From ff801b378372ae30a8e402c4404ca8aff2b70018 Mon Sep 17 00:00:00 2001
From: Archie Hilton <archie.hilton1@gmail.com>
Date: Tue, 2 Jul 2024 21:26:26 +0100
Subject: [PATCH] Add rotary encoder control

---
 .ccls              |  2 --
 .clangd            |  5 +---
 src/CMakeLists.txt |  3 ++-
 src/main.cc        | 58 ++++++++++++++++++++++++++++++++++------------
 4 files changed, 46 insertions(+), 22 deletions(-)
 delete mode 100644 .ccls

diff --git a/.ccls b/.ccls
deleted file mode 100644
index 117fa70..0000000
--- a/.ccls
+++ /dev/null
@@ -1,2 +0,0 @@
-%compile_commands.json
---sysroot=/usr/arm-none-eabi/
diff --git a/.clangd b/.clangd
index bf0f570..77d1a1d 100755
--- a/.clangd
+++ b/.clangd
@@ -1,5 +1,2 @@
 CompileFlags:
-  #Add: [--query-driver=/usr/bin/arm-none-eabi-g++]
-  Compiler: /usr/bin/arm-none-eabi-g++
-
-
+  Compiler: /usr/toolchains/arm-none-eabi/13/bin/arm-none-eabi-g++
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index d78d2dc..c77a991 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -2,7 +2,8 @@ add_executable(main
   main.cc
   )
 
-target_link_libraries(main pico_stdlib hardware_i2c hardware_uart)
+target_link_libraries(main pico_stdlib hardware_i2c hardware_uart hardware_irq
+  hardware_gpio)
 
 pico_enable_stdio_uart(main 0)
 pico_enable_stdio_usb(main 1)
diff --git a/src/main.cc b/src/main.cc
index 8bb977f..8ecad84 100644
--- a/src/main.cc
+++ b/src/main.cc
@@ -2,11 +2,14 @@
 
 #include "hardware/gpio.h"
 #include "hardware/i2c.h"
+#include "pico/time.h"
+#include "pico/types.h"
+
 #include <pico/stdlib.h>
 #include <pico/stdio.h>
 
-#include <stdio.h>
-#include <string.h>
+#include <cstdio>
+#include <cstring>
 
 #define ADDR 0x3c
 
@@ -45,6 +48,30 @@ static uint32_t charset[127] = {
   0x7c90904c, 0x90b0d090, 0x81816618, 0x00ff0000, 0x81816618, 0x10081008, INVALID_CH, 
 };
 
+static uint8_t encoder_pos = 0;
+
+void irq_callback(uint gpio, uint32_t events) {
+  static absolute_time_t time_last = get_absolute_time();
+  static uint8_t prev = 0;
+  if (gpio == 19)   {
+    absolute_time_t time_now = get_absolute_time();
+    if (time_now - time_last < 1000) return;
+
+    time_last = time_now;
+    uint8_t twenty = gpio_get(20);
+    if (twenty != prev) {
+      if (twenty == 0) {
+        if (events & GPIO_IRQ_EDGE_RISE) encoder_pos++;
+        else encoder_pos--;
+      } else {
+        if (events & GPIO_IRQ_EDGE_RISE) encoder_pos--;
+        else encoder_pos++;
+      }
+      prev = twenty;
+    }
+  }
+}
+
 int main(void) {
   stdio_init_all();
 
@@ -53,6 +80,12 @@ int main(void) {
   gpio_init(25);
   gpio_set_dir(25, GPIO_OUT);
 
+  gpio_init(19);
+  gpio_init(20);
+  gpio_set_dir(19, GPIO_IN);
+  gpio_set_dir(20, GPIO_IN);
+
+  gpio_set_irq_enabled_with_callback(19, GPIO_IRQ_EDGE_FALL | GPIO_IRQ_EDGE_RISE, true, &irq_callback);
 
   i2c_init(i2c0, 400000);
   gpio_init(0);
@@ -65,15 +98,12 @@ int main(void) {
   busy_wait_ms(100);
 
   disp.fill(0);
-  disp.puts(0, 0, "Hello, World!");
-  disp.flush();
   while (true) {
-    /*
-    gpio_put(25, false);
-    busy_wait_ms(failure ? 50 : 500);
-    gpio_put(25, true);
-    busy_wait_ms(failure ? 50 : 500);
-    */
+    disp.fill(0);
+    disp.put_char(4, 0, (encoder_pos & 0xF) >= 0xA ? (encoder_pos&0xf) - 0xA + 'A':(encoder_pos&0xf)+'0');
+    disp.put_char(0, 0, ((encoder_pos>>4) & 0xF) >= 0xA? ((encoder_pos>>4) & 0xf) - 0xA + 'A':((encoder_pos>>4)&0xf)+'0');
+    disp.flush();
+    busy_wait_ms(50);
   }
 
   return 0;
@@ -84,9 +114,9 @@ static void write_cmd(uint8_t cmd) {
 
   if (i2c_write_timeout_us(i2c0, ADDR, buf, 2, false, 1000000) < 0) {
     failure = true;
-    printf("TX fail\n");
+    std::printf("TX fail\n");
   } else {
-    printf("TX succ\n");
+    std::printf("TX succ\n");
   }
 }
 
@@ -168,9 +198,7 @@ void ssd1306::flush() {
 }
 
 void ssd1306::put_char(uint8_t row, uint8_t col, char c) {
-  if (row % 4 != 0) return;
-
-  memcpy(&m_display_buffer[1 + (row + (128*col))], &charset[c-1], 4);
+  memcpy(m_display_buffer+(1+(row + (128*col))), &charset[c-1], 4);
 }
 
 void ssd1306::puts(uint8_t row, uint8_t col, const char *str) {