Initial skeleton

.gitignore

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+.vscode/
+build/
+
+*.pio.h

.gitmodules

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+[submodule "libs/pico-sdk"]
+	path = libs/pico-sdk
+	url = https://github.com/raspberrypi/pico-sdk.git

CMakeLists.txt

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+cmake_minimum_required(VERSION 3.13)
+
+include(libs/pico-sdk/pico_sdk_init.cmake)
+
+project(DonCon2040 VERSION 0.1.0)
+
+pico_sdk_init()
+
+set(CMAKE_C_STANDARD 11)
+set(CMAKE_CXX_STANDARD 17)
+
+add_compile_options(-Wall -Wextra -Werror)
+
+add_subdirectory(libs)
+
+file(GLOB ${PROJECT_NAME}_SOURCES src/*.cpp)
+
+add_executable(${PROJECT_NAME} ${${PROJECT_NAME}_SOURCES})
+
+target_include_directories(${PROJECT_NAME}
+                           PUBLIC ${CMAKE_CURRENT_LIST_DIR}/include)
+
+target_link_libraries(${PROJECT_NAME} PUBLIC pico_stdlib pio_ws2812)
+
+pico_enable_stdio_usb(${PROJECT_NAME} 1)
+pico_enable_stdio_uart(${PROJECT_NAME} 0)
+
+# create map/bin/hex/uf2 file in addition to ELF.
+pico_add_extra_outputs(${PROJECT_NAME})

LICENSE

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+MIT License
+
+Copyright (c) 2023 Frederik Walk
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the “Software”), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

libs/CMakeLists.txt

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+add_subdirectory(pio_ws2812)

libs/pico-sdk

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+Subproject commit 2ccab115de0d42d31d6611cca19ef0cd0d2ccaa7

libs/pio_ws2812/CMakeLists.txt

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+file(GLOB pio_ws2812_SOURCES src/*.c)
+
+add_library(pio_ws2812 STATIC ${pio_ws2812_SOURCES})
+
+pico_generate_pio_header(pio_ws2812 ${CMAKE_CURRENT_LIST_DIR}/src/ws2812.pio
+                         OUTPUT_DIR ${CMAKE_CURRENT_LIST_DIR}/generated)
+
+target_include_directories(
+  pio_ws2812
+  PUBLIC ${CMAKE_CURRENT_LIST_DIR}/include
+  PRIVATE ${CMAKE_CURRENT_LIST_DIR}/include/pio_ws2812
+  PRIVATE ${CMAKE_CURRENT_LIST_DIR}/generated)
+
+target_link_libraries(pio_ws2812 PUBLIC pico_stdlib hardware_pio)

libs/pio_ws2812/LICENSE

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+Copyright 2020 (c) 2020 Raspberry Pi (Trading) Ltd.
+
+Redistribution and use in source and binary forms, with or without modification, are permitted provided that the
+following conditions are met:
+
+1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following
+   disclaimer.
+
+2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following
+   disclaimer in the documentation and/or other materials provided with the distribution.
+
+3. Neither the name of the copyright holder nor the names of its contributors may be used to endorse or promote products
+   derived from this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
+INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

libs/pio_ws2812/include/pio_ws2812/ws2812.h

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+#ifndef _WS2812_H_
+#define _WS2812_h_
+
+#include "pico/stdlib.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+void ws2812_init(uint8_t pin, bool is_rgbw);
+
+uint32_t ws2812_rgb_to_u32pixel(uint8_t r, uint8_t g, uint8_t b);
+uint32_t ws2812_rgb_to_gamma_corrected_u32pixel(uint8_t r, uint8_t g, uint8_t b);
+
+void ws2812_put_pixel(uint32_t pixel_grb);
+void ws2812_put_frame(uint32_t *frame, size_t length);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif // _WS2812_H_

libs/pio_ws2812/src/ws2812.c

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+/**
+ * Copyright (c) 2020 Raspberry Pi (Trading) Ltd.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include "ws2812.h"
+#include "ws2812.pio.h"
+
+#include "hardware/clocks.h"
+#include "hardware/pio.h"
+
+static const uint8_t gamma_correct[] = {
+    0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,
+    0,   0,   0,   0,   0,   0,   1,   1,   1,   1,   1,   1,   1,   1,   1,   1,   1,   1,   1,   2,   2,   2,
+    2,   2,   2,   2,   2,   3,   3,   3,   3,   3,   3,   3,   4,   4,   4,   4,   4,   5,   5,   5,   5,   6,
+    6,   6,   6,   7,   7,   7,   7,   8,   8,   8,   9,   9,   9,   10,  10,  10,  11,  11,  11,  12,  12,  13,
+    13,  13,  14,  14,  15,  15,  16,  16,  17,  17,  18,  18,  19,  19,  20,  20,  21,  21,  22,  22,  23,  24,
+    24,  25,  25,  26,  27,  27,  28,  29,  29,  30,  31,  32,  32,  33,  34,  35,  35,  36,  37,  38,  39,  39,
+    40,  41,  42,  43,  44,  45,  46,  47,  48,  49,  50,  50,  51,  52,  54,  55,  56,  57,  58,  59,  60,  61,
+    62,  63,  64,  66,  67,  68,  69,  70,  72,  73,  74,  75,  77,  78,  79,  81,  82,  83,  85,  86,  87,  89,
+    90,  92,  93,  95,  96,  98,  99,  101, 102, 104, 105, 107, 109, 110, 112, 114, 115, 117, 119, 120, 122, 124,
+    126, 127, 129, 131, 133, 135, 137, 138, 140, 142, 144, 146, 148, 150, 152, 154, 156, 158, 160, 162, 164, 167,
+    169, 171, 173, 175, 177, 180, 182, 184, 186, 189, 191, 193, 196, 198, 200, 203, 205, 208, 210, 213, 215, 218,
+    220, 223, 225, 228, 231, 233, 236, 239, 241, 244, 247, 249, 252, 255};
+
+void ws2812_init(uint8_t pin, bool is_rgbw) {
+    PIO pio = pio0;
+    int sm = 0;
+    uint offset = pio_add_program(pio, &ws2812_program);
+
+    ws2812_program_init(pio, sm, offset, pin, 800000, is_rgbw);
+}
+
+uint32_t ws2812_rgb_to_u32pixel(uint8_t r, uint8_t g, uint8_t b) {
+    return ((uint32_t)(r) << 8) | ((uint32_t)(g) << 16) | (uint32_t)(b);
+}
+
+uint32_t ws2812_rgb_to_gamma_corrected_u32pixel(uint8_t r, uint8_t g, uint8_t b) {
+    return ((uint32_t)(gamma_correct[r]) << 8) | ((uint32_t)(gamma_correct[g]) << 16) | (uint32_t)(gamma_correct[b]);
+}
+
+void ws2812_put_pixel(uint32_t pixel_grb) { pio_sm_put_blocking(pio0, 0, pixel_grb << 8u); }
+
+void ws2812_put_frame(uint32_t *frame, size_t length) {
+    for (size_t i = 0; i < length; ++i) {
+        ws2812_put_pixel(frame[i]);
+    }
+    sleep_us(60);
+}

libs/pio_ws2812/src/ws2812.pio

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+;
+; Copyright (c) 2020 Raspberry Pi (Trading) Ltd.
+;
+; SPDX-License-Identifier: BSD-3-Clause
+;
+
+.program ws2812
+.side_set 1
+
+.define public T1 2
+.define public T2 5
+.define public T3 3
+
+.lang_opt python sideset_init = pico.PIO.OUT_HIGH
+.lang_opt python out_init     = pico.PIO.OUT_HIGH
+.lang_opt python out_shiftdir = 1
+
+.wrap_target
+bitloop:
+    out x, 1       side 0 [T3 - 1] ; Side-set still takes place when instruction stalls
+    jmp !x do_zero side 1 [T1 - 1] ; Branch on the bit we shifted out. Positive pulse
+do_one:
+    jmp  bitloop   side 1 [T2 - 1] ; Continue driving high, for a long pulse
+do_zero:
+    nop            side 0 [T2 - 1] ; Or drive low, for a short pulse
+.wrap
+
+% c-sdk {
+#include "hardware/clocks.h"
+
+static inline void ws2812_program_init(PIO pio, uint sm, uint offset, uint pin, float freq, bool rgbw) {
+
+    pio_gpio_init(pio, pin);
+    pio_sm_set_consecutive_pindirs(pio, sm, pin, 1, true);
+
+    pio_sm_config c = ws2812_program_get_default_config(offset);
+    sm_config_set_sideset_pins(&c, pin);
+    sm_config_set_out_shift(&c, false, true, rgbw ? 32 : 24);
+    sm_config_set_fifo_join(&c, PIO_FIFO_JOIN_TX);
+
+    int cycles_per_bit = ws2812_T1 + ws2812_T2 + ws2812_T3;
+    float div = clock_get_hz(clk_sys) / (freq * cycles_per_bit);
+    sm_config_set_clkdiv(&c, div);
+
+    pio_sm_init(pio, sm, offset, &c);
+    pio_sm_set_enabled(pio, sm, true);
+}
+%}

src/main.cpp

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+#include "pico/stdlib.h"
+
+#include <stdio.h>
+
+int main() {
+    stdio_init_all();
+
+    while (true) {
+        sleep_ms(1);
+    }
+}