diff options
Diffstat (limited to 'stm/lcd.c')
| -rw-r--r-- | stm/lcd.c | 202 |
1 files changed, 202 insertions, 0 deletions
diff --git a/stm/lcd.c b/stm/lcd.c new file mode 100644 index 0000000000..bbd171991b --- /dev/null +++ b/stm/lcd.c @@ -0,0 +1,202 @@ +#include <stm32f4xx_gpio.h> +#include "systick.h" +#include "lcd.h" +#include "font_petme128_8x8.h" + +#define PYB_LCD_PORT (GPIOA) +#define PYB_LCD_CS1_PIN (GPIO_Pin_0) +#define PYB_LCD_RST_PIN (GPIO_Pin_1) +#define PYB_LCD_A0_PIN (GPIO_Pin_2) +#define PYB_LCD_SCL_PIN (GPIO_Pin_3) +#define PYB_LCD_SI_PIN (GPIO_Pin_4) + +#define LCD_INSTR (0) +#define LCD_DATA (1) + +static void lcd_out(int instr_data, uint8_t i) { + sys_tick_delay_ms(0); + PYB_LCD_PORT->BSRRH = PYB_LCD_CS1_PIN; // CS=0; enable + if (instr_data == LCD_INSTR) { + PYB_LCD_PORT->BSRRH = PYB_LCD_A0_PIN; // A0=0; select instr reg + } else { + PYB_LCD_PORT->BSRRL = PYB_LCD_A0_PIN; // A0=1; select data reg + } + // send byte bigendian, latches on rising clock + for (uint32_t n = 0; n < 8; n++) { + sys_tick_delay_ms(0); + PYB_LCD_PORT->BSRRH = PYB_LCD_SCL_PIN; // SCL=0 + if ((i & 0x80) == 0) { + PYB_LCD_PORT->BSRRH = PYB_LCD_SI_PIN; // SI=0 + } else { + PYB_LCD_PORT->BSRRL = PYB_LCD_SI_PIN; // SI=1 + } + i <<= 1; + sys_tick_delay_ms(0); + PYB_LCD_PORT->BSRRL = PYB_LCD_SCL_PIN; // SCL=1 + } + PYB_LCD_PORT->BSRRL = PYB_LCD_CS1_PIN; // CS=1; disable + + /* + in Python, native types: + CS1_PIN(const) = 0 + n = int(0) + delay_ms(0) + PORT[word:BSRRH] = 1 << CS1_PIN + for n in range(0, 8): + delay_ms(0) + PORT[word:BSRRH] = 1 << SCL_PIN + if i & 0x80 == 0: + PORT[word:BSRRH] = 1 << SI_PIN + else: + PORT[word:BSRRL] = 1 << SI_PIN + i <<= 1 + delay_ms(0) + PORT[word:BSRRL] = 1 << SCL_PIN + */ +} + +/* +static void lcd_data_out(uint8_t i) { + delay_ms(0); + PYB_LCD_PORT->BSRRH = PYB_LCD_CS1_PIN; // CS=0; enable + PYB_LCD_PORT->BSRRL = PYB_LCD_A0_PIN; // A0=1; select data reg + // send byte bigendian, latches on rising clock + for (uint32_t n = 0; n < 8; n++) { + delay_ms(0); + PYB_LCD_PORT->BSRRH = PYB_LCD_SCL_PIN; // SCL=0 + if ((i & 0x80) == 0) { + PYB_LCD_PORT->BSRRH = PYB_LCD_SI_PIN; // SI=0 + } else { + PYB_LCD_PORT->BSRRL = PYB_LCD_SI_PIN; // SI=1 + } + i <<= 1; + delay_ms(0); + PYB_LCD_PORT->BSRRL = PYB_LCD_SCL_PIN; // SCL=1 + } + PYB_LCD_PORT->BSRRL = PYB_LCD_CS1_PIN; // CS=1; disable +} +*/ + +#define LCD_BUF_W (16) +#define LCD_BUF_H (4) + +char lcd_buffer[LCD_BUF_W * LCD_BUF_H]; +int lcd_line; +int lcd_column; +int lcd_next_line; + +void lcd_init() { + // set the outputs high + PYB_LCD_PORT->BSRRL = PYB_LCD_CS1_PIN; + PYB_LCD_PORT->BSRRL = PYB_LCD_RST_PIN; + PYB_LCD_PORT->BSRRL = PYB_LCD_A0_PIN; + PYB_LCD_PORT->BSRRL = PYB_LCD_SCL_PIN; + PYB_LCD_PORT->BSRRL = PYB_LCD_SI_PIN; + + // make them push/pull outputs + GPIO_InitTypeDef GPIO_InitStructure; + GPIO_InitStructure.GPIO_Pin = PYB_LCD_CS1_PIN | PYB_LCD_RST_PIN | PYB_LCD_A0_PIN | PYB_LCD_SCL_PIN | PYB_LCD_SI_PIN; + GPIO_InitStructure.GPIO_Mode = GPIO_Mode_OUT; + GPIO_InitStructure.GPIO_Speed = GPIO_Speed_2MHz; + GPIO_InitStructure.GPIO_OType = GPIO_OType_PP; + GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL; + GPIO_Init(PYB_LCD_PORT, &GPIO_InitStructure); + + // init the LCD + sys_tick_delay_ms(1); // wait a bit + PYB_LCD_PORT->BSRRH = PYB_LCD_RST_PIN; // RST=0; reset + sys_tick_delay_ms(1); // wait for reset; 2us min + PYB_LCD_PORT->BSRRL = PYB_LCD_RST_PIN; // RST=1; enable + sys_tick_delay_ms(1); // wait for reset; 2us min + lcd_out(LCD_INSTR, 0xa0); // ADC select, normal + lcd_out(LCD_INSTR, 0xc8); // common output mode select, reverse + lcd_out(LCD_INSTR, 0xa2); // LCD bias set, 1/9 bias + lcd_out(LCD_INSTR, 0x2f); // power control set, 0b111=(booster on, vreg on, vfollow on) + lcd_out(LCD_INSTR, 0x21); // v0 voltage regulator internal resistor ratio set, 0b001=small + lcd_out(LCD_INSTR, 0x81); // electronic volume mode set + lcd_out(LCD_INSTR, 0x34); // electronic volume register set, 0b110100 + lcd_out(LCD_INSTR, 0x40); // display start line set, 0 + lcd_out(LCD_INSTR, 0xaf); // LCD display, on + + // clear display + for (int page = 0; page < 4; page++) { + lcd_out(LCD_INSTR, 0xb0 | page); // page address set + lcd_out(LCD_INSTR, 0x10); // column address set upper + lcd_out(LCD_INSTR, 0x00); // column address set lower + for (int i = 0; i < 128; i++) { + lcd_out(LCD_DATA, 0x00); + } + } + + for (int i = 0; i < LCD_BUF_H * LCD_BUF_W; i++) { + lcd_buffer[i] = ' '; + } + lcd_line = 0; + lcd_column = 0; + lcd_next_line = 0; +} + +void lcd_print_strn(const char *str, unsigned int len) { + int redraw_min = lcd_line * LCD_BUF_W + lcd_column; + int redraw_max = redraw_min; + int did_new_line = 0; + for (; len > 0; len--, str++) { + // move to next line if needed + if (lcd_next_line) { + if (lcd_line + 1 < LCD_BUF_H) { + lcd_line += 1; + } else { + lcd_line = LCD_BUF_H - 1; + for (int i = 0; i < LCD_BUF_W * (LCD_BUF_H - 1); i++) { + lcd_buffer[i] = lcd_buffer[i + LCD_BUF_W]; + } + for (int i = 0; i < LCD_BUF_W; i++) { + lcd_buffer[LCD_BUF_W * (LCD_BUF_H - 1) + i] = ' '; + } + redraw_min = 0; + redraw_max = LCD_BUF_W * LCD_BUF_H; + } + lcd_next_line = 0; + lcd_column = 0; + did_new_line = 1; + } + if (*str == '\n') { + lcd_next_line = 1; + } else if (lcd_column >= LCD_BUF_W) { + lcd_next_line = 1; + str -= 1; + len += 1; + } else { + lcd_buffer[lcd_line * LCD_BUF_W + lcd_column] = *str; + lcd_column += 1; + int max = lcd_line * LCD_BUF_W + lcd_column; + if (max > redraw_max) { + redraw_max = max; + } + } + } + + int last_page = -1; + for (int i = redraw_min; i < redraw_max; i++) { + int page = i / LCD_BUF_W; + if (page != last_page) { + int offset = 8 * (i - (page * LCD_BUF_W)); + lcd_out(LCD_INSTR, 0xb0 | page); // page address set + lcd_out(LCD_INSTR, 0x10 | ((offset >> 4) & 0x0f)); // column address set upper + lcd_out(LCD_INSTR, 0x00 | (offset & 0x0f)); // column address set lower + last_page = page; + } + int chr = lcd_buffer[i]; + if (chr < 32 || chr > 126) { + chr = 127; + } + const uint8_t *chr_data = &font_petme128_8x8[(chr - 32) * 8]; + for (int i = 0; i < 8; i++) { + lcd_out(LCD_DATA, chr_data[i]); + } + } + + if (did_new_line) { + sys_tick_delay_ms(200); + } +} |