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stm32l1: lcd: Basic LCD configure functions.

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This commit is contained in:
Nikolay Merinov 2014-03-04 01:25:36 +06:00 committed by Karl Palsson
parent 553a14f21d
commit ec29bd7f48
2 changed files with 132 additions and 5 deletions
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19
include/libopencm3/stm32/l1/lcd.h
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@ -206,10 +206,25 @@
BEGIN_DECLS
void lcd_enable(void);
void lcd_wait_step_up_ready(void);
void lcd_wait_for_update_ready(void);
void lcd_update(void);
void lcd_wait_for_lcd_enabled(void);
void lcd_wait_for_step_up_ready(void);
void lcd_wait_for_update_ready(void);
int lcd_is_enabled(void);
int lcd_is_step_up_ready(void);
int lcd_is_for_update_ready(void);
void lcd_set_contrast(uint8_t contrast);
void lcd_set_bias(uint8_t bias);
void lcd_set_duty(uint8_t duty);
void lcd_set_prescaler(uint8_t ps);
void lcd_set_divider(uint8_t div);
void lcd_enable_segment_multiplexing(void);
void lcd_disable_segment_multiplexing(void);
void lcd_set_refresh_frequency(uint32_t frequency);
END_DECLS
#endif

118
lib/stm32/l1/lcd.c
View File

@ -18,14 +18,24 @@
*/
#include <libopencm3/stm32/l1/lcd.h>
#include <libopencm3/stm32/rcc.h>
void lcd_enable(void)
{
LCD_CR |= LCD_CR_LCDEN;
}
void lcd_update(void)
{
LCD_SR |= LCD_SR_UDR;
}
void lcd_wait_for_lcd_enabled(void)
{
while ((LCD_SR & LCD_SR_ENS) == 0);
}
void lcd_wait_step_up_ready(void)
void lcd_wait_for_step_up_ready(void)
{
while ((LCD_SR & LCD_SR_RDY) == 0);
}
@ -35,8 +45,110 @@ void lcd_wait_for_update_ready(void)
while ((LCD_SR & LCD_SR_UDR) != 0);
}
void lcd_update(void)
int lcd_is_enabled(void)
{
LCD_SR |= LCD_SR_UDR;
return ((LCD_SR & LCD_SR_ENS) != 0);
}
int lcd_is_step_up_ready(void)
{
return ((LCD_SR & LCD_SR_RDY) != 0);
}
int lcd_is_for_update_ready(void)
{
return ((LCD_SR & LCD_SR_UDR) == 0);
}
void lcd_set_contrast(uint8_t contrast)
{
LCD_FCR &= ~(LCD_FCR_CC_MASK << LCD_FCR_CC_SHIFT);
LCD_FCR |= contrast << LCD_FCR_CC_SHIFT;
}
void lcd_set_bias(uint8_t bias)
{
LCD_CR &= ~(LCD_CR_BIAS_MASK << LCD_CR_BIAS_SHIFT);
LCD_CR |= bias << LCD_CR_BIAS_SHIFT;
}
void lcd_set_duty(uint8_t duty)
{
LCD_CR &= ~(LCD_CR_DUTY_MASK << LCD_CR_DUTY_SHIFT);
LCD_CR |= duty << LCD_CR_DUTY_SHIFT;
}
void lcd_set_prescaler(uint8_t ps)
{
LCD_FCR &= ~(LCD_FCR_PS_MASK << LCD_FCR_PS_SHIFT);
LCD_FCR |= ps << LCD_FCR_PS_SHIFT;
}
void lcd_set_divider(uint8_t div)
{
LCD_FCR &= ~(LCD_FCR_DIV_MASK << LCD_FCR_DIV_SHIFT);
LCD_FCR |= div << LCD_FCR_DIV_SHIFT;
}
void lcd_enable_segment_multiplexing(void)
{
LCD_CR |= LCD_CR_MUX_SEG;
}
void lcd_disable_segment_multiplexing(void)
{
LCD_CR &= ~LCD_CR_MUX_SEG;
}
void lcd_set_refresh_frequency(uint32_t frequency)
{
uint32_t duty, lcd_clock;
switch ((LCD_CR >> LCD_CR_DUTY_SHIFT) & LCD_CR_DUTY_MASK) {
case LCD_CR_DUTY_STATIC:
duty = 1;
break;
case LCD_CR_DUTY_1_2:
duty = 2;
break;
case LCD_CR_DUTY_1_3:
duty = 3;
break;
case LCD_CR_DUTY_1_4:
duty = 4;
break;
case LCD_CR_DUTY_1_8:
duty = 8;
break;
default:
/* Incorrect duty */
return;
}
switch ((RCC_CSR >> RCC_CSR_RTCSEL_SHIFT) & RCC_CSR_RTCSEL_MASK) {
case RCC_CSR_RTCSEL_LSE:
lcd_clock = 32786;
break;
case RCC_CSR_RTCSEL_LSI:
lcd_clock = 37000;
break;
case RCC_CSR_RTCSEL_HSI:
lcd_clock = 16000000;
break;
default:
/* RCC Clock not selected */
return;
}
/* PS * DIV = lcd_clock/(duty * freq) */
uint32_t ps_mul_div = lcd_clock / (duty * frequency);
int div, ps = 0;
while (ps_mul_div > 32) {
ps_mul_div >>= 1;
ps++;
}
div = ps_mul_div - 16;
lcd_set_prescaler(ps);
lcd_set_divider(div);
}