straightforward to implement, since it's so similar to how the nudge source works, just using a different source of analog input.

(Just to clarify, this would be a new feature - it's not something that exists today.)

[markadr]

Interesting, yes that looks like it would fit the requirement nicely. I am not a C++ guy but would be happy to take a look with some pointers as to where to start.

[mjrgh]

If you want to take a stab at it, a good starting point should be class Button::NudgeDeviceSource (defined firmware/buttons.h and .cpp). The ADC source should work roughly the same way. The analog data would come from a class ADC object, which you'd find by via adcManager.Enumerate() (you'd enumerate the available devices and match them against the name specified in the config).

[markadr]

Thanks for the pointers. I have made a start, will see how far I get over the weekend.

[markadr]

Progress, I have something that works locally after a bit of messing about. I couldn't get the GUI to rebuild due to some issue with the NuGet packages missing but fortunately the current one still allows for unknown config to be applied so I could test out my changes. In the Button tab view I can see the cursor keys being activated, they just come up as Unkown source.

The work-in-progress commit is markadr@95680bc

Still to be worked on is an updated reference section for this new source and teaching the GUI about the new syntax, need to get the GUI to build to test this. Feedback welcomed....

A snip of the config, I set the button of the joystick to be a classic GPIO and then added my new adc based source for the rest:

buttons: [
       {
           source: { type: "gpio", gp: 15, active: "high"},
           action: { type: "key", key: "esc" },
        },
        {
            source: { type: "adc", adc: "pico_adc[1]", threshold: 3000, above: true },
            action: { type: "key", key: "up"}
        },
        {
            source: { type: "adc", adc: "pico_adc[1]", threshold: 2000, above: false },
            action: { type: "key", key: "down"}
        },
        {
            source: { type: "adc", adc: "pico_adc[0]", threshold: 2000, above: false },
            action: { type: "key", key: "left"}
        },
        {
            source: { type: "adc", adc: "pico_adc[0]", threshold: 3000, above: true },
            action: { type: "key", key: "right"}
        }
    ],

With some debug enabled

0000/01/01 00:00:00 Config:  Config file loaded OK; parsed JSON memory usage: 6,024 bytes
0000/01/01 00:00:00 Config:  Pico ADC configured; 2 channels, GPIOs 26,27,
0000/01/01 00:00:00 Info:    Pico ADC configured; clock div 95.00, DMA channels 0,1, round-robin mask 0x03
0000/01/01 00:00:00 Config:  USB CDC console enabled, output buffer size 8192, history size 256
0000/01/01 00:00:00 Config:  Button 0: Pushbutton created, action Key(0x29), source GP15, shift(mask 00, bits 00)
0000/01/01 00:00:00 Debug:   ADCSource: added key pico_adc for Pico on-board ADC
0000/01/01 00:00:00 Debug:   ADCSource: added subkey pico_adc[0] for Pico on-board ADC
0000/01/01 00:00:00 Debug:   ADCSource: added subkey pico_adc[1] for Pico on-board ADC
0000/01/01 00:00:00 Debug:   ADCSource: ADC "pico_adc[1]" selected
0000/01/01 00:00:00 Config:  ADCSource: Pico on-board ADC, 1 above, 3000
0000/01/01 00:00:00 Debug:   ADCSource: fullName ADCSource(Pico on-board ADC 1 above 3000), ADC min (0), max (4095)
0000/01/01 00:00:00 Config:  Button 1: Pushbutton created, action Key(0x52), source ADCSource(Pico on-board ADC 1 above 3000), shift(mask 00, bits 00)
0000/01/01 00:00:00 Debug:   ADCSource: added key pico_adc for Pico on-board ADC
0000/01/01 00:00:00 Debug:   ADCSource: added subkey pico_adc[0] for Pico on-board ADC
0000/01/01 00:00:00 Debug:   ADCSource: added subkey pico_adc[1] for Pico on-board ADC
0000/01/01 00:00:00 Debug:   ADCSource: ADC "pico_adc[1]" selected
0000/01/01 00:00:00 Config:  ADCSource: Pico on-board ADC, 1 below, 2000
0000/01/01 00:00:00 Debug:   ADCSource: fullName ADCSource(Pico on-board ADC 1 below 2000), ADC min (0), max (4095)
0000/01/01 00:00:00 Config:  Button 2: Pushbutton created, action Key(0x51), source ADCSource(Pico on-board ADC 1 below 2000), shift(mask 00, bits 00)
0000/01/01 00:00:00 Debug:   ADCSource: added key pico_adc for Pico on-board ADC
0000/01/01 00:00:00 Debug:   ADCSource: added subkey pico_adc[0] for Pico on-board ADC
0000/01/01 00:00:00 Debug:   ADCSource: added subkey pico_adc[1] for Pico on-board ADC
0000/01/01 00:00:00 Debug:   ADCSource: ADC "pico_adc[0]" selected
0000/01/01 00:00:00 Config:  ADCSource: Pico on-board ADC, 0 below, 2000
0000/01/01 00:00:00 Debug:   ADCSource: fullName ADCSource(Pico on-board ADC 0 below 2000), ADC min (0), max (4095)
0000/01/01 00:00:00 Config:  Button 3: Pushbutton created, action Key(0x50), source ADCSource(Pico on-board ADC 0 below 2000), shift(mask 00, bits 00)
0000/01/01 00:00:00 Debug:   ADCSource: added key pico_adc for Pico on-board ADC
0000/01/01 00:00:00 Debug:   ADCSource: added subkey pico_adc[0] for Pico on-board ADC
0000/01/01 00:00:00 Debug:   ADCSource: added subkey pico_adc[1] for Pico on-board ADC
0000/01/01 00:00:00 Debug:   ADCSource: ADC "pico_adc[0]" selected
0000/01/01 00:00:00 Config:  ADCSource: Pico on-board ADC, 0 above, 3000
0000/01/01 00:00:00 Debug:   ADCSource: fullName ADCSource(Pico on-board ADC 0 above 3000), ADC min (0), max (4095)
0000/01/01 00:00:00 Config:  Button 4: Pushbutton created, action Key(0x4F), source ADCSource(Pico on-board ADC 0 above 3000), shift(mask 00, bits 00)
0000/01/01 00:00:00 Info:    Kb LED 00
2025/07/27 08:05:37 Debug:   File "config.json" opened for read, 36414 us

[markadr]

Worked out how to rebuild the UI so I updated the reference docs and checked that also worked when saving the updated config. Latest bits are in my branch - https://github.com/markadr/PinscapePico/tree/button-source-adc

[markadr]

@mjrgh any obections if I was to turn this into a pull request?

[mjrgh]

Definitely no objection! This would be a useful feature to add the base code.

[markadr]

Now avaliable as part of https://github.com/mjrgh/PinscapePico/releases/tag/v0.1.18