[Docs] Add AVR and ARM examples to GPIO Commands (#6942)

* [Docs] Add AVR and ARM examples to GPIO Commands

Add examples for reference for people not as well versed in microcontroller coding, such as myself.

* Apply suggestions from code review

Co-Authored-By: fauxpark <fauxpark@gmail.com>
Co-Authored-By: noroadsleft <18669334+noroadsleft@users.noreply.github.com>

diff --git a/docs/internals_gpio_control.md b/docs/internals_gpio_control.md
index 51a549f..8b83513 100644 (file)
--- a/docs/internals_gpio_control.md
+++ b/docs/internals_gpio_control.md
@@ -6,18 +6,17 @@ QMK has a GPIO control abstraction layer which is microcontroller agnostic. This
 
 The following functions can provide basic control of GPIOs and are found in `quantum/quantum.h`.
 
-|Function              |Description                                                       |
-|----------------------|------------------------------------------------------------------|
-|`setPinInput(pin)`    |Set pin as input with high impedance (High-Z)                     |
-|`setPinInputHigh(pin)`|Set pin as input with build in pull-up                            |
-|`setPinInputLow(pin)` |Set pin as input with build in pull-down (Supported only on STM32)|
-|`setPinOutput(pin)`   |Set pin as output                                                 |
-|`writePinHigh(pin)`   |Set pin level as high, assuming it is an output                   |
-|`writePinLow(pin)`    |Set pin level as low, assuming it is an output                    |
-|`writePin(pin, level)`|Set pin level, assuming it is an output                           |
-|`readPin(pin)`        |Returns the level of the pin                                      |
+|Function              |Description                                                       | Old AVR Examples                               | Old ChibiOS/ARM Examples                        |
+|----------------------|------------------------------------------------------------------|------------------------------------------------|-------------------------------------------------|
+|`setPinInput(pin)`    |Set pin as input with high impedance (High-Z)                     | `DDRB &= ~(1<<2)`                              | `palSetLineMode(pin, PAL_MODE_INPUT)`           |
+|`setPinInputHigh(pin)`|Set pin as input with builtin pull-up resistor                    | `DDRB &= ~(1<<2); PORTB \|= (1<<2)`             | `palSetLineMode(pin, PAL_MODE_INPUT_PULLUP)`    |
+|`setPinInputLow(pin)` |Set pin as input with builtin pull-down resistor                  | N/A (Not supported on AVR)                     | `palSetLineMode(pin, PAL_MODE_INPUT_PULLDOWN)`  |
+|`setPinOutput(pin)`   |Set pin as output                                                 | `DDRB \|= (1<<2)`                               | `palSetLineMode(pin, PAL_MODE_OUTPUT_PUSHPULL)` |
+|`writePinHigh(pin)`   |Set pin level as high, assuming it is an output                   | `PORTB \|= (1<<2)`                              | `palSetLine(pin)`                               |
+|`writePinLow(pin)`    |Set pin level as low, assuming it is an output                    | `PORTB &= ~(1<<2)`                             | `palClearLine(pin)`                             |
+|`writePin(pin, level)`|Set pin level, assuming it is an output                           | `(level) ? PORTB \|= (1<<2) : PORTB &= ~(1<<2)` | `(level) ? palSetLine(pin) : palClearLine(pin)` |
+|`readPin(pin)`        |Returns the level of the pin                                      | `_SFR_IO8(pin >> 4) & _BV(pin & 0xF)`          | `palReadLine(pin)`                              |
 
 ## Advanced Settings
 
 Each microcontroller can have multiple advanced settings regarding its GPIO. This abstraction layer does not limit the use of architecture-specific functions. Advanced users should consult the datasheet of their desired device and include any needed libraries. For AVR, the standard avr/io.h library is used; for STM32, the ChibiOS [PAL library](http://chibios.sourceforge.net/docs3/hal/group___p_a_l.html) is used.
-