ardupilot/libraries/AP_Notify/Display_SSD1306_I2C.cpp

118 lines
3.2 KiB
C++

/*
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 3 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 "Display_SSD1306_I2C.h"
#include <utility>
#include <AP_HAL/AP_HAL.h>
#include <AP_HAL/I2CDevice.h>
#define SSD1306_I2C_BUS 2
#define SSD1306_I2C_ADDR 0x3C // default I2C bus address
static const AP_HAL::HAL& hal = AP_HAL::get_HAL();
bool Display_SSD1306_I2C::hw_init()
{
struct {
uint8_t reg;
uint8_t seq[31];
} init_seq = { 0x0, {0xAE, 0xD5, 0x80, 0xA8, 0x3F, 0xD3,
0x00, 0x40, 0x8D, 0x14, 0x20, 0x00,
0xA1, 0xC8, 0xDA, 0x12, 0x81, 0xCF,
0xD9, 0xF1, 0xDB, 0x40, 0xA4, 0xA6,
0xAF, 0x21, 0, 127, 0x22, 0, 7 } };
_dev = std::move(hal.i2c_mgr->get_device(SSD1306_I2C_BUS, SSD1306_I2C_ADDR));
// take i2c bus sempahore
if (!_dev || !_dev->get_semaphore()->take(HAL_SEMAPHORE_BLOCK_FOREVER)) {
return false;
}
// init display
_dev->transfer((uint8_t *)&init_seq, sizeof(init_seq), nullptr, 0);
// give back i2c semaphore
_dev->get_semaphore()->give();
_need_hw_update = true;
_dev->register_periodic_callback(20000, FUNCTOR_BIND_MEMBER(&Display_SSD1306_I2C::_timer, bool));
return true;
}
bool Display_SSD1306_I2C::hw_update()
{
_need_hw_update = true;
return true;
}
bool Display_SSD1306_I2C::_timer()
{
if (!_need_hw_update) {
return true;
}
_need_hw_update = false;
struct PACKED {
uint8_t reg;
uint8_t cmd[6];
} command = { 0x0, {0x21, 0, 127, 0x22, 0, 7} };
struct PACKED {
uint8_t reg;
uint8_t db[SSD1306_ROWS];
} display_buffer = { 0x40, {} };
// write buffer to display
for (uint8_t i = 0; i < (SSD1306_COLUMNS / SSD1306_COLUMNS_PER_PAGE); i++) {
command.cmd[4] = i;
_dev->transfer((uint8_t *)&command, sizeof(command), nullptr, 0);
memcpy(&display_buffer.db[0], &_displaybuffer[i * SSD1306_ROWS], SSD1306_ROWS);
_dev->transfer((uint8_t *)&display_buffer, sizeof(display_buffer), nullptr, 0);
}
return true;
}
bool Display_SSD1306_I2C::set_pixel(uint16_t x, uint16_t y)
{
// check x, y range
if ((x >= SSD1306_ROWS) || (y >= SSD1306_COLUMNS)) {
return false;
}
// set pixel in buffer
_displaybuffer[x + (y / 8 * SSD1306_ROWS)] |= 1 << (y % 8);
return true;
}
bool Display_SSD1306_I2C::clear_pixel(uint16_t x, uint16_t y)
{
// check x, y range
if ((x >= SSD1306_ROWS) || (y >= SSD1306_COLUMNS)) {
return false;
}
// clear pixel in buffer
_displaybuffer[x + (y / 8 * SSD1306_ROWS)] &= ~(1 << (y % 8));
return true;
}