/* 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 . */ #include "Display_SSD1306_I2C.h" #include #include #include static const AP_HAL::HAL& hal = AP_HAL::get_HAL(); // constructor Display_SSD1306_I2C::Display_SSD1306_I2C(AP_HAL::OwnPtr dev) : _dev(std::move(dev)) { _displaybuffer_sem = hal.util->new_semaphore(); } bool Display_SSD1306_I2C::hw_init() { struct PACKED { uint8_t reg; uint8_t seq[31]; } init_seq = { 0x0, { // LEGEND: // *** is out of sequence for init steps recommended in datasheet // +++ not listed in sequence for init steps recommended in datasheet 0xAE, // Display OFF 0xD5, 0x80, // *** Set Display Clock Divide Ratio and Oscillator Frequency // Clock Divide Ratio: 0b (== 1) // Oscillator Frequency: 1000b (== +0%) 0xA8, 0x3F, // MUX Ratio: 111111b (== 64MUX) 0xD3, 0x00, // Display Offset: 0b (== 0) 0x40, // Display Start Line: 0b (== 0) 0x8D, 0x14, // *** Enable charge pump regulator: 1b (== Enable) 0x20, 0x00, // *** Memory Addressing Mode: 00b (== Horizontal Addressing Mode) 0xA1, // Segment re-map: 1b (== column address 127 is mapped to SEG0) 0xC8, // COM Output Scan Direction: 1b (== remapped mode. Scan from COM[N-1] to COM0) 0xDA, 0x12, // COM Pins hardware configuration: 01b (POR) // (== Alternative COM pin configuration + Disable COM Left/Right remap) 0x81, 0xCF, // Contrast Control: 0xCF (== 207 decimal, range 0..255) 0xD9, 0xF1, // +++ Pre-charge Period: 0xF1 (== 1 DCLK P1 + 15 DCLK P2) 0xDB, 0x40, // +++ VCOMH Deselect Level: 100b (INVALID?!) (== ?!) 0xA4, // Entire Display ON (ignoring RAM): (== OFF) 0xA6, // Normal/Inverse Display: 0b (== Normal) 0xAF, // Display ON: 1b (== ON) 0x21, 0, 127, // +++ Column Address: (== start:0, end:127) 0x22, 0, 7 // +++ Page Address: (== start:0, end:7) } }; memset(_displaybuffer, 0, SSD1306_COLUMNS * SSD1306_ROWS_PER_PAGE); // take i2c bus semaphore if (!_dev || !_dev->get_semaphore()->take(HAL_SEMAPHORE_BLOCK_FOREVER)) { return false; } // init display bool success = _dev->transfer((uint8_t *)&init_seq, sizeof(init_seq), nullptr, 0); // give back i2c semaphore _dev->get_semaphore()->give(); if (success) { _need_hw_update = true; _dev->register_periodic_callback(20000, FUNCTOR_BIND_MEMBER(&Display_SSD1306_I2C::_timer, void)); } return success; } void Display_SSD1306_I2C::hw_update() { _need_hw_update = true; } void Display_SSD1306_I2C::_timer() { if (!_need_hw_update) { return; } _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_COLUMNS/2]; } display_buffer = { 0x40, {} }; // write buffer to display for (uint8_t i = 0; i < (SSD1306_ROWS / SSD1306_ROWS_PER_PAGE); i++) { command.cmd[4] = i; _dev->transfer((uint8_t *)&command, sizeof(command), nullptr, 0); if (_displaybuffer_sem->take(0)) { memcpy(&display_buffer.db[0], &_displaybuffer[i * SSD1306_COLUMNS], SSD1306_COLUMNS/2); _displaybuffer_sem->give(); _dev->transfer((uint8_t *)&display_buffer, SSD1306_COLUMNS/2 + 1, nullptr, 0); } if (_displaybuffer_sem->take(0)) { memcpy(&display_buffer.db[0], &_displaybuffer[i * SSD1306_COLUMNS + SSD1306_COLUMNS/2 ], SSD1306_COLUMNS/2); _displaybuffer_sem->give(); _dev->transfer((uint8_t *)&display_buffer, SSD1306_COLUMNS/2 + 1, nullptr, 0); } } } void Display_SSD1306_I2C::set_pixel(uint16_t x, uint16_t y) { // check x, y range if ((x >= SSD1306_COLUMNS) || (y >= SSD1306_ROWS)) { return; } if (!_displaybuffer_sem->take(0)) { return; } // set pixel in buffer _displaybuffer[x + (y / 8 * SSD1306_COLUMNS)] |= 1 << (y % 8); _displaybuffer_sem->give(); } void Display_SSD1306_I2C::clear_pixel(uint16_t x, uint16_t y) { // check x, y range if ((x >= SSD1306_COLUMNS) || (y >= SSD1306_ROWS)) { return; } if (!_displaybuffer_sem->take(0)) { return; } // clear pixel in buffer _displaybuffer[x + (y / 8 * SSD1306_COLUMNS)] &= ~(1 << (y % 8)); _displaybuffer_sem->give(); } void Display_SSD1306_I2C::clear_screen() { if (!_displaybuffer_sem->take(0)) { return; } memset(_displaybuffer, 0, SSD1306_COLUMNS * SSD1306_ROWS_PER_PAGE); _displaybuffer_sem->give(); }