diff options
-rw-r--r-- | .gitignore | 2 | ||||
-rw-r--r-- | CMakeLists.txt | 25 | ||||
-rw-r--r-- | main.c | 49 | ||||
-rw-r--r-- | ws2812.pio | 85 |
4 files changed, 161 insertions, 0 deletions
diff --git a/.gitignore b/.gitignore new file mode 100644 index 0000000..01e12f3 --- /dev/null +++ b/.gitignore @@ -0,0 +1,2 @@ +generated/ +build/ diff --git a/CMakeLists.txt b/CMakeLists.txt new file mode 100644 index 0000000..ec8beae --- /dev/null +++ b/CMakeLists.txt @@ -0,0 +1,25 @@ +cmake_minimum_required(VERSION 3.13) +include(/home/dwlr/projects/current/rp2040/pico-sdk/pico_sdk_init.cmake) + +pico_sdk_init() +project(eeprom2blk) +enable_language(C CXX ASM) + +add_executable(eeprom2blk main.c) + +set_source_files_properties(main.c PROPERTIES + COMPILE_FLAGS -Wall -Wextra -pedantic + C_STANDARD 90 +) + +file(MAKE_DIRECTORY ${CMAKE_CURRENT_LIST_DIR}/generated) +pico_generate_pio_header(eeprom2blk ${CMAKE_CURRENT_LIST_DIR}/ws2812.pio OUTPUT_DIR ${CMAKE_CURRENT_LIST_DIR}/generated) + +target_link_libraries(eeprom2blk pico_stdlib hardware_pio hardware_dma) + +# change default stdout +pico_enable_stdio_usb(eeprom2blk 1) +pico_enable_stdio_uart(eeprom2blk 0) + +# create map/bin/hex/uf2 file in addition to ELF. +pico_add_extra_outputs(eeprom2blk) @@ -0,0 +1,49 @@ +#include <stdio.h> +#include <stdlib.h> +#include <stdbool.h> +#include <stdint.h> +#include <string.h> +#include <assert.h> + +#include "pico/stdlib.h" +#include "hardware/gpio.h" +#include "hardware/pio.h" +#include "hardware/clocks.h" + +#include "ws2812.pio.h" + + +#define PIN_RGB 16 + + +int main(void) +{ + stdio_init_all(); + + gpio_init(PIN_RGB); + gpio_set_dir(PIN_RGB, GPIO_OUT); + gpio_put(PIN_RGB, 1); + + PIO pio = pio0; + int sm = 0; // XXX: ??? + uint32_t offset = pio_add_program(pio, &ws2812_program); + + ws2812_program_init(pio, sm, offset, PIN_RGB, 800000, false); + + uint32_t col = 0; + pio_sm_put_blocking(pio0, 0, col << 8u); + + sleep_ms(1000); + + col = 0x0000FF; + printf("Hell, world...\n"); + while(1) + { + pio_sm_put_blocking(pio0, 0, col); + col = col << 8u; + if(!col) col = 0x0000FF; + sleep_ms(250); + } + + return 0; +} diff --git a/ws2812.pio b/ws2812.pio new file mode 100644 index 0000000..3c31fd6 --- /dev/null +++ b/ws2812.pio @@ -0,0 +1,85 @@ +; +; 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); +} +%} + +.program ws2812_parallel + +.define public T1 2 +.define public T2 5 +.define public T3 3 + +.wrap_target + out x, 32 + mov pins, !null [T1-1] + mov pins, x [T2-1] + mov pins, null [T3-2] +.wrap + +% c-sdk { +#include "hardware/clocks.h" + +static inline void ws2812_parallel_program_init(PIO pio, uint sm, uint offset, uint pin_base, uint pin_count, float freq) { + for(uint i=pin_base; i<pin_base+pin_count; i++) { + pio_gpio_init(pio, i); + } + pio_sm_set_consecutive_pindirs(pio, sm, pin_base, pin_count, true); + + pio_sm_config c = ws2812_parallel_program_get_default_config(offset); + sm_config_set_out_shift(&c, true, true, 32); + sm_config_set_out_pins(&c, pin_base, pin_count); + sm_config_set_set_pins(&c, pin_base, pin_count); + sm_config_set_fifo_join(&c, PIO_FIFO_JOIN_TX); + + int cycles_per_bit = ws2812_parallel_T1 + ws2812_parallel_T2 + ws2812_parallel_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); +} +%} |