optimize sending custom chars, one write operation now

This commit is contained in:
2026-06-14 11:55:14 +02:00
parent 8bea9be551
commit 804e477d50
2 changed files with 11 additions and 4 deletions

View File

@@ -59,11 +59,10 @@ void lcd_set_cursor(struct lcd_t *lcd, const uint8_t row, const uint8_t col) {
lcd_write(lcd, cmdbuf, sizeof(cmdbuf));
}
/* reconsider so im not writing every time. prepend custom chars to the write buffer? */
void lcd_set_custom_char(struct lcd_t *lcd, const uint8_t index, const lcd_glyph_t *glyph) {
uint8_t cmdbuf[] = {254, 78, index, 0, 0, 0, 0, 0, 0, 0, 0};
memcpy(&cmdbuf[3], glyph, sizeof(lcd_glyph_t));
lcd_write(lcd, cmdbuf, sizeof(cmdbuf));
memcpy(lcd->ccharbuf[index], cmdbuf, sizeof(cmdbuf));
}
/* writes string to write buffer at calculated pos, we trust it to be null terminated */
@@ -104,7 +103,8 @@ inline void lcd_flush_buf(struct lcd_t *lcd) {
memcpy(&lcd->writebuf[0], set_disp, 4);
memcpy(&lcd->writebuf[2 * LCD_COLS + 4], set_disp, 4);
lcd->writebuf[2 * LCD_COLS + 7] = 3; // overwrite set cursor c1 l1 to c1 l3
lcd_write(lcd, (const uint8_t *)lcd->writebuf, sizeof(lcd->writebuf));
// hacky, relies on charbuf being before writebuf in the lcd struct. we start at the charbuf pointer and write both at the same time
lcd_write(lcd, (const uint8_t *)lcd->ccharbuf, sizeof(lcd->ccharbuf) + sizeof(lcd->writebuf));
}
// i have a whole flushbuf func to avoid too many writes, but im writing on every bar, need to rethink this.
@@ -131,6 +131,12 @@ int lcd_init(struct lcd_t *lcd) {
tcflush(lcd->fd, TCIFLUSH);
tcsetattr(lcd->fd, TCSANOW, &term);
// zero out custom chars
for (uint8_t i = 0; i < 8; i++) {
const uint8_t charbuf[] = {254, 78, i, 0, 0, 0, 0, 0, 0, 0, 0};
memcpy(lcd->ccharbuf[i], charbuf, sizeof(charbuf));
}
lcd_clear_buf(lcd);
const uint8_t cmdbuf[] = {254, 75, 254, 84};
lcd_write(lcd, cmdbuf, sizeof(cmdbuf));