Library for interacting with seeedstudio epaper
Dependents: display-puck display-puck
EPD.cpp
- Committer:
- sigveseb
- Date:
- 2014-07-17
- Revision:
- 0:6ac5ba1343bf
- Child:
- 1:2f62e2b80305
File content as of revision 0:6ac5ba1343bf:
// Copyright 2013 Pervasive Displays, Inc. // // Licensed under the Apache License, Version 2.0 (the "License"); // you may not use this file except in compliance with the License. // You may obtain a copy of the License at: // // http://www.apache.org/licenses/LICENSE-2.0 // // Unless required by applicable law or agreed to in writing, // software distributed under the License is distributed on an // "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either // express or implied. See the License for the specific language // governing permissions and limitations under the License. #include <limits.h> #include <SPI.h> #include "EPD.h" #include <mbed.h> // delays - more consistent naming #define Delay_ms(ms) delay(ms) #define Delay_us(us) delayMicroseconds(us) // inline arrays #define ARRAY(type, ...) ((type[]){__VA_ARGS__}) #define CU8(...) (ARRAY(const uint8_t, __VA_ARGS__)) Timer timer; SPI spi(p20, p22, p25); Serial pq(USBTX, USBRX); static void SPI_put(uint8_t c); static void SPI_put_wait(uint8_t c, DigitalIn busy_pin); static void SPI_send(DigitalOut cs_pin, const uint8_t *buffer, uint16_t length); static void SPI_on(); EPD_Class::EPD_Class(PinName Pin_EPD_CS, PinName Pin_PANEL_ON, PinName Pin_BORDER, PinName Pin_DISCHARGE, PinName Pin_PWM, PinName Pin_RESET, PinName Pin_BUSY) : EPD_Pin_EPD_CS(Pin_EPD_CS), EPD_Pin_PANEL_ON(Pin_PANEL_ON), EPD_Pin_BORDER(Pin_BORDER), EPD_Pin_DISCHARGE(Pin_DISCHARGE), EPD_Pin_PWM(Pin_PWM), EPD_Pin_RESET(Pin_RESET), EPD_Pin_BUSY(Pin_BUSY) { } void EPD_Class::begin(EPD_size sz) { this->size = sz; this->stage_time = 480; // milliseconds this->lines_per_display = 96; this->dots_per_line = 128; this->bytes_per_line = 128 / 8; this->bytes_per_scan = 96 / 4; this->filler = false; timer.start(); this->EPD_Pin_PWM.period(1.0/300000.0); // display size dependant items { static uint8_t cs[] = {0x72, 0x00, 0x00, 0x00, 0x00, 0x00, 0x0f, 0xff, 0x00}; static uint8_t gs[] = {0x72, 0x03}; this->channel_select = cs; this->channel_select_length = sizeof(cs); this->gate_source = gs; this->gate_source_length = sizeof(gs); } // set up size structure switch (size) { default: case EPD_1_44: // default so no change break; case EPD_2_0: { this->lines_per_display = 96; this->dots_per_line = 200; this->bytes_per_line = 200 / 8; this->bytes_per_scan = 96 / 4; this->filler = true; static uint8_t cs[] = {0x72, 0x00, 0x00, 0x00, 0x00, 0x01, 0xff, 0xe0, 0x00}; static uint8_t gs[] = {0x72, 0x03}; this->channel_select = cs; this->channel_select_length = sizeof(cs); this->gate_source = gs; this->gate_source_length = sizeof(gs); break; } case EPD_2_7: { this->stage_time = 630; // milliseconds this->lines_per_display = 176; this->dots_per_line = 264; this->bytes_per_line = 264 / 8; this->bytes_per_scan = 176 / 4; this->filler = true; static uint8_t cs[] = {0x72, 0x00, 0x00, 0x00, 0x7f, 0xff, 0xfe, 0x00, 0x00}; static uint8_t gs[] = {0x72, 0x00}; this->channel_select = cs; this->channel_select_length = sizeof(cs); this->gate_source = gs; this->gate_source_length = sizeof(gs); break; } } this->factored_stage_time = this->stage_time; } void EPD_Class::start() { this->EPD_Pin_PWM = 0.5; this->EPD_Pin_RESET = 0; this->EPD_Pin_PANEL_ON = 0; this->EPD_Pin_DISCHARGE = 0; this->EPD_Pin_BORDER = 0; this->EPD_Pin_EPD_CS = 0; spi.format(8,0); spi.frequency(10000000); SPI_on(); wait_ms(5); this->EPD_Pin_PANEL_ON = 1; wait_ms(10); this->EPD_Pin_RESET = 1; this->EPD_Pin_BORDER = 1; this->EPD_Pin_EPD_CS = 1; wait_ms(5); this->EPD_Pin_RESET = 0; wait_ms(5); this->EPD_Pin_RESET = 1; wait_ms(5); // wait for COG to become ready pq.printf("waiting..."); while (this->EPD_Pin_BUSY) { } pq.printf(" OK!\n"); // channel select wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, CU8(0x70, 0x01), 2); wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, this->channel_select, this->channel_select_length); // DC/DC frequency wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, CU8(0x70, 0x06), 2); wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, CU8(0x72, 0xff), 2); // high power mode osc wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, CU8(0x70, 0x07), 2); wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, CU8(0x72, 0x9d), 2); // disable ADC wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, CU8(0x70, 0x08), 2); wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, CU8(0x72, 0x00), 2); // Vcom level wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, CU8(0x70, 0x09), 2); wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, CU8(0x72, 0xd0, 0x00), 3); // gate and source voltage levels wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, CU8(0x70, 0x04), 2); wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, this->gate_source, this->gate_source_length); this->EPD_Pin_PWM = 0.5; wait_ms(5); // pwm toggle >= 5ms // driver latch on wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, CU8(0x70, 0x03), 2); wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, CU8(0x72, 0x01), 2); // driver latch off wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, CU8(0x70, 0x03), 2); wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, CU8(0x72, 0x00), 2); wait_ms(5); // charge pump positive voltage on wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, CU8(0x70, 0x05), 2); wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, CU8(0x72, 0x01), 2); // final delay before PWM off wait_ms(30); this->EPD_Pin_PWM = 0; // charge pump negative voltage on wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, CU8(0x70, 0x05), 2); wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, CU8(0x72, 0x03), 2); wait_ms(30); // Vcom driver on wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, CU8(0x70, 0x05), 2); wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, CU8(0x72, 0x0f), 2); wait_ms(30); // output enable to disable wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, CU8(0x70, 0x02), 2); wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, CU8(0x72, 0x24), 2); } void EPD_Class::end() { // dummy frame //this->frame_fixed(0x55, EPD_normal); // dummy line and border if (EPD_1_44 == this->size) { // only for 1.44" EPD this->line(0x7fffu, 0, 0xaa, false, EPD_normal); wait_ms(250); } else { // all other display sizes this->line(0x7fffu, 0, 0x55, false, EPD_normal); wait_ms(25); this->EPD_Pin_BORDER = 0; wait_ms(250); this->EPD_Pin_BORDER = 1; } SPI_on(); // latch reset turn on wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, CU8(0x70, 0x03), 2); wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, CU8(0x72, 0x01), 2); // output enable off wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, CU8(0x70, 0x02), 2); wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, CU8(0x72, 0x05), 2); // Vcom power off wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, CU8(0x70, 0x05), 2); wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, CU8(0x72, 0x0e), 2); // power off negative charge pump wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, CU8(0x70, 0x05), 2); wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, CU8(0x72, 0x02), 2); // discharge wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, CU8(0x70, 0x04), 2); wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, CU8(0x72, 0x0c), 2); wait_ms(120); // all charge pumps off wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, CU8(0x70, 0x05), 2); wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, CU8(0x72, 0x00), 2); // turn of osc wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, CU8(0x70, 0x07), 2); wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, CU8(0x72, 0x0d), 2); // discharge internal - 1 wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, CU8(0x70, 0x04), 2); wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, CU8(0x72, 0x50), 2); wait_ms(40); // discharge internal - 2 wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, CU8(0x70, 0x04), 2); wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, CU8(0x72, 0xA0), 2); wait_ms(40); // discharge internal - 3 wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, CU8(0x70, 0x04), 2); wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, CU8(0x72, 0x00), 2); // turn of power and all signals // wait_ms(10); this->EPD_Pin_RESET = 0; this->EPD_Pin_PANEL_ON = 0; this->EPD_Pin_BORDER = 0; // discharge pulse this->EPD_Pin_DISCHARGE = 1; wait_ms(250); this->EPD_Pin_DISCHARGE = 0; EPD_Pin_EPD_CS = 1; } // convert a temperature in Celcius to // the scale factor for frame_*_repeat methods int EPD_Class::temperature_to_factor_10x(int temperature) { if (temperature <= -10) { return 170; } else if (temperature <= -5) { return 120; } else if (temperature <= 5) { return 80; } else if (temperature <= 10) { return 40; } else if (temperature <= 15) { return 30; } else if (temperature <= 20) { return 20; } else if (temperature <= 40) { return 10; } return 7; } // One frame of data is the number of lines * rows. For example: // The 1.44” frame of data is 96 lines * 128 dots. // The 2” frame of data is 96 lines * 200 dots. // The 2.7” frame of data is 176 lines * 264 dots. // the image is arranged by line which matches the display size // so smallest would have 96 * 32 bytes void EPD_Class::frame_fixed(uint8_t fixed_value, EPD_stage stage, int from_line, int to_line) { for (uint8_t line = from_line; line < to_line; line++) { this->line(line, 0, fixed_value, false, stage); } } void EPD_Class::frame_data(const uint8_t *image, EPD_stage stage, int from_line, int to_line) { for (uint8_t line = from_line; line < to_line; line++) { this->line(line, &image[line * this->bytes_per_line], 0, true, stage); } } void EPD_Class::frame_fixed_repeat(uint8_t fixed_value, EPD_stage stage, int from_line, int to_line) { long stage_time = this->factored_stage_time; do { unsigned long t_start = timer.read_ms(); this->frame_fixed(fixed_value, stage, from_line, to_line); unsigned long t_end = timer.read_ms(); if (t_end > t_start) { stage_time -= t_end - t_start; } else { stage_time -= t_start - t_end + 1 + ULONG_MAX; } } while (stage_time > 0); } void EPD_Class::frame_data_repeat(const uint8_t *image, EPD_stage stage, int from_line, int to_line) { long stage_time = this->factored_stage_time; do { unsigned long t_start = timer.read_ms(); this->frame_data(image, stage, from_line, to_line); unsigned long t_end = timer.read_ms(); if (t_end > t_start) { stage_time -= t_end - t_start; } else { stage_time -= t_start - t_end + 1 + ULONG_MAX; } } while (stage_time > 0); } void EPD_Class::line(uint16_t line, const uint8_t *data, uint8_t fixed_value, bool read_progmem, EPD_stage stage) { // charge pump voltage levels SPI_on(); wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, CU8(0x70, 0x04), 2); wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, this->gate_source, this->gate_source_length); // send data wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, CU8(0x70, 0x0a), 2); wait_us(10); // CS low this->EPD_Pin_EPD_CS = 0; SPI_put_wait(0x72, this->EPD_Pin_BUSY); // even pixels for (uint16_t b = this->bytes_per_line; b > 0; --b) { if (0 != data) { uint8_t pixels = data[b - 1] & 0xaa; switch(stage) { case EPD_compensate: // B -> W, W -> B (Current Image) pixels = 0xaa | ((pixels ^ 0xaa) >> 1); break; case EPD_white: // B -> N, W -> W (Current Image) pixels = 0x55 + ((pixels ^ 0xaa) >> 1); break; case EPD_inverse: // B -> N, W -> B (New Image) pixels = 0x55 | (pixels ^ 0xaa); break; case EPD_normal: // B -> B, W -> W (New Image) pixels = 0xaa | (pixels >> 1); break; } SPI_put_wait(pixels, this->EPD_Pin_BUSY); //wait_us(1); } else { SPI_put_wait(fixed_value, this->EPD_Pin_BUSY); //wait_ms(1); } } // scan line for (uint16_t b = 0; b < this->bytes_per_scan; ++b) { if (line / 4 == b) { SPI_put_wait(0xc0 >> (2 * (line & 0x03)), this->EPD_Pin_BUSY); } else { SPI_put_wait(0x00, this->EPD_Pin_BUSY); } //wait_ms(10); } // odd pixels for (uint16_t b = 0; b < this->bytes_per_line; ++b) { if (0 != data) { uint8_t pixels = data[b] & 0x55; switch(stage) { case EPD_compensate: // B -> W, W -> B (Current Image) pixels = 0xaa | (pixels ^ 0x55); break; case EPD_white: // B -> N, W -> W (Current Image) pixels = 0x55 + (pixels ^ 0x55); break; case EPD_inverse: // B -> N, W -> B (New Image) pixels = 0x55 | ((pixels ^ 0x55) << 1); break; case EPD_normal: // B -> B, W -> W (New Image) pixels = 0xaa | pixels; break; } uint8_t p1 = (pixels >> 6) & 0x03; uint8_t p2 = (pixels >> 4) & 0x03; uint8_t p3 = (pixels >> 2) & 0x03; uint8_t p4 = (pixels >> 0) & 0x03; pixels = (p1 << 0) | (p2 << 2) | (p3 << 4) | (p4 << 6); SPI_put_wait(pixels, this->EPD_Pin_BUSY); } else { SPI_put_wait(fixed_value, this->EPD_Pin_BUSY); } //wait_ms(10); } if (this->filler) { SPI_put_wait(0x00, this->EPD_Pin_BUSY); } // CS high this->EPD_Pin_EPD_CS = 1; // output data to panel wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, CU8(0x70, 0x02), 2); wait_us(10); SPI_send(this->EPD_Pin_EPD_CS, CU8(0x72, 0x2f), 2); } static void SPI_on() { wait_us(10); } static void SPI_put(uint8_t c) { spi.write(c); } static void SPI_put_wait(uint8_t c, DigitalIn busy_pin) { SPI_put(c); // wait for COG ready while (1 == busy_pin) { } } static void SPI_send(DigitalOut cs_pin, const uint8_t *buffer, uint16_t length) { // CS low cs_pin = 0; // send all data for (uint16_t i = 0; i < length; ++i) { SPI_put(*buffer++); } // CS high cs_pin = 1; }