PicoDVI/software/apps/mandelbrot/main.c

107 wiersze
2.7 KiB
C

#include <stdio.h>
#include <stdlib.h>
#include "pico/stdlib.h"
#include "pico/multicore.h"
#include "hardware/clocks.h"
#include "hardware/gpio.h"
#include "hardware/irq.h"
#include "hardware/sync.h"
#include "hardware/vreg.h"
#include "pico/sem.h"
#include "dvi.h"
#include "dvi_serialiser.h"
#include "common_dvi_pin_configs.h"
#include "sprite.h"
// TMDS bit clock 252 MHz
// DVDD 1.2V (1.1V seems ok too)
#define FRAME_WIDTH 320
#define FRAME_HEIGHT 240
#define VREG_VSEL VREG_VOLTAGE_1_20
#define DVI_TIMING dvi_timing_640x480p_60hz
#define LED_PIN 16
struct dvi_inst dvi0;
uint16_t framebuf[FRAME_WIDTH * FRAME_HEIGHT];
void core1_main() {
dvi_register_irqs_this_core(&dvi0, DMA_IRQ_0);
dvi_start(&dvi0);
dvi_scanbuf_main_16bpp(&dvi0);
__builtin_unreachable();
}
void core1_scanline_callback() {
// Discard any scanline pointers passed back
uint16_t *bufptr;
while (queue_try_remove_u32(&dvi0.q_colour_free, &bufptr))
;
// // Note first two scanlines are pushed before DVI start
static uint scanline = 2;
bufptr = &framebuf[FRAME_WIDTH * scanline];
queue_add_blocking_u32(&dvi0.q_colour_valid, &bufptr);
scanline = (scanline + 1) % FRAME_HEIGHT;
}
int main() {
vreg_set_voltage(VREG_VSEL);
sleep_ms(10);
#ifdef RUN_FROM_CRYSTAL
set_sys_clock_khz(12000, true);
#else
// Run system at TMDS bit clock
set_sys_clock_khz(DVI_TIMING.bit_clk_khz, true);
#endif
setup_default_uart();
gpio_init(LED_PIN);
gpio_set_dir(LED_PIN, GPIO_OUT);
printf("Configuring DVI\n");
dvi0.timing = &DVI_TIMING;
dvi0.ser_cfg = DVI_DEFAULT_SERIAL_CONFIG;
dvi0.scanline_callback = core1_scanline_callback;
dvi_init(&dvi0, next_striped_spin_lock_num(), next_striped_spin_lock_num());
// Once we've given core 1 the framebuffer, it will just keep on displaying
// it without any intervention from core 0
sprite_fill16(framebuf, 0xffff, FRAME_WIDTH * FRAME_HEIGHT);
uint16_t *bufptr = framebuf;
queue_add_blocking_u32(&dvi0.q_colour_valid, &bufptr);
bufptr += FRAME_WIDTH;
queue_add_blocking_u32(&dvi0.q_colour_valid, &bufptr);
printf("Core 1 start\n");
multicore_launch_core1(core1_main);
printf("Start rendering\n");
for (int y = 0; y < FRAME_HEIGHT; ++y) {
for (int x = 0; x < FRAME_WIDTH; ++x) {
const float scale = FRAME_HEIGHT / 2;
float cr = ((float)x - FRAME_WIDTH / 2) / scale - 0.5f;
float ci = ((float)y - FRAME_HEIGHT / 2) / scale;
float zr = cr;
float zi = ci;
int iters;
const int max_iters = 255;
for (iters = 0; iters < max_iters; ++iters) {
if (zr * zr + zi * zi > 4.f)
break;
float zrtemp = zr * zr - zi * zi + cr;
zi = 2.f * zr * zi + ci;
zr = zrtemp;
}
framebuf[y * FRAME_WIDTH + x] = ((max_iters - iters) >> 2) * 0x41 >> 1;
}
}
while (1)
__wfe();
__builtin_unreachable();
}