pimoroni-pico/drivers/st7567/st7567.cpp

184 lines
6.1 KiB
C++

#include "st7567.hpp"
#include <math.h>
#define BYTE_TO_BINARY_PATTERN "%c%c%c%c%c%c%c%c"
#define BYTE_TO_BINARY(byte) \
(byte & 0x80 ? '1' : '0'), \
(byte & 0x40 ? '1' : '0'), \
(byte & 0x20 ? '1' : '0'), \
(byte & 0x10 ? '1' : '0'), \
(byte & 0x08 ? '1' : '0'), \
(byte & 0x04 ? '1' : '0'), \
(byte & 0x02 ? '1' : '0'), \
(byte & 0x01 ? '1' : '0')
namespace pimoroni {
enum reg : uint8_t {
DISPOFF = 0xAE,//
DISPON = 0xAF,//
SETSTARTLINE = 0x40,//
STARTLINE_MASK = 0x3f,//
REG_RATIO = 0x20,//
SETPAGESTART = 0xb0,//
PAGESTART_MASK = 0x07,//
SETCOLL = 0x00, // # 0x00-0x0f: Set lower column address */
COLL_MASK = 0x0f,//
SETCOLH = 0x10, //# 0x10-0x1f: Set higher column address */
COLH_MASK = 0x0F,//
SEG_DIR_NORMAL = 0xa0, //# 0xa0: Column address 0 is mapped to SEG0 */
SEG_DIR_REV = 0xa1, //# 0xa1: Column address 128 is mapped to S
DISPNORMAL = 0xa6, //# 0xa6: Normal display */
DISPINVERSE = 0xa7, //# 0xa7: Inverse disp
DISPRAM = 0xa4, //# 0xa4: Resume to RAM content display */
DISPENTIRE = 0xa5, //# 0xa5: Entire display
BIAS_1_9 = 0xa2, //# 0xa2: Select BIAS setting 1/9 */
BIAS_1_7 = 0xa3, // # 0xa3: Select BIAS setting
ENTER_RMWMODE = 0xe0, //# 0xe0: Enter the Read Modify Write mode */
EXIT_RMWMODE = 0xee, //# 0xee: Leave the Read Modify Write mode */
EXIT_SOFTRST = 0xe2, // # 0xe2: Software RE
SETCOMNORMAL = 0xc0, //# 0xc0: Set COM output direction, normal mode */
SETCOMREVERSE = 0xc8, // # 0xc8: Set COM output direction, reverse m
POWERCTRL_VF = 0x29, //# 0x29: Control built-in power circuit */
POWERCTRL_VR = 0x2a, //# 0x2a: Control built-in power circuit */
POWERCTRL_VB = 0x2c, //# 0x2c: Control built-in power circuit */
POWERCTRL = 0x2f, // # 0x2c: Control built-in power circ
REG_RES_RR0 = 0x21, //# 0x21: Regulation Resistior ratio */
REG_RES_RR1 = 0x22, //# 0x22: Regulation Resistior ratio */
REG_RES_RR2 = 0x24, // # 0x24: Regulation Resistior ra
SETCONTRAST = 0x81, // # 0x81: Set contrast cont
SETBOOSTER = 0xf8, //# Set booster level */
SETBOOSTER4X = 0x00, //# Set booster level */
SETBOOSTER5X = 0x01 , // # Set booster le
NOP = 0xe3, //# 0xe3: NOP Command for no operation */
STARTBYTES = 0,
};
void ST7567::reset() {
if(reset_pin == PIN_UNUSED)
return;
gpio_put(reset_pin, 0); sleep_ms(10);
sleep_ms(100);
gpio_put(reset_pin, 1); sleep_ms(10);
sleep_ms(100);
}
void ST7567::init(bool auto_init_sequence) {
spi_init(spi, spi_baud);
gpio_set_function(reset_pin, GPIO_FUNC_SIO);
gpio_set_dir(reset_pin, GPIO_OUT);
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 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
}
//reset display
reset();
// if auto_init_sequence then send initialisation sequence
// for our standard displays based on the width and height
if(auto_init_sequence) {
command(reg::BIAS_1_7);
command(reg::SEG_DIR_NORMAL);
command(reg::SETCOMREVERSE);
command(reg::DISPNORMAL);
command(reg::SETSTARTLINE | 0x00); //Startline from 0x40-0x7F
command(reg::POWERCTRL);
command(reg::REG_RATIO | 4);
command(reg::DISPON);
command(reg::SETCONTRAST);
command(30); // defalut contrast level
}
if(bl != PIN_UNUSED) {
set_backlight(255); // Turn backlight on now surprises have passed
}
}
void ST7567::command(uint8_t command, size_t len, const char *data) {
gpio_put(cs, 0);
gpio_put(dc, 0); // command mode
spi_write_blocking(spi, &command, 1);
gpio_put(cs, 1);
sleep_us(100);
if(data) {
gpio_put(cs, 0);
gpio_put(dc, 1); // data mode
spi_write_blocking(spi, (const uint8_t*)data, len);
gpio_put(cs, 1);
}
}
// Native 16-bit framebuffer update
void ST7567::update(PicoGraphics *graphics) {
uint8_t *fb = (uint8_t *)graphics->frame_buffer;
uint8_t page_buffer[PAGESIZE];
uint8_t page_byte_selector;
uint8_t page_bit_selector;
for(uint8_t page=0; page < 8 ; page++) { //select page
for(uint16_t pixel_index=0 ; pixel_index < (PAGESIZE * 8) ; pixel_index++) { //cycle through a page worth of bits from the fb
page_byte_selector = ((pixel_index % 128));
page_bit_selector = (pixel_index / 128);
if(*fb & (0b10000000 >> (pixel_index % 8))) { // check selected pixel is present
page_buffer[page_byte_selector] |= (1 << page_bit_selector);
}
else {
page_buffer[page_byte_selector] &= ~( 1 << page_bit_selector);
}
if((pixel_index % 8) >= 7) { //increment fb pointer at end of byte
fb++;
}
}
if(graphics->pen_type == PicoGraphics::PEN_1BIT) {
command(reg::ENTER_RMWMODE);
command(reg::SETPAGESTART | page);
command(reg::SETCOLL);
command(reg::SETCOLH);
gpio_put(dc, 1); // data mode
gpio_put(cs, 0);
spi_write_blocking(spi, &page_buffer[0], PAGESIZE );
gpio_put(cs, 1);
gpio_put(dc, 0); // Back to command mode
}
else { //other pen types incompatable
return;
}
}
gpio_put(cs, 1);
}
void ST7567::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);
}
}