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Added standard clock setup routines. 

Thanks to Thomas Otto for pointing out problems with the clock code in
examples and his clock routine implementations. Based on that the most
common clock combination routines were added to the library and all
routines in examples setting up the clock replaced with calls to that
functions.
pull/2/head
Piotr Esden-Tempski 15 years ago
parent
d84c4030b2
commit
d7489ebfbd
7 changed files with 114 additions and 94 deletions
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  1. 22
      examples/mb525/fancyblink/fancyblink.c
  2. 19
      examples/mb525/pwmleds/pwmleds.c
  3. 21
      examples/stm32-h103/fancyblink/fancyblink.c
  4. 18
      examples/stm32-h103/spi/spi.c
  5. 28
      examples/stm32-h103/usart/usart.c
  6. 2
      include/libopenstm32/rcc.h
  7. 98
      lib/rcc.c

22
examples/mb525/fancyblink/fancyblink.c
View File

@ -21,33 +21,17 @@
#include <libopenstm32/rcc.h>
#include <libopenstm32/gpio.h>
/* Set STM32 to 72 MHz. */
void clock_setup(void)
{
/* Select HSI as SYSCLK source. */
rcc_set_sysclk_source(SW_SYSCLKSEL_HSICLK);
rcc_clock_setup_in_hse_8mhz_out_72mhz();
/* Set the PLL multiplication factor to 9. */
rcc_set_pll_multiplication_factor(PLLMUL_PLL_CLK_MUL9);
/* Select HSI/2 as PLL source. */
rcc_set_pll_source(PLLSRC_HSI_CLK_DIV2);
rcc_set_pllxtpre(PLLXTPRE_HSE_CLK_DIV2);
/* Enable PLL oscillator and wait for it to stabilize. */
rcc_osc_on(PLL);
rcc_wait_for_osc_ready(PLL);
/* Enable GPIOC clock. */
rcc_peripheral_enable_clock(&RCC_APB2ENR, IOPCEN);
/* Select PLL as SYSCLK source. */
rcc_set_sysclk_source(SW_SYSCLKSEL_PLLCLK);
}
void gpio_setup(void)
{
/* Enable GPIOC clock. */
rcc_peripheral_enable_clock(&RCC_APB2ENR, IOPCEN);
/* Set GPIO6 (in GPIO port C) to 'output push-pull'. */
gpio_set_mode(GPIOC, GPIO_MODE_OUTPUT_50_MHZ,
GPIO_CNF_OUTPUT_PUSHPULL, GPIO6 | GPIO7 | GPIO8 | GPIO9);

19
examples/mb525/pwmleds/pwmleds.c
View File

@ -236,26 +236,9 @@ static const u16 gamma_table_3_0[] = {
};
#endif
/* Set STM32 to 72 MHz. */
void clock_setup(void)
{
/* Select HSI as SYSCLK source. */
rcc_set_sysclk_source(SW_SYSCLKSEL_HSICLK);
/* Set the PLL multiplication factor to 9. */
rcc_set_pll_multiplication_factor(PLLMUL_PLL_CLK_MUL9);
/* Select HSI/2 as PLL source. */
rcc_set_pll_source(PLLSRC_HSI_CLK_DIV2);
rcc_set_pllxtpre(PLLXTPRE_HSE_CLK_DIV2);
/* Enable PLL oscillator and wait for it to stabilize. */
rcc_osc_on(PLL);
rcc_wait_for_osc_ready(PLL);
/* Select PLL as SYSCLK source. */
rcc_set_sysclk_source(SW_SYSCLKSEL_PLLCLK);
rcc_clock_setup_in_hse_8mhz_out_72mhz();
/* Enable TIM3 clock. */
rcc_peripheral_enable_clock(&RCC_APB1ENR, TIM3EN);

21
examples/stm32-h103/fancyblink/fancyblink.c
View File

@ -23,30 +23,15 @@
/* Set STM32 to 72 MHz. */
void clock_setup(void)
{
/* Select HSI as SYSCLK source. */
rcc_set_sysclk_source(SW_SYSCLKSEL_HSICLK);
rcc_clock_setup_in_hse_8mhz_out_72mhz();
/* Set the PLL multiplication factor to 9. */
rcc_set_pll_multiplication_factor(PLLMUL_PLL_CLK_MUL9);
/* Select HSI/2 as PLL source. */
rcc_set_pll_source(PLLSRC_HSI_CLK_DIV2);
rcc_set_pllxtpre(PLLXTPRE_HSE_CLK_DIV2);
/* Enable PLL oscillator and wait for it to stabilize. */
rcc_osc_on(PLL);
rcc_wait_for_osc_ready(PLL);
/* Enable GPIOC clock. */
rcc_peripheral_enable_clock(&RCC_APB2ENR, IOPCEN);
/* Select PLL as SYSCLK source. */
rcc_set_sysclk_source(SW_SYSCLKSEL_PLLCLK);
}
void gpio_setup(void)
{
/* Enable GPIOC clock. */
rcc_peripheral_enable_clock(&RCC_APB2ENR, IOPCEN);
/* Set GPIO12 (in GPIO port C) to 'output push-pull'. */
gpio_set_mode(GPIOC, GPIO_MODE_OUTPUT_50_MHZ,
GPIO_CNF_OUTPUT_PUSHPULL, GPIO12);

18
examples/stm32-h103/spi/spi.c
View File

@ -21,23 +21,7 @@
void clock_setup(void)
{
/* Select HSI as SYSCLK source. */
rcc_set_sysclk_source(SW_SYSCLKSEL_HSICLK);
/* Set the PLL multiplication factor to 9. */
rcc_set_pll_multiplication_factor(PLLMUL_PLL_CLK_MUL9);
/* Select HSI/2 as PLL source. */
rcc_set_pll_source(PLLSRC_HSI_CLK_DIV2);
rcc_set_pllxtpre(PLLXTPRE_HSE_CLK_DIV2);
/* Enable PLL oscillator and wait for it to stabilize. */
rcc_osc_on(PLL);
rcc_wait_for_osc_ready(PLL);
/* Select PLL as SYSCLK source. */
rcc_set_sysclk_source(SW_SYSCLKSEL_PLLCLK);
rcc_clock_setup_in_hse_8mhz_out_72mhz();
}
void spi_setup(void)

28
examples/stm32-h103/usart/usart.c
View File

@ -23,31 +23,18 @@
void clock_setup(void)
{
/* Select HSI as SYSCLK source. */
rcc_set_sysclk_source(SW_SYSCLKSEL_HSICLK);
rcc_clock_setup_in_hse_8mhz_out_72mhz();
/* Set the PLL multiplication factor to 9. */
rcc_set_pll_multiplication_factor(PLLMUL_PLL_CLK_MUL9);
/* Select HSI/2 as PLL source. */
rcc_set_pll_source(PLLSRC_HSI_CLK_DIV2);
rcc_set_pllxtpre(PLLXTPRE_HSE_CLK_DIV2);
/* Enable PLL oscillator and wait for it to stabilize. */
rcc_osc_on(PLL);
rcc_wait_for_osc_ready(PLL);
/* Select PLL as SYSCLK source. */
rcc_set_sysclk_source(SW_SYSCLKSEL_PLLCLK);
}
/* Enable GPIOC clock. */
rcc_peripheral_enable_clock(&RCC_APB2ENR, IOPCEN);
void usart_setup(void)
{
/* Enable clocks for GPIO port B (for GPIO_USART3_TX) and USART3. */
rcc_peripheral_enable_clock(&RCC_APB2ENR, IOPBEN);
rcc_peripheral_enable_clock(&RCC_APB1ENR, USART3EN);
}
void usart_setup(void)
{
/* Setup GPIO pin GPIO_USART3_TX/GPIO10 on GPIO port B for transmit. */
gpio_set_mode(GPIOB, GPIO_MODE_OUTPUT_50_MHZ,
GPIO_CNF_OUTPUT_ALTFN_PUSHPULL, GPIO_USART3_TX);
@ -66,9 +53,6 @@ void usart_setup(void)
void gpio_setup(void)
{
/* Enable GPIOC clock. */
rcc_peripheral_enable_clock(&RCC_APB2ENR, IOPCEN);
/* Set GPIO12 (in GPIO port C) to 'output push-pull'. */
gpio_set_mode(GPIOC, GPIO_MODE_OUTPUT_2_MHZ,
GPIO_CNF_OUTPUT_PUSHPULL, GPIO12);

2
include/libopenstm32/rcc.h
View File

@ -398,5 +398,7 @@ void rcc_set_ppre2(u32 ppre2);
void rcc_set_ppre1(u32 ppre1);
void rcc_set_hpre(u32 hpre);
u32 rcc_get_system_clock_source(int i);
void rcc_clock_setup_in_hsi_out_64mhz(void);
void rcc_clock_setup_in_hse_8mhz_out_72mhz(void);
#endif

98
lib/rcc.c
View File

@ -323,3 +323,101 @@ u32 rcc_system_clock_source(void)
/* Return the clock source which is used as system clock. */
return ((RCC_CFGR & 0x000c) >> 2);
}
/*
* These functions are setting up the whole clock system for the most common
* input clock and output clock configurations.
*/
void rcc_clock_setup_in_hsi_out_64mhz(void){
/* enable Internal High Speed Oscillator */
rcc_osc_on(HSI);
rcc_wait_for_osc_ready(HSI);
/* Select HSI as SYSCLK source. */
rcc_set_sysclk_source(SW_SYSCLKSEL_HSICLK);
/*
* set prescalers for AHB, ADC, ABP1, ABP2
* make this before touching the PLL (why?)
*/
rcc_set_hpre(HPRE_SYSCLK_NODIV); /* Max 72MHz */
rcc_set_adcpre(ADCPRE_PLCK2_DIV8); /* Max 14MHz */
rcc_set_ppre1(PPRE1_HCLK_DIV2); /* Max 36MHz */
rcc_set_ppre2(PPRE2_HCLK_NODIV); /* Max 72MHz */
/* sysclk is running with 64MHz -> 2 Waitstates
* 0WS from 0-24MHz
* 1WS from 24-48MHz
* 2WS from 48-72MHz
*/
flash_set_ws(FLASH_LATENCY_2WS);
/* Set the PLL multiplication factor to 16.
* -> 8MHz (internal) * 16 (multiplier) / 2 (PLLSRC_HSI_CLK_DIV2) = 64MHz
*/
rcc_set_pll_multiplication_factor(PLLMUL_PLL_CLK_MUL16);
/* Select HSI/2 as PLL source. */
rcc_set_pll_source(PLLSRC_HSI_CLK_DIV2);
/* Enable PLL oscillator and wait for it to stabilize. */
rcc_osc_on(PLL);
rcc_wait_for_osc_ready(PLL);
/* Select PLL as SYSCLK source. */
rcc_set_sysclk_source(SW_SYSCLKSEL_PLLCLK);
}
void rcc_clock_setup_in_hse_8mhz_out_72mhz(void){
/* enable Internal High Speed Oscillator */
rcc_osc_on(HSI);
rcc_wait_for_osc_ready(HSI);
/* Select HSI as SYSCLK source. */
rcc_set_sysclk_source(SW_SYSCLKSEL_HSICLK);
/* enable External High Speed Oscillator 8MHz */
rcc_osc_on(HSE);
rcc_wait_for_osc_ready(HSE);
rcc_set_sysclk_source(SW_SYSCLKSEL_HSECLK);
/* set prescalers for AHB, ADC, ABP1, ABP2
* do this before touching the PLL (why?)
*/
rcc_set_hpre(HPRE_SYSCLK_NODIV); // Max 72MHz
rcc_set_adcpre(ADCPRE_PLCK2_DIV8); // Max 14MHz
rcc_set_ppre1(PPRE1_HCLK_DIV2); // Max 36MHz
rcc_set_ppre2(PPRE2_HCLK_NODIV); // Max 72MHz
/* sysclk runs with 72MHz -> 2 Waitstates
* 0WS from 0-24MHz
* 1WS from 24-48MHz
* 2WS from 48-72MHz
*/
flash_set_ws(FLASH_LATENCY_2WS);
/* Set the PLL multiplication factor to 9.
* -> 8MHz (external) * 9 (multiplier) = 72MHz
*/
rcc_set_pll_multiplication_factor(PLLMUL_PLL_CLK_MUL10);
/* Select HSE as PLL source. */
rcc_set_pll_source(PLLSRC_HSE_CLK);
/* external frequency undivided before entering pll
* (only valid/needed for HSE)
*/
rcc_set_pllxtpre(PLLXTPRE_HSE_CLK);
/* Enable PLL oscillator and wait for it to stabilize. */
rcc_osc_on(PLL);
rcc_wait_for_osc_ready(PLL);
/* Select PLL as SYSCLK source. */
rcc_set_sysclk_source(SW_SYSCLKSEL_PLLCLK);
}

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