draw version and repo info on oled

.gitmodules

@@ -4,3 +4,6 @@
 [submodule "firmware/pico-sdk"]
 	path = firmware/pico-sdk
 	url = https://github.com/raspberrypi/pico-sdk
+[submodule "firmware/pico-ssd1306"]
+	path = firmware/pico-ssd1306
+	url = https://github.com/daschr/pico-ssd1306/

README.md

@@ -11,6 +11,7 @@ Check out the [Dispensy documentation](https://drinkrobotics.github.io/dispensy/
 ## License
 
 This hardware of this project is licensed under the [CERN Open Hardware Licence Version 2 - Strongly Reciprocal (CERN-OHL-S-2.0+)](https://ohwr.org/cern_ohl_s_v2.txt) or any later version.
+The SSD1306 footprint is from [KiCAD Rookie](https://kicadrookie.blogspot.com/2022/06/ssd1306-i2c-096in-oled-display-kicad_86.html).
 
 The docs are built using [mdbook](https://github.com/rust-lang/mdBook), licensed as `MPL-2.0`.
 The PCB SVG files in the documentation are displayed using [svg-pan-zoom](https://github.com/bumbu/svg-pan-zoom), licensed as `BSD-2-Clause`.
@@ -45,6 +46,8 @@ The firmware of this project is licensed as GPLv3.
 I initially adapted it from my own [Trackball](https://git.xythobuz.de/thomas/Trackball) and [Volcano Remote](https://git.xythobuz.de/thomas/sb-py) projects.
 It uses the [Pi Pico SDK](https://github.com/raspberrypi/pico-sdk), licensed as BSD 3-clause, and therefore also [TinyUSB](https://github.com/hathach/tinyusb), licensed under the MIT license.
 Some code is adapted from the TinyUSB examples.
+To control the OLED display, [pico-ssd1306](https://github.com/daschr/pico-ssd1306) is used, licensed under the MIT license.
+Repo metadata is embedded into the project using [cmake-git-version-tracking](https://github.com/andrew-hardin/cmake-git-version-tracking), licensed under the MIT license.
 
     This program is free software: you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by

firmware/CMakeLists.txt

@@ -40,9 +40,12 @@ target_sources(dispensy PUBLIC
     ${CMAKE_CURRENT_LIST_DIR}/src/buttons.c
     ${CMAKE_CURRENT_LIST_DIR}/src/lcd.c
     ${CMAKE_CURRENT_LIST_DIR}/src/ring.c
+
+    ${CMAKE_CURRENT_LIST_DIR}/pico-ssd1306/ssd1306.c
 )
 
 target_include_directories(dispensy PUBLIC ${CMAKE_CURRENT_LIST_DIR}/include)
+target_include_directories(dispensy PUBLIC ${CMAKE_CURRENT_LIST_DIR}/pico-ssd1306)
 
 # enable generous warnings
 target_compile_options(dispensy PUBLIC
@@ -61,6 +64,14 @@ set_source_files_properties(pico-sdk/lib/btstack/src/classic/goep_client.c PROPE
 set_source_files_properties(pico-sdk/lib/btstack/src/classic/goep_server.c PROPERTIES COMPILE_FLAGS -Wno-unused-parameter)
 set_source_files_properties(pico-sdk/src/rp2_common/hardware_flash/flash.c PROPERTIES COMPILE_FLAGS -Wno-shadow)
 
+# repo meta data
+include(FetchContent)
+FetchContent_Declare(cmake_git_version_tracking
+    GIT_REPOSITORY https://github.com/andrew-hardin/cmake-git-version-tracking.git
+    GIT_TAG 6c0cb87edd029ddfb403a8e24577c144a03605a6
+)
+FetchContent_MakeAvailable(cmake_git_version_tracking)
+
 # pull in common dependencies
 target_link_libraries(dispensy
     pico_stdlib
@@ -69,7 +80,8 @@ target_link_libraries(dispensy
     tinyusb_board
     hardware_adc
     hardware_gpio
-    hardware_pwm
+    hardware_i2c
+    cmake_git_version_tracking
 )
 
 # fix for Errata RP2040-E5 (the fix requires use of GPIO 15)

firmware/include/config.h

@@ -19,8 +19,8 @@
 #ifndef __CONFIG_H__
 #define __CONFIG_H__
 
-#define APP_VERSION_MAJOR 0
-#define APP_VERSION_MINOR 1
+#define VERSION_MAJOR 0
+#define VERSION_MINOR 1
 
 #define WATCHDOG_PERIOD_MS 10
 
@@ -30,4 +30,11 @@
 //#define DISABLE_CDC_DTR_CHECK
 #define DEBOUNCE_DELAY_MS 5
 
+// ----------------------------------------------------------------------------
+
+#define STR_HELPER(x) #x
+#define STR(x) STR_HELPER(x)
+
+#define VERSION_STR "V" STR(VERSION_MAJOR) "." STR(VERSION_MINOR)
+
 #endif // __CONFIG_H__

firmware/include/lcd.h

@@ -22,6 +22,10 @@
 #define LCD_WIDTH 128
 #define LCD_HEIGHT 64
 
+#define FONT_HEIGHT 8
+#define FONT_WIDTH 5
+
 void lcd_init(void);
+void lcd_splash(void);
 
 #endif // __LCD_H__

firmware/pico-ssd1306

@@ -0,0 +1 @@
+Subproject commit 8467f5b06ebd7bfa7b53e4ebc83dfdc6f396e4eb

firmware/src/lcd.c

@@ -16,9 +16,62 @@
  * See <http://www.gnu.org/licenses/>.
  */
 
+#include <string.h>
+
+#include "hardware/i2c.h"
+#include "ssd1306.h"
+#include "git.h"
+
 #include "config.h"
 #include "log.h"
 #include "lcd.h"
 
+#define LCD_I2C_ADDR 0x3C
+
+static i2c_inst_t *gpio_inst_i2c = i2c1;
+static const uint gpio_num_i2c[2] = { 14, 15 };
+
+static ssd1306_t lcd = {0};
+
 void lcd_init(void) {
+    i2c_init(gpio_inst_i2c, 2UL * 1000UL * 1000UL);
+
+    for (uint i = 0; i < sizeof(gpio_num_i2c) / sizeof(gpio_num_i2c[0]); i++) {
+        gpio_set_function(gpio_num_i2c[i], GPIO_FUNC_I2C);
+        gpio_pull_up(gpio_num_i2c[i]);
+    }
+
+    ssd1306_init(&lcd, LCD_WIDTH, LCD_HEIGHT, LCD_I2C_ADDR, gpio_inst_i2c);
+}
+
+void lcd_splash(void) {
+    ssd1306_clear(&lcd);
+
+    ssd1306_draw_string(&lcd, 0, 0, 2,
+                        "Dispensy");
+
+    ssd1306_draw_string(&lcd, 0, FONT_HEIGHT * 2 + 1, 1,
+                        "Release: " VERSION_STR);
+
+    ssd1306_draw_string(&lcd, 0, FONT_HEIGHT * 2 + 1 + FONT_HEIGHT + 1, 1,
+                        __DATE__ " " __TIME__);
+
+    if (git_IsPopulated()) {
+        const char *hash = git_CommitSHA1();
+        char short_hash[6 + 7 + 1] = {0};
+        memcpy(short_hash, "Hash: ", 6);
+        memcpy(short_hash + 6, hash, 7);
+        ssd1306_draw_string(&lcd, 0, FONT_HEIGHT * 2 + 1 + (FONT_HEIGHT + 1) * 2, 1,
+                            short_hash);
+
+        if (git_AnyUncommittedChanges()) {
+            ssd1306_draw_string(&lcd, 0, FONT_HEIGHT * 2 + 1 + (FONT_HEIGHT + 1) * 3, 1,
+                                "Repo has changes!");
+        }
+    } else {
+        ssd1306_draw_string(&lcd, 0, FONT_HEIGHT * 2 + 1 + (FONT_HEIGHT + 1) * 2, 1,
+                            "No Git Repo");
+    }
+
+    ssd1306_show(&lcd);
 }

firmware/src/main.c

@@ -48,6 +48,7 @@ int main(void) {
 
     buttons_init();
     lcd_init();
+    lcd_splash();
 
     debug("go");