Added C & MP interrupt example

examples/breakout_encoder_wheel/CMakeLists.txt

@@ -4,5 +4,6 @@ add_subdirectory(clock)
 add_subdirectory(colour_picker)
 add_subdirectory(encoder)
 add_subdirectory(gpio_pwm)
+add_subdirectory(interrupt)
 add_subdirectory(led_rainbow)
 add_subdirectory(stop_watch)

examples/breakout_encoder_wheel/README.md

@@ -3,6 +3,7 @@
 - [Function Examples](#function-examples)
   - [Buttons](#buttons)
   - [Encoder](#encoder)
+  - [Interrupt](#interrupt)
 - [LED Examples](#led-examples)
   - [LED Rainbow](#led-rainbow)
   - [Clock](#clock)
@@ -28,6 +29,12 @@ A demonstration of reading the 5 buttons on Encoder Wheel.
 A demonstration of reading the rotary dial of the Encoder Wheel breakout.
 
 
+### Interrupt
+[interrupt/interrupt.cpp](interrupt/interrupt.cpp)
+
+How to read the buttons and rotary dial of the Encoder Wheel breakout, only when an interrupt occurs.
+
+
 ## LED Examples
 
 ### LED Rainbow

examples/breakout_encoder_wheel/interrupt/CMakeLists.txt

@@ -0,0 +1,13 @@
+set(OUTPUT_NAME encoderwheel_interrupt)
+add_executable(${OUTPUT_NAME} interrupt.cpp)
+
+# Pull in pico libraries that we need
+target_link_libraries(${OUTPUT_NAME}
+  pico_stdlib
+  breakout_encoder_wheel
+)
+
+# enable usb output
+pico_enable_stdio_usb(${OUTPUT_NAME} 1)
+
+pico_add_extra_outputs(${OUTPUT_NAME})

examples/breakout_encoder_wheel/interrupt/interrupt.cpp

@@ -0,0 +1,84 @@
+#include <math.h>
+#include <string>
+#include "pimoroni_i2c.hpp"
+#include "breakout_encoder_wheel.hpp"
+#include "time.h"
+
+using namespace pimoroni;
+using namespace encoderwheel;
+
+/*
+How to read the buttons and rotary dial of the Encoder Wheel breakout, only when an interrupt occurs.
+*/
+
+// Constants
+const std::string BUTTON_NAMES[] = {"Up", "Down", "Left", "Right", "Centre"};
+
+// Create a new BreakoutEncoderWheel
+I2C i2c(BOARD::BREAKOUT_GARDEN);
+BreakoutEncoderWheel wheel(&i2c,
+                           BreakoutEncoderWheel::DEFAULT_IOE_I2C_ADDRESS,
+                           BreakoutEncoderWheel::DEFAULT_LED_I2C_ADDRESS,
+                           3);  // 3 for BG_BASE, 22 for EXPLORER_BASE, or 19 for some RP2040 boards
+// If wiring the breakout via the qw/st connector, use the below line instead
+// BreakoutEncoderWheel wheel(&i2c);
+
+// Variables
+bool last_pressed[NUM_BUTTONS] = {false, false, false, false, false};
+bool pressed[NUM_BUTTONS] = {false, false, false, false, false};
+int position = 0;
+float hue = 0.0f;
+
+
+int main() {
+  stdio_init_all();
+
+  // Attempt to initialise the encoder wheel
+  if(wheel.init()) {
+
+    // Set the first LED
+    wheel.clear();
+    wheel.set_hsv(position, hue, 1.0f, 1.0f);
+    wheel.show();
+
+    // Clear any left over interrupt from previous code
+    wheel.clear_interrupt_flag();
+
+    // Loop forever
+    while(true) {
+
+      // Check if the interrupt has fired
+      if(wheel.get_interrupt_flag()) {
+        wheel.clear_interrupt_flag();
+
+        // Read all of the encoder wheel's buttons
+        for(int b = 0 ; b < NUM_BUTTONS; b++) {
+          pressed[b] = wheel.pressed(b);
+          if(pressed[b] != last_pressed[b]) {
+            printf("%s %s\n", BUTTON_NAMES[b].c_str(), pressed[b] ? "Pressed" : "Released");
+          }
+          last_pressed[b] = pressed[b];
+        }
+
+        // The interrupt may have come from several sources,
+        // so check if it was a position change
+        int new_position = wheel.step();
+        if(new_position != position) {
+          // Record the new position (from 0 to 23)
+          position = new_position;
+          printf("Position = %d\n", position);
+
+          // Record a colour hue from 0.0 to 1.0
+          hue = fmodf(wheel.revolutions(), 1.0f);
+
+          // Set the LED at the new position to the new hue
+          wheel.clear();
+          wheel.set_hsv(position, hue, 1.0f, 1.0f);
+          wheel.show();
+        }
+      }
+    }
+  }
+
+  return 0;
+}

libraries/breakout_encoder_wheel/breakout_encoder_wheel.cpp

@@ -17,6 +17,12 @@ namespace encoderwheel {
       ioe.set_mode(SW_RIGHT, IOExpander::PIN_IN_PU);
       ioe.set_mode(SW_CENTRE, IOExpander::PIN_IN_PU);
 
+      ioe.set_pin_interrupt(SW_UP, true);
+      ioe.set_pin_interrupt(SW_DOWN, true);
+      ioe.set_pin_interrupt(SW_LEFT, true);
+      ioe.set_pin_interrupt(SW_RIGHT, true);
+      ioe.set_pin_interrupt(SW_CENTRE, true);
+
       led_ring.enable({
         0b00000000, 0b10111111,
         0b00111110, 0b00111110,

micropython/examples/breakout_encoder_wheel/README.md

@@ -3,6 +3,7 @@
 - [Function Examples](#function-examples)
   - [Buttons](#buttons)
   - [Encoder](#encoder)
+  - [Interrupt](#interrupt)
 - [LED Examples](#led-examples)
   - [LED Rainbow](#led-rainbow)
   - [Clock](#clock)
@@ -28,6 +29,12 @@ A demonstration of reading the 5 buttons on Encoder Wheel.
 A demonstration of reading the rotary dial of the Encoder Wheel breakout.
 
 
+### Interrupt
+[interrupt.py](interrupt.py)
+
+How to read the buttons and rotary dial of the Encoder Wheel breakout, only when an interrupt occurs.
+
+
 ## LED Examples
 
 ### LED Rainbow

micropython/examples/breakout_encoder_wheel/encoder.py

@@ -8,9 +8,6 @@
 Press Ctrl+C to stop the program.
 """
 
-PINS_BREAKOUT_GARDEN = {"sda": 4, "scl": 5}
-PINS_PICO_EXPLORER = {"sda": 20, "scl": 21}
-
 # Create a new BreakoutEncoderWheel
 i2c = PimoroniI2C(**BREAKOUT_GARDEN_I2C_PINS)
 wheel = BreakoutEncoderWheel(i2c)

micropython/examples/breakout_encoder_wheel/interrupt.py

@@ -0,0 +1,62 @@
+from pimoroni_i2c import PimoroniI2C
+from pimoroni import BREAKOUT_GARDEN_I2C_PINS  # or PICO_EXPLORER_I2C_PINS or HEADER_I2C_PINS
+from breakout_encoder_wheel import BreakoutEncoderWheel, NUM_BUTTONS
+
+"""
+How to read the buttons and rotary dial of the Encoder Wheel breakout, only when an interrupt occurs.
+
+Press Ctrl+C to stop the program.
+"""
+
+# Constants
+BUTTON_NAMES = ["Up", "Down", "Left", "Right", "Centre"]
+
+# Create a new BreakoutEncoderWheel with a pin on the Pico specified as an interrupt
+i2c = PimoroniI2C(**BREAKOUT_GARDEN_I2C_PINS)
+wheel = BreakoutEncoderWheel(i2c, interrupt=3)  # 3 for BG_BASE, 22 for EXPLORER_BASE, or 19 for some RP2040 boards
+# If wiring the breakout via the qw/st connector, use the below line instead
+# wheel = BreakoutEncoderWheel(i2c)
+
+# Variables
+last_pressed = [False] * NUM_BUTTONS
+pressed = [False] * NUM_BUTTONS
+position = 0
+hue = 0.0
+
+# Set the first LED
+wheel.clear()
+wheel.set_hsv(position, hue, 1.0, 1.0)
+wheel.show()
+
+# Clear any left over interrupt from previous code
+wheel.clear_interrupt_flag()
+
+# Loop forever
+while True:
+
+    # Check if the interrupt has fired
+    if wheel.get_interrupt_flag():
+        wheel.clear_interrupt_flag()
+
+        # Read all of the encoder wheel's buttons
+        for b in range(NUM_BUTTONS):
+            pressed[b] = wheel.pressed(b)
+            if pressed[b] != last_pressed[b]:
+                print(BUTTON_NAMES[b], "Pressed" if pressed[b] else "Released")
+            last_pressed[b] = pressed[b]
+
+        # The interrupt may have come from several sources,
+        # so check if it was a position change
+        new_position = wheel.step()
+        if new_position != position:
+            # Record the new position (from 0 to 23)
+            position = new_position
+            print("Position = ", position)
+
+            # Record a colour hue from 0.0 to 1.0
+            hue = wheel.revolutions() % 1.0
+
+            # Set the LED at the new position to the new hue
+            wheel.clear()
+            wheel.set_hsv(position, hue, 1.0, 1.0)
+            wheel.show()

micropython/modules/breakout_encoder_wheel/README.md

@@ -262,6 +262,8 @@ Here is the complete list of functions available on the `BreakoutEncoderWheel` c
 ```python
 BreakoutEncoderWheel(ioe_address=0x13, led_address=0x77, interrupt=PIN_UNUSED)
 set_ioe_address(address)
+get_interrupt_flag()
+clear_interrupt_flag()
 pressed(button)
 count()
 delta()
@@ -280,7 +282,7 @@ show()
 gpio_pin_mode(gpio)
 gpio_pin_mode(gpio, mode)
 gpio_pin_value(gpio)
-gpio_pin_value(gpio, value)
+gpio_pin_value(gpio, value, load=True, wait_for_load=False)
 gpio_pwm_load(wait_for_load=True)
 gpio_pwm_frequency(frequency, load=True, wait_for_load=True)
 ```