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Add ST7565 LCD driver (#13089)

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Co-authored-by: Joakim Tufvegren <jocke@barbanet.com>
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Ryan 2021-06-10 17:16:09 +10:00 • committed by GitHub
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drivers/lcd/st7565.c Normal file
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/*
Copyright 2021
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include "st7565.h"
#include <string.h>
#include "keyboard.h"
#include "progmem.h"
#include "timer.h"
#include "wait.h"
#include ST7565_FONT_H
// Fundamental Commands
#define CONTRAST 0x81
#define DISPLAY_ALL_ON 0xA5
#define DISPLAY_ALL_ON_RESUME 0xA4
#define NORMAL_DISPLAY 0xA6
#define DISPLAY_ON 0xAF
#define DISPLAY_OFF 0xAE
#define NOP 0xE3
// Addressing Setting Commands
#define PAM_SETCOLUMN_LSB 0x00
#define PAM_SETCOLUMN_MSB 0x10
#define PAM_PAGE_ADDR 0xB0 // 0xb0 -- 0xb7
// Hardware Configuration Commands
#define DISPLAY_START_LINE 0x40
#define SEGMENT_REMAP 0xA0
#define SEGMENT_REMAP_INV 0xA1
#define COM_SCAN_INC 0xC0
#define COM_SCAN_DEC 0xC8
#define LCD_BIAS_7 0xA3
#define LCD_BIAS_9 0xA2
#define RESISTOR_RATIO 0x20
#define POWER_CONTROL 0x28
// Misc defines
#ifndef ST7565_BLOCK_COUNT
# define ST7565_BLOCK_COUNT (sizeof(ST7565_BLOCK_TYPE) * 8)
#endif
#ifndef ST7565_BLOCK_SIZE
# define ST7565_BLOCK_SIZE (ST7565_MATRIX_SIZE / ST7565_BLOCK_COUNT)
#endif
#define ST7565_ALL_BLOCKS_MASK (((((ST7565_BLOCK_TYPE)1 << (ST7565_BLOCK_COUNT - 1)) - 1) << 1) | 1)
#define HAS_FLAGS(bits, flags) ((bits & flags) == flags)
// Display buffer's is the same as the display memory layout
// this is so we don't end up with rounding errors with
// parts of the display unusable or don't get cleared correctly
// and also allows for drawing & inverting
uint8_t st7565_buffer[ST7565_MATRIX_SIZE];
uint8_t * st7565_cursor;
ST7565_BLOCK_TYPE st7565_dirty = 0;
bool st7565_initialized = false;
bool st7565_active = false;
display_rotation_t st7565_rotation = DISPLAY_ROTATION_0;
#if ST7565_TIMEOUT > 0
uint32_t st7565_timeout;
#endif
#if ST7565_UPDATE_INTERVAL > 0
uint16_t st7565_update_timeout;
#endif
// Flips the rendering bits for a character at the current cursor position
static void InvertCharacter(uint8_t *cursor) {
const uint8_t *end = cursor + ST7565_FONT_WIDTH;
while (cursor < end) {
*cursor = ~(*cursor);
cursor++;
}
}
bool st7565_init(display_rotation_t rotation) {
setPinOutput(ST7565_A0_PIN);
writePinHigh(ST7565_A0_PIN);
setPinOutput(ST7565_RST_PIN);
writePinHigh(ST7565_RST_PIN);
st7565_rotation = st7565_init_user(rotation);
spi_init();
spi_start(ST7565_SS_PIN, false, 0, ST7565_SPI_CLK_DIVISOR);
st7565_reset();
st7565_send_cmd(LCD_BIAS_7);
if (!HAS_FLAGS(st7565_rotation, DISPLAY_ROTATION_180)) {
st7565_send_cmd(SEGMENT_REMAP);
st7565_send_cmd(COM_SCAN_DEC);
} else {
st7565_send_cmd(SEGMENT_REMAP_INV);
st7565_send_cmd(COM_SCAN_INC);
}
st7565_send_cmd(DISPLAY_START_LINE | 0x00);
st7565_send_cmd(CONTRAST);
st7565_send_cmd(ST7565_CONTRAST);
st7565_send_cmd(RESISTOR_RATIO | 0x01);
st7565_send_cmd(POWER_CONTROL | 0x04);
wait_ms(50);
st7565_send_cmd(POWER_CONTROL | 0x06);
wait_ms(50);
st7565_send_cmd(POWER_CONTROL | 0x07);
wait_ms(10);
st7565_send_cmd(DISPLAY_ON);
st7565_send_cmd(DISPLAY_ALL_ON_RESUME);
st7565_send_cmd(NORMAL_DISPLAY);
spi_stop();
#if ST7565_TIMEOUT > 0
st7565_timeout = timer_read32() + ST7565_TIMEOUT;
#endif
st7565_clear();
st7565_initialized = true;
st7565_active = true;
return true;
}
__attribute__((weak)) display_rotation_t st7565_init_user(display_rotation_t rotation) { return rotation; }
void st7565_clear(void) {
memset(st7565_buffer, 0, sizeof(st7565_buffer));
st7565_cursor = &st7565_buffer[0];
st7565_dirty = ST7565_ALL_BLOCKS_MASK;
}
uint8_t crot(uint8_t a, int8_t n) {
const uint8_t mask = 0x7;
n &= mask;
return a << n | a >> (-n & mask);
}
void st7565_render(void) {
if (!st7565_initialized) {
return;
}
// Do we have work to do?
st7565_dirty &= ST7565_ALL_BLOCKS_MASK;
if (!st7565_dirty) {
return;
}
// Find first dirty block
uint8_t update_start = 0;
while (!(st7565_dirty & ((ST7565_BLOCK_TYPE)1 << update_start))) {
++update_start;
}
// Calculate commands to set memory addressing bounds.
uint8_t start_page = ST7565_BLOCK_SIZE * update_start / ST7565_DISPLAY_WIDTH;
uint8_t start_column = ST7565_BLOCK_SIZE * update_start % ST7565_DISPLAY_WIDTH;
// IC has 132 segment drivers, for panels with less width we need to offset the starting column
if (HAS_FLAGS(st7565_rotation, DISPLAY_ROTATION_180)) {
start_column += (132 - ST7565_DISPLAY_WIDTH);
}
spi_start(ST7565_SS_PIN, false, 0, ST7565_SPI_CLK_DIVISOR);
st7565_send_cmd(PAM_PAGE_ADDR | start_page);
st7565_send_cmd(PAM_SETCOLUMN_LSB | ((ST7565_COLUMN_OFFSET + start_column) & 0x0f));
st7565_send_cmd(PAM_SETCOLUMN_MSB | ((ST7565_COLUMN_OFFSET + start_column) >> 4 & 0x0f));
st7565_send_data(&st7565_buffer[ST7565_BLOCK_SIZE * update_start], ST7565_BLOCK_SIZE);
// Turn on display if it is off
st7565_on();
// Clear dirty flag
st7565_dirty &= ~((ST7565_BLOCK_TYPE)1 << update_start);
}
void st7565_set_cursor(uint8_t col, uint8_t line) {
uint16_t index = line * ST7565_DISPLAY_WIDTH + col * ST7565_FONT_WIDTH;
// Out of bounds?
if (index >= ST7565_MATRIX_SIZE) {
index = 0;
}
st7565_cursor = &st7565_buffer[index];
}
void st7565_advance_page(bool clearPageRemainder) {
uint16_t index = st7565_cursor - &st7565_buffer[0];
uint8_t remaining = ST7565_DISPLAY_WIDTH - (index % ST7565_DISPLAY_WIDTH);
if (clearPageRemainder) {
// Remaining Char count
remaining = remaining / ST7565_FONT_WIDTH;
// Write empty character until next line
while (remaining--) st7565_write_char(' ', false);
} else {
// Next page index out of bounds?
if (index + remaining >= ST7565_MATRIX_SIZE) {
index = 0;
remaining = 0;
}
st7565_cursor = &st7565_buffer[index + remaining];
}
}
void st7565_advance_char(void) {
uint16_t nextIndex = st7565_cursor - &st7565_buffer[0] + ST7565_FONT_WIDTH;
uint8_t remainingSpace = ST7565_DISPLAY_WIDTH - (nextIndex % ST7565_DISPLAY_WIDTH);
// Do we have enough space on the current line for the next character
if (remainingSpace < ST7565_FONT_WIDTH) {
nextIndex += remainingSpace;
}
// Did we go out of bounds
if (nextIndex >= ST7565_MATRIX_SIZE) {
nextIndex = 0;
}
// Update cursor position
st7565_cursor = &st7565_buffer[nextIndex];
}
// Main handler that writes character data to the display buffer
void st7565_write_char(const char data, bool invert) {
// Advance to the next line if newline
if (data == '\n') {
// Old source wrote ' ' until end of line...
st7565_advance_page(true);
return;
}
if (data == '\r') {
st7565_advance_page(false);
return;
}
// copy the current render buffer to check for dirty after
static uint8_t st7565_temp_buffer[ST7565_FONT_WIDTH];
memcpy(&st7565_temp_buffer, st7565_cursor, ST7565_FONT_WIDTH);
_Static_assert(sizeof(font) >= ((ST7565_FONT_END + 1 - ST7565_FONT_START) * ST7565_FONT_WIDTH), "ST7565_FONT_END references outside array");
// set the reder buffer data
uint8_t cast_data = (uint8_t)data; // font based on unsigned type for index
if (cast_data < ST7565_FONT_START || cast_data > ST7565_FONT_END) {
memset(st7565_cursor, 0x00, ST7565_FONT_WIDTH);
} else {
const uint8_t *glyph = &font[(cast_data - ST7565_FONT_START) * ST7565_FONT_WIDTH];
memcpy_P(st7565_cursor, glyph, ST7565_FONT_WIDTH);
}
// Invert if needed
if (invert) {
InvertCharacter(st7565_cursor);
}
// Dirty check
if (memcmp(&st7565_temp_buffer, st7565_cursor, ST7565_FONT_WIDTH)) {
uint16_t index = st7565_cursor - &st7565_buffer[0];
st7565_dirty |= ((ST7565_BLOCK_TYPE)1 << (index / ST7565_BLOCK_SIZE));
// Edgecase check if the written data spans the 2 chunks
st7565_dirty |= ((ST7565_BLOCK_TYPE)1 << ((index + ST7565_FONT_WIDTH - 1) / ST7565_BLOCK_SIZE));
}
// Finally move to the next char
st7565_advance_char();
}
void st7565_write(const char *data, bool invert) {
const char *end = data + strlen(data);
while (data < end) {
st7565_write_char(*data, invert);
data++;
}
}
void st7565_write_ln(const char *data, bool invert) {
st7565_write(data, invert);
st7565_advance_page(true);
}
void st7565_pan(bool left) {
uint16_t i = 0;
for (uint16_t y = 0; y < ST7565_DISPLAY_HEIGHT / 8; y++) {
if (left) {
for (uint16_t x = 0; x < ST7565_DISPLAY_WIDTH - 1; x++) {
i = y * ST7565_DISPLAY_WIDTH + x;
st7565_buffer[i] = st7565_buffer[i + 1];
}
} else {
for (uint16_t x = ST7565_DISPLAY_WIDTH - 1; x > 0; x--) {
i = y * ST7565_DISPLAY_WIDTH + x;
st7565_buffer[i] = st7565_buffer[i - 1];
}
}
}
st7565_dirty = ST7565_ALL_BLOCKS_MASK;
}
display_buffer_reader_t st7565_read_raw(uint16_t start_index) {
if (start_index > ST7565_MATRIX_SIZE) start_index = ST7565_MATRIX_SIZE;
display_buffer_reader_t ret_reader;
ret_reader.current_element = &st7565_buffer[start_index];
ret_reader.remaining_element_count = ST7565_MATRIX_SIZE - start_index;
return ret_reader;
}
void st7565_write_raw_byte(const char data, uint16_t index) {
if (index > ST7565_MATRIX_SIZE) index = ST7565_MATRIX_SIZE;
if (st7565_buffer[index] == data) return;
st7565_buffer[index] = data;
st7565_dirty |= ((ST7565_BLOCK_TYPE)1 << (index / ST7565_BLOCK_SIZE));
}
void st7565_write_raw(const char *data, uint16_t size) {
uint16_t cursor_start_index = st7565_cursor - &st7565_buffer[0];
if ((size + cursor_start_index) > ST7565_MATRIX_SIZE) size = ST7565_MATRIX_SIZE - cursor_start_index;
for (uint16_t i = cursor_start_index; i < cursor_start_index + size; i++) {
if (st7565_buffer[i] == data[i]) continue;
st7565_buffer[i] = data[i];
st7565_dirty |= ((ST7565_BLOCK_TYPE)1 << (i / ST7565_BLOCK_SIZE));
}
}
void st7565_write_pixel(uint8_t x, uint8_t y, bool on) {
if (x >= ST7565_DISPLAY_WIDTH) {
return;
}
uint16_t index = x + (y / 8) * ST7565_DISPLAY_WIDTH;
if (index >= ST7565_MATRIX_SIZE) {
return;
}
uint8_t data = st7565_buffer[index];
if (on) {
data |= (1 << (y % 8));
} else {
data &= ~(1 << (y % 8));
}
if (st7565_buffer[index] != data) {
st7565_buffer[index] = data;
st7565_dirty |= ((ST7565_BLOCK_TYPE)1 << (index / ST7565_BLOCK_SIZE));
}
}
#if defined(__AVR__)
void st7565_write_P(const char *data, bool invert) {
uint8_t c = pgm_read_byte(data);
while (c != 0) {
st7565_write_char(c, invert);
c = pgm_read_byte(++data);
}
}
void st7565_write_ln_P(const char *data, bool invert) {
st7565_write_P(data, invert);
st7565_advance_page(true);
}
void st7565_write_raw_P(const char *data, uint16_t size) {
uint16_t cursor_start_index = st7565_cursor - &st7565_buffer[0];
if ((size + cursor_start_index) > ST7565_MATRIX_SIZE) size = ST7565_MATRIX_SIZE - cursor_start_index;
for (uint16_t i = cursor_start_index; i < cursor_start_index + size; i++) {
uint8_t c = pgm_read_byte(data++);
if (st7565_buffer[i] == c) continue;
st7565_buffer[i] = c;
st7565_dirty |= ((ST7565_BLOCK_TYPE)1 << (i / ST7565_BLOCK_SIZE));
}
}
#endif // defined(__AVR__)
bool st7565_on(void) {
if (!st7565_initialized) {
return st7565_active;
}
#if ST7565_TIMEOUT > 0
st7565_timeout = timer_read32() + ST7565_TIMEOUT;
#endif
if (!st7565_active) {
spi_start(ST7565_SS_PIN, false, 0, ST7565_SPI_CLK_DIVISOR);
st7565_send_cmd(DISPLAY_ON);
spi_stop();
st7565_active = true;
st7565_on_user();
}
return st7565_active;
}
__attribute__((weak)) void st7565_on_user(void) {}
bool st7565_off(void) {
if (!st7565_initialized) {
return !st7565_active;
}
if (st7565_active) {
spi_start(ST7565_SS_PIN, false, 0, ST7565_SPI_CLK_DIVISOR);
st7565_send_cmd(DISPLAY_OFF);
spi_stop();
st7565_active = false;
st7565_off_user();
}
return !st7565_active;
}
__attribute__((weak)) void st7565_off_user(void) {}
bool st7565_is_on(void) { return st7565_active; }
uint8_t st7565_max_chars(void) { return ST7565_DISPLAY_WIDTH / ST7565_FONT_WIDTH; }
uint8_t st7565_max_lines(void) { return ST7565_DISPLAY_HEIGHT / ST7565_FONT_HEIGHT; }
void st7565_task(void) {
if (!st7565_initialized) {
return;
}
#if ST7565_UPDATE_INTERVAL > 0
if (timer_elapsed(st7565_update_timeout) >= ST7565_UPDATE_INTERVAL) {
st7565_update_timeout = timer_read();
st7565_set_cursor(0, 0);
st7565_task_user();
}
#else
st7565_set_cursor(0, 0);
st7565_task_user();
#endif
// Smart render system, no need to check for dirty
st7565_render();
// Display timeout check
#if ST7565_TIMEOUT > 0
if (st7565_active && timer_expired32(timer_read32(), st7565_timeout)) {
st7565_off();
}
#endif
}
__attribute__((weak)) void st7565_task_user(void) {}
void st7565_reset(void) {
writePinLow(ST7565_RST_PIN);
wait_ms(20);
writePinHigh(ST7565_RST_PIN);
wait_ms(20);
}
spi_status_t st7565_send_cmd(uint8_t cmd) {
writePinLow(ST7565_A0_PIN);
return spi_write(cmd);
}
spi_status_t st7565_send_data(uint8_t *data, uint16_t length) {
writePinHigh(ST7565_A0_PIN);
return spi_transmit(data, length);
}

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/*
Copyright 2021
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#pragma once
#include <stdint.h>
#include <stdbool.h>
#include "spi_master.h"
#ifndef ST7565_DISPLAY_WIDTH
# define ST7565_DISPLAY_WIDTH 128
#endif
#ifndef ST7565_DISPLAY_HEIGHT
# define ST7565_DISPLAY_HEIGHT 32
#endif
#ifndef ST7565_MATRIX_SIZE
# define ST7565_MATRIX_SIZE (ST7565_DISPLAY_HEIGHT / 8 * ST7565_DISPLAY_WIDTH) // 1024 (compile time mathed)
#endif
#ifndef ST7565_BLOCK_TYPE
# define ST7565_BLOCK_TYPE uint16_t
#endif
#ifndef ST7565_BLOCK_COUNT
# define ST7565_BLOCK_COUNT (sizeof(ST7565_BLOCK_TYPE) * 8) // 32 (compile time mathed)
#endif
#ifndef ST7565_BLOCK_SIZE
# define ST7565_BLOCK_SIZE (ST7565_MATRIX_SIZE / ST7565_BLOCK_COUNT) // 32 (compile time mathed)
#endif
// the column address corresponding to the first column in the display hardware
#if !defined(ST7565_COLUMN_OFFSET)
# define ST7565_COLUMN_OFFSET 0
#endif
// spi clock divisor
#if !defined(ST7565_SPI_CLK_DIVISOR)
# define ST7565_SPI_CLK_DIVISOR 4
#endif
// Custom font file to use
#if !defined(ST7565_FONT_H)
# define ST7565_FONT_H "glcdfont.c"
#endif
// unsigned char value of the first character in the font file
#if !defined(ST7565_FONT_START)
# define ST7565_FONT_START 0
#endif
// unsigned char value of the last character in the font file
#if !defined(ST7565_FONT_END)
# define ST7565_FONT_END 223
#endif
// Font render width
#if !defined(ST7565_FONT_WIDTH)
# define ST7565_FONT_WIDTH 6
#endif
// Font render height
#if !defined(ST7565_FONT_HEIGHT)
# define ST7565_FONT_HEIGHT 8
#endif
// Default contrast level
#if !defined(ST7565_CONTRAST)
# define ST7565_CONTRAST 32
#endif
#if !defined(ST7565_TIMEOUT)
# if defined(ST7565_DISABLE_TIMEOUT)
# define ST7565_TIMEOUT 0
# else
# define ST7565_TIMEOUT 60000
# endif
#endif
#if !defined(ST7565_UPDATE_INTERVAL) && defined(SPLIT_KEYBOARD)
# define ST7565_UPDATE_INTERVAL 50
#endif
typedef struct __attribute__((__packed__)) {
uint8_t *current_element;
uint16_t remaining_element_count;
} display_buffer_reader_t;
// Rotation enum values are flags
typedef enum { DISPLAY_ROTATION_0, DISPLAY_ROTATION_180 } display_rotation_t;
// Initialize the display, rotating the rendered output based on the define passed in.
// Returns true if the display was initialized successfully
bool st7565_init(display_rotation_t rotation);
// Called at the start of st7565_init, weak function overridable by the user
// rotation - the value passed into st7565_init
// Return new display_rotation_t if you want to override default rotation
display_rotation_t st7565_init_user(display_rotation_t rotation);
// Clears the display buffer, resets cursor position to 0, and sets the buffer to dirty for rendering
void st7565_clear(void);
// Renders the dirty chunks of the buffer to display
void st7565_render(void);
// Moves cursor to character position indicated by column and line, wraps if out of bounds
// Max column denoted by 'st7565_max_chars()' and max lines by 'st7565_max_lines()' functions
void st7565_set_cursor(uint8_t col, uint8_t line);
// Advances the cursor to the next page, writing ' ' if true
// Wraps to the begining when out of bounds
void st7565_advance_page(bool clearPageRemainder);
// Moves the cursor forward 1 character length
// Advance page if there is not enough room for the next character
// Wraps to the begining when out of bounds
void st7565_advance_char(void);
// Writes a single character to the buffer at current cursor position
// Advances the cursor while writing, inverts the pixels if true
// Main handler that writes character data to the display buffer
void st7565_write_char(const char data, bool invert);
// Writes a string to the buffer at current cursor position
// Advances the cursor while writing, inverts the pixels if true
void st7565_write(const char *data, bool invert);
// Writes a string to the buffer at current cursor position
// Advances the cursor while writing, inverts the pixels if true
// Advances the cursor to the next page, wiring ' ' to the remainder of the current page
void st7565_write_ln(const char *data, bool invert);
// Pans the buffer to the right (or left by passing true) by moving contents of the buffer
// Useful for moving the screen in preparation for new drawing
void st7565_pan(bool left);
// Returns a pointer to the requested start index in the buffer plus remaining
// buffer length as struct
display_buffer_reader_t st7565_read_raw(uint16_t start_index);
// Writes a string to the buffer at current cursor position
void st7565_write_raw(const char *data, uint16_t size);
// Writes a single byte into the buffer at the specified index
void st7565_write_raw_byte(const char data, uint16_t index);
// Sets a specific pixel on or off
// Coordinates start at top-left and go right and down for positive x and y
void st7565_write_pixel(uint8_t x, uint8_t y, bool on);
#if defined(__AVR__)
// Writes a PROGMEM string to the buffer at current cursor position
// Advances the cursor while writing, inverts the pixels if true
// Remapped to call 'void st7565_write(const char *data, bool invert);' on ARM
void st7565_write_P(const char *data, bool invert);
// Writes a PROGMEM string to the buffer at current cursor position
// Advances the cursor while writing, inverts the pixels if true
// Advances the cursor to the next page, wiring ' ' to the remainder of the current page
// Remapped to call 'void st7565_write_ln(const char *data, bool invert);' on ARM
void st7565_write_ln_P(const char *data, bool invert);
// Writes a PROGMEM string to the buffer at current cursor position
void st7565_write_raw_P(const char *data, uint16_t size);
#else
# define st7565_write_P(data, invert) st7565_write(data, invert)
# define st7565_write_ln_P(data, invert) st7565_write_ln(data, invert)
# define st7565_write_raw_P(data, size) st7565_write_raw(data, size)
#endif // defined(__AVR__)
// Can be used to manually turn on the screen if it is off
// Returns true if the screen was on or turns on
bool st7565_on(void);
// Called when st7565_on() turns on the screen, weak function overridable by the user
// Not called if the screen is already on
void st7565_on_user(void);
// Can be used to manually turn off the screen if it is on
// Returns true if the screen was off or turns off
bool st7565_off(void);
// Called when st7565_off() turns off the screen, weak function overridable by the user
// Not called if the screen is already off
void st7565_off_user(void);
// Returns true if the screen is currently on, false if it is
// not
bool st7565_is_on(void);
// Basically it's st7565_render, but with timeout management and st7565_task_user calling!
void st7565_task(void);
// Called at the start of st7565_task, weak function overridable by the user
void st7565_task_user(void);
// Returns the maximum number of characters that will fit on a line
uint8_t st7565_max_chars(void);
// Returns the maximum number of lines that will fit on the display
uint8_t st7565_max_lines(void);
void st7565_reset(void);
spi_status_t st7565_send_cmd(uint8_t cmd);
spi_status_t st7565_send_data(uint8_t *data, uint16_t length);