reform

oled.c (7621B)

---

 /*
   MNT Reform 2.0 Keyboard Firmware
   See keyboard.c for Copyright
   SPDX-License-Identifier: MIT
 */
 
 // OLED (SSD1306) rendering code. The OLED is interfaced via I2C.
 
 #include "oled.h"
 #include "i2c.h"
 #include <stdio.h>
 #include <string.h>
 #include <avr/pgmspace.h>
 #include "gfx/font.c"
 
 struct CharacterMatrix display;
 int oledbrt = 0;
 
 // Write command sequence.
 // Returns true on success.
 static inline bool _send_cmd1(uint8_t cmd) {
   bool res = false;
 
   if (i2c_start_write(SSD1306_ADDRESS)) {
     // failed to start write
     goto done;
   }
 
   if (i2c_master_write(0x0 /* command byte follows */)) {
     // failed to write control byte
     goto done;
   }
 
   if (i2c_master_write(cmd)) {
     //  failed to write command
     goto done;
   }
   res = true;
 done:
   i2c_master_stop();
   return res;
 }
 
 // Write 2-byte command sequence.
 // Returns true on success
 static inline bool _send_cmd2(uint8_t cmd, uint8_t opr) {
   if (!_send_cmd1(cmd)) {
     //return false;
   }
   return _send_cmd1(opr);
 }
 
 // Write 3-byte command sequence.
 // Returns true on success
 static inline bool _send_cmd3(uint8_t cmd, uint8_t opr1, uint8_t opr2) {
   if (!_send_cmd1(cmd)) {
     //return false;
   }
   if (!_send_cmd1(opr1)) {
     //return false;
   }
   return _send_cmd1(opr2);
 }
 
 #define send_cmd1(c) if (!_send_cmd1(c)) {goto done;}
 #define send_cmd2(c,o) if (!_send_cmd2(c,o)) {goto done;}
 #define send_cmd3(c,o1,o2) if (!_send_cmd3(c,o1,o2)) {goto done;}
 
 void oled_clear(void) {
   matrix_clear(&display);
 
   // Clear all of the display bits (there can be random noise
   // in the RAM on startup)
   send_cmd3(PageAddr, 0, (DisplayHeight / 8) - 1);
   send_cmd3(ColumnAddr, 0, DisplayWidth - 1);
 
   if (i2c_start_write(SSD1306_ADDRESS)) {
     goto done;
   }
   if (i2c_master_write(0x40)) {
     // Data mode
     goto done;
   }
   for (uint8_t row = 0; row < MatrixRows; ++row) {
     for (uint8_t col = 0; col < DisplayWidth; ++col) {
       i2c_master_write(0);
     }
   }
 
   display.dirty = false;
 
 done:
   i2c_master_stop();
 }
 
 bool gfx_init(bool rotate) {
   bool success = false;
 	rotate = false; // FIXME
 
   i2c_master_init();
   send_cmd1(DisplayOff);
   send_cmd2(SetDisplayClockDiv, 0x80);
   send_cmd2(SetMultiPlex, DisplayHeight - 1);
 
   send_cmd2(SetDisplayOffset, 0);
 
   send_cmd1(SetStartLine | 0x0);
   send_cmd2(SetChargePump, 0x14 /* Enable */);
   send_cmd2(SetMemoryMode, 0 /* horizontal addressing */);
 
   if (rotate) {
     // the following Flip the display orientation 180 degrees
     send_cmd1(SegRemap);
     send_cmd1(ComScanInc);
   } else {
     // Flips the display orientation 0 degrees
     send_cmd1(SegRemap | 0x1);
     send_cmd1(ComScanDec);
   }
 
   send_cmd2(SetComPins, 0x2);
   send_cmd2(SetContrast, 0x8f);
   send_cmd2(SetPreCharge, 0xf1);
   send_cmd2(SetVComDetect, 0x40);
   send_cmd1(DisplayAllOnResume);
   send_cmd1(NormalDisplay);
   send_cmd1(DeActivateScroll);
   send_cmd1(DisplayOn);
 
   send_cmd2(SetContrast, 0); // Dim
 
   oled_clear();
 
   success = true;
 
   gfx_flush();
 
 done:
   return success;
 }
 
 bool gfx_off(void) {
   bool success = false;
 
   //send_cmd1(InvertDisplay);
   send_cmd1(DisplayOff);
   success = true;
 
 done:
   return success;
 }
 
 bool gfx_on(void) {
   bool success = false;
 
   send_cmd1(NormalDisplay);
   send_cmd1(DisplayOn);
   success = true;
 
 done:
   return success;
 }
 
 void gfx_clear(void) {
   for (int y=0; y<4; y++) {
     for (int x=0; x<21; x++) {
       gfx_poke(x,y,' ');
     }
   }
   gfx_clear_invert();
 }
 
 void gfx_contrast(int c) {
   send_cmd2(SetContrast, c);
 done:
   return;
 }
 
 void matrix_write_char_inner(struct CharacterMatrix *matrix, uint8_t c) {
   *matrix->cursor = c;
   ++matrix->cursor;
 
   if (matrix->cursor - &matrix->display[0][0] == sizeof(matrix->display)) {
     // We went off the end; scroll the display upwards by one line
     memmove(&matrix->display[0], &matrix->display[1],
             MatrixCols * (MatrixRows - 1));
     matrix->cursor = &matrix->display[MatrixRows - 1][0];
     memset(matrix->cursor, ' ', MatrixCols);
   }
 }
 
 void matrix_write_char(struct CharacterMatrix *matrix, uint8_t c) {
   matrix->dirty = true;
 
   if (c == '\n') {
     // Clear to end of line from the cursor and then move to the
     // start of the next line
     uint8_t cursor_col = (matrix->cursor - &matrix->display[0][0]) % MatrixCols;
 
     while (cursor_col++ < MatrixCols) {
       matrix_write_char_inner(matrix, ' ');
     }
     return;
   }
 
   matrix_write_char_inner(matrix, c);
 }
 
 void gfx_poke(uint8_t x, uint8_t y, uint8_t c) {
 	display.display[y][x] = c;
 }
 
 void gfx_poke_str(uint8_t x, uint8_t y, char* str) {
   int len = strlen(str);
   if (len>21) len = 21;
   // clip
   if (y<0 || y>3) return;
 
   for (int xx=x; xx<x+len && xx<21; xx++) {
     if (xx>=0 && xx<21) {
       display.display[y][xx] = (uint8_t)str[xx-x];
     }
   }
 }
 
 void gfx_write_char(uint8_t c) {
   matrix_write_char(&display, c);
 }
 
 void matrix_write(struct CharacterMatrix *matrix, const char *data) {
   const char *end = data + strlen(data);
   while (data < end) {
     matrix_write_char(matrix, *data);
     ++data;
   }
 }
 
 void matrix_write_ln(struct CharacterMatrix *matrix, const char *data) {
   char data_ln[strlen(data)+2];
   snprintf(data_ln, sizeof(data_ln), "%s\n", data);
   matrix_write(matrix, data_ln);
 }
 
 void gfx_write(const char *data) {
   matrix_write(&display, data);
 }
 
 void matrix_write_P(struct CharacterMatrix *matrix, const char *data) {
   while (true) {
     uint8_t c = pgm_read_byte(data);
     if (c == 0) {
       return;
     }
     matrix_write_char(matrix, c);
     ++data;
   }
 }
 
 void gfx_write_P(const char *data) {
   matrix_write_P(&display, data);
 }
 
 void matrix_clear(struct CharacterMatrix *matrix) {
   memset(matrix->display, ' ', sizeof(matrix->display));
   matrix->cursor = &matrix->display[0][0];
   matrix->dirty = true;
 }
 
 void gfx_clear_screen(void) {
   matrix_clear(&display);
 }
 
 void gfx_clear_invert(void) {
   for (int y=0;y<4;y++) {
     for (int x=0;x<21;x++) {
       display.invert[y][x] = 0;
     }
   }
 }
 
 void gfx_invert_row(uint8_t y) {
   if (y<0 || y>3) return;
   for (int x=0;x<21;x++) {
     display.invert[y][x] = 1;
   }
 }
 
 void matrix_render(struct CharacterMatrix *matrix) {
   gfx_on();
 
   // Move to the home position
   send_cmd3(PageAddr, 0, MatrixRows - 1);
   send_cmd3(ColumnAddr, 0, (MatrixCols * FontWidth) - 1);
 
   if (i2c_start_write(SSD1306_ADDRESS)) {
     //goto done;
   }
   if (i2c_master_write(0x40)) {
     // Data mode
     //goto done;
   }
 
   for (uint8_t row = 0; row < MatrixRows; ++row) {
     for (uint8_t col = 0; col < MatrixCols; ++col) {
       const uint8_t *glyph = font + (matrix->display[row][col] * FontWidth);
       const uint8_t invert = matrix->invert[row][col];
 
       for (uint8_t glyphCol = 0; glyphCol < FontWidth; ++glyphCol) {
         uint8_t colBits = pgm_read_byte(glyph + glyphCol);
         if (invert) colBits = ~colBits;
         i2c_master_write(colBits);
       }
     }
   }
 
   matrix->dirty = false;
 
 done:
   i2c_master_stop();
 }
 
 void matrix_render_direct(uint8_t* bitmap) {
   gfx_on();
 
   // Move to the home position
   send_cmd3(PageAddr, 0, (DisplayHeight / 8) - 1);
   send_cmd3(ColumnAddr, 0, DisplayWidth - 1);
 
   i2c_start_write(SSD1306_ADDRESS);
   i2c_master_write(0x40);
 
   int c = 0;
   for (uint16_t y=0; y<4; y++) {
     for (uint16_t x=0; x<128; x++) {
       i2c_master_write(bitmap[c++]);
     }
   }
 
 done:
   i2c_master_stop();
 }
 
 void gfx_flush(void) {
   matrix_render(&display);
 }
 
 void oled_brightness_inc(void) {
   oledbrt+=10;
   if (oledbrt>=0xff) oledbrt = 0xff;
   gfx_contrast(oledbrt);
 }
 
 void oled_brightness_dec(void) {
   oledbrt-=10;
   if (oledbrt<0) oledbrt = 0;
   gfx_contrast(oledbrt);
 }