mirrors
/
pimoroni-pico
mirror of https://github.com/pimoroni/pimoroni-pico.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity
pimoroni-pico/drivers/st7789/st7789.cpp

286 lines
8.3 KiB
C++
Raw Blame History

#include "st7789.hpp"
#include <cstdlib>
#include <math.h>
#include "hardware/dma.h"
#include "hardware/pwm.h"
namespace pimoroni {
uint8_t madctl;
uint16_t caset[2] = {0, 0};
uint16_t raset[2] = {0, 0};
enum MADCTL : uint8_t {
ROW_ORDER = 0b10000000,
COL_ORDER = 0b01000000,
SWAP_XY = 0b00100000, // AKA "MV"
SCAN_ORDER = 0b00010000,
RGB = 0b00001000,
HORIZ_ORDER = 0b00000100
};
#define ROT_240_240_0 0
#define ROT_240_240_90 MADCTL::SWAP_XY | MADCTL::HORIZ_ORDER | MADCTL::COL_ORDER
#define ROT_240_240_180 MADCTL::SCAN_ORDER | MADCTL::HORIZ_ORDER | MADCTL::COL_ORDER | MADCTL::ROW_ORDER
#define ROT_240_240_270 MADCTL::SWAP_XY | MADCTL::HORIZ_ORDER | MADCTL::ROW_ORDER
enum reg {
SWRESET = 0x01,
TEOFF = 0x34,
TEON = 0x35,
MADCTL = 0x36,
COLMOD = 0x3A,
GCTRL = 0xB7,
VCOMS = 0xBB,
LCMCTRL = 0xC0,
VDVVRHEN = 0xC2,
VRHS = 0xC3,
VDVS = 0xC4,
FRCTRL2 = 0xC6,
PWCTRL1 = 0xD0,
PORCTRL = 0xB2,
GMCTRP1 = 0xE0,
GMCTRN1 = 0xE1,
INVOFF = 0x20,
SLPOUT = 0x11,
DISPON = 0x29,
GAMSET = 0x26,
DISPOFF = 0x28,
RAMWR = 0x2C,
INVON = 0x21,
CASET = 0x2A,
RASET = 0x2B,
PWMFRSEL = 0xCC
};
void ST7789::init(bool auto_init_sequence, bool round, uint32_t spi_baud) {
// configure spi interface and pins
spi_init(spi, spi_baud);
gpio_set_function(dc, GPIO_FUNC_SIO);
gpio_set_dir(dc, GPIO_OUT);
gpio_set_function(cs, GPIO_FUNC_SIO);
gpio_set_dir(cs, GPIO_OUT);
gpio_set_function(sck, GPIO_FUNC_SPI);
gpio_set_function(mosi, GPIO_FUNC_SPI);
if(miso != PIN_UNUSED) {
gpio_set_function(miso, GPIO_FUNC_SPI);
}
// if supported by the display then the vsync pin is
// toggled high during vertical blanking period
if(vsync != PIN_UNUSED) {
gpio_set_function(vsync, GPIO_FUNC_SIO);
gpio_set_dir(vsync, GPIO_IN);
gpio_set_pulls(vsync, false, true);
}
// if a backlight pin is provided then set it up for
// pwm control
if(bl != PIN_UNUSED) {
pwm_config cfg = pwm_get_default_config();
pwm_set_wrap(pwm_gpio_to_slice_num(bl), 65535);
pwm_init(pwm_gpio_to_slice_num(bl), &cfg, true);
gpio_set_function(bl, GPIO_FUNC_PWM);
set_backlight(0); // Turn backlight off initially to avoid nasty surprises
}
// if auto_init_sequence then send initialisation sequence
// for our standard displays based on the width and height
if(auto_init_sequence) {
command(reg::SWRESET);
sleep_ms(150);
command(reg::TEON); // enable frame sync signal if used
command(reg::COLMOD, 1, "\x05"); // 16 bits per pixel
if(width == 240 && height == 240) {
command(reg::PORCTRL, 5, "\x0c\x0c\x00\x33\x33");
command(reg::GCTRL, 1, "\x14");
command(reg::VCOMS, 1, "\x37");
command(reg::LCMCTRL, 1, "\x2c");
command(reg::VDVVRHEN, 1, "\x01");
command(reg::VRHS, 1, "\x12");
command(reg::VDVS, 1, "\x20");
command(reg::PWCTRL1, 2, "\xa4\xa1");
command(reg::FRCTRL2, 1, "\x0f");
command(reg::GMCTRP1, 14, "\xD0\x04\x0D\x11\x13\x2B\x3F\x54\x4C\x18\x0D\x0B\x1F\x23");
command(reg::GMCTRN1, 14, "\xD0\x04\x0C\x11\x13\x2C\x3F\x44\x51\x2F\x1F\x1F\x20\x23");
}
if(width == 320 && height == 240) {
command(reg::PORCTRL, 5, "\x0c\x0c\x00\x33\x33");
command(reg::GCTRL, 1, "\x35");
command(reg::VCOMS, 1, "\x1f");
command(reg::LCMCTRL, 1, "\x2c");
command(reg::VDVVRHEN, 1, "\x01");
command(reg::VRHS, 1, "\x12");
command(reg::VDVS, 1, "\x20");
command(reg::FRCTRL2, 1, "\x0f");
command(reg::PWCTRL1, 2, "\xa4\xa1");
command(0xd6, 1, "\xa1"); // ???
command(reg::GMCTRP1, 14, "\xD0\x08\x11\x08\x0C\x15\x39\x33\x50\x36\x13\x14\x29\x2D");
command(reg::GMCTRN1, 14, "\xD0\x08\x10\x08\x06\x06\x39\x44\x51\x0B\x16\x14\x2F\x31");
}
command(reg::INVON); // set inversion mode
command(reg::SLPOUT); // leave sleep mode
command(reg::DISPON); // turn display on
sleep_ms(100);
// setup correct addressing window
if(width == 240 && height == 240) {
caset[0] = 0;
caset[1] = 239;
raset[0] = round ? 40 : 0;
raset[1] = round ? 279 : 239;
madctl = MADCTL::HORIZ_ORDER;
}
if(width == 240 && height == 135) {
caset[0] = 40; // 240 cols
caset[1] = 279;
raset[0] = 53; // 135 rows
raset[1] = 187;
madctl = MADCTL::COL_ORDER | MADCTL::SWAP_XY | MADCTL::SCAN_ORDER;
}
if(width == 135 && height == 240) {
caset[0] = 52; // 135 cols
caset[1] = 186;
raset[0] = 40; // 240 rows
raset[1] = 279;
madctl = 0;
}
if(width == 320 && height == 240) {
caset[0] = 0;
caset[1] = 319;
raset[0] = 0;
raset[1] = 239;
madctl = 0x70;
}
// Byte swap the 16bit rows/cols values
caset[0] = __builtin_bswap16(caset[0]);
caset[1] = __builtin_bswap16(caset[1]);
raset[0] = __builtin_bswap16(raset[0]);
raset[1] = __builtin_bswap16(raset[1]);
command(reg::CASET, 4, (char *)caset);
command(reg::RASET, 4, (char *)raset);
command(reg::MADCTL, 1, (char *)&madctl);
if(bl != PIN_UNUSED) {
update(); // Send the new buffer to the display to clear any previous content
sleep_ms(50); // Wait for the update to apply
set_backlight(255); // Turn backlight on now surprises have passed
}
}
// the dma transfer works but without vsync it's not that useful as you could
// be updating the framebuffer during transfer...
//
// this could be avoided by creating another buffer to draw into and flip
// buffers (but costs another ~100kb of ram)
//
// it's probably not worth it for this particular usecase but will consider it
// some more...
// setup spi for 16-bit transfers
// spi_set_format(spi, 16, SPI_CPOL_0, SPI_CPHA_0, SPI_MSB_FIRST);
// initialise dma channel for transmitting pixel data to screen
// dma_channel = dma_claim_unused_channel(true);
// dma_channel_config config = dma_channel_get_default_config(dma_channel);
// channel_config_set_transfer_data_size(&config, DMA_SIZE_16);
// channel_config_set_dreq(&config, spi_get_index(spi) ? DREQ_SPI1_TX : DREQ_SPI0_TX);
// dma_channel_configure(
// dma_channel, &config, &spi_get_hw(spi)->dr, frame_buffer, width * height, false);
}
spi_inst_t* ST7789::get_spi() const {
return spi;
}
uint ST7789::get_cs() const {
return cs;
}
uint ST7789::get_dc() const {
return dc;
}
uint ST7789::get_sck() const {
return sck;
}
uint ST7789::get_mosi() const {
return mosi;
}
uint ST7789::get_bl() const {
return bl;
}
void ST7789::command(uint8_t command, size_t len, const char *data) {
//dma_channel_wait_for_finish_blocking(dma_channel);
gpio_put(cs, 0);
gpio_put(dc, 0); // command mode
spi_write_blocking(spi, &command, 1);
if(data) {
gpio_put(dc, 1); // data mode
spi_write_blocking(spi, (const uint8_t*)data, len);
}
gpio_put(cs, 1);
}
void ST7789::update(bool dont_block) {
command(reg::RAMWR, width * height * sizeof(uint16_t), (const char*)frame_buffer);
/*if(dma_channel_is_busy(dma_channel) && dont_block) {
return;
}
dma_channel_wait_for_finish_blocking(dma_channel);
uint8_t r = reg::RAMWR;
gpio_put(cs, 0);
gpio_put(dc, 0); // command mode
spi_write_blocking(spi, &r, 1);
gpio_put(dc, 1); // data mode
dma_channel_set_read_addr(dma_channel, frame_buffer, true);*/
}
void ST7789::set_backlight(uint8_t brightness) {
// gamma correct the provided 0-255 brightness value onto a
// 0-65535 range for the pwm counter
float gamma = 2.8;
uint16_t value = (uint16_t)(pow((float)(brightness) / 255.0f, gamma) * 65535.0f + 0.5f);
pwm_set_gpio_level(bl, value);
}
void ST7789::vsync_callback(gpio_irq_callback_t callback) {
gpio_set_irq_enabled_with_callback(vsync, GPIO_IRQ_EDGE_RISE, true, callback);
}
void ST7789::flip(){
madctl ^= MADCTL::ROW_ORDER | MADCTL::COL_ORDER;
command(reg::MADCTL, 1, (char *)&madctl);
}
}
Reference in New Issue View Git Blame Copy Permalink