void rcc_clock_setup_hsi(const clock_scale_t *clock)
{
/* Enable internal high-speed oscillator. */
rcc_osc_on(HSI);
rcc_wait_for_osc_ready(HSI);
/* Select HSI as SYSCLK source. */
rcc_set_sysclk_source(RCC_CFGR_SW_HSI); /* XXX: se cayo */
rcc_wait_for_sysclk_status(HSI);
rcc_osc_off(PLL);
rcc_wait_for_osc_not_ready(PLL);
rcc_set_pll_source(clock->pllsrc);
rcc_set_main_pll_hsi(clock->pll);
/* Enable PLL oscillator and wait for it to stabilize. */
rcc_osc_on(PLL);
rcc_wait_for_osc_ready(PLL);
/*
* Set prescalers for AHB, ADC, ABP1, ABP2.
* Do this before touching the PLL (TODO: why?).
*/
rcc_set_hpre(clock->hpre);
rcc_set_ppre2(clock->ppre2);
rcc_set_ppre1(clock->ppre1);
/* Configure flash settings. */
flash_set_ws(clock->flash_config);
/* Select PLL as SYSCLK source. */
rcc_set_sysclk_source(RCC_CFGR_SW_PLL); /* XXX: se cayo */
/* Wait for PLL clock to be selected. */
rcc_wait_for_sysclk_status(PLL);
/* Set the peripheral clock frequencies used. */
rcc_ppre1_frequency = clock->apb1_frequency;
rcc_ppre2_frequency = clock->apb2_frequency;
}
static inline void rcc_clock_setup_hse(const my_clock_scale_t *clock)
{
/* Enable internal high-speed oscillator. */
rcc_osc_on(HSE);
rcc_wait_for_osc_ready(HSE);
/* Select HSE as SYSCLK source. */
rcc_set_sysclk_source(RCC_CFGR_SW_HSE);
rcc_wait_for_sysclk_status(HSE);
rcc_osc_off(PLL);
rcc_wait_for_osc_not_ready(PLL);
rcc_set_pll_source(clock->pllsrc);
rcc_set_main_pll_hse(clock->pll);
RCC_CFGR2 = (clock->pllpre << RCC_CFGR2_PREDIV_SHIFT);
/* Enable PLL oscillator and wait for it to stabilize. */
rcc_osc_on(PLL);
rcc_wait_for_osc_ready(PLL);
rcc_set_hpre(clock->hpre);
rcc_set_ppre2(clock->ppre2);
rcc_set_ppre1(clock->ppre1);
/* Configure flash settings. */
flash_set_ws(clock->flash_config);
/* Select PLL as SYSCLK source. */
rcc_set_sysclk_source(RCC_CFGR_SW_PLL);
/* Wait for PLL clock to be selected. */
rcc_wait_for_sysclk_status(PLL);
/* Set the peripheral clock frequencies used. */
rcc_apb1_frequency = clock->apb1_frequency;
rcc_apb2_frequency = clock->apb2_frequency;
}
static void clk_tree_setup(void)
{
/* cf. rcc_clock_setup_in_hsi_out_48mhz */
rcc_osc_on(RCC_HSI);
rcc_wait_for_osc_ready(RCC_HSI);
rcc_set_sysclk_source(RCC_HSI);
rcc_osc_on(RCC_HSE);
rcc_wait_for_osc_ready(RCC_HSE);
rcc_osc_off(RCC_PLL);
rcc_wait_for_osc_not_ready(RCC_PLL);
flash_set_ws(FLASH_ACR_LATENCY_024_048MHZ);
#ifdef NUCLEO
rcc_set_pll_multiplication_factor(RCC_CFGR_PLLMUL_MUL6);
#else
/* 16MHz * 3 = 48MHz */
rcc_set_pll_multiplication_factor(RCC_CFGR_PLLMUL_MUL3);
#endif
rcc_set_pll_source(RCC_HSE);
rcc_osc_on(RCC_PLL);
rcc_wait_for_osc_ready(RCC_PLL);
rcc_set_sysclk_source(RCC_PLL);
rcc_set_hpre(RCC_CFGR_HPRE_NODIV);
rcc_set_ppre(RCC_CFGR_PPRE_NODIV);
rcc_apb1_frequency = 48000000UL;
rcc_ahb_frequency = 48000000UL;
rcc_set_usbclk_source(RCC_PLL);
}
void rcc_clock_setup_in_hse_8mhz_out_72mhz(void)
{
/* Enable internal high-speed oscillator. */
rcc_osc_on(RCC_HSI);
rcc_wait_for_osc_ready(RCC_HSI);
/* Select HSI as SYSCLK source. */
rcc_set_sysclk_source(RCC_CFGR_SW_SYSCLKSEL_HSICLK);
/* Enable external high-speed oscillator 8MHz. */
rcc_osc_on(RCC_HSE);
rcc_wait_for_osc_ready(RCC_HSE);
rcc_set_sysclk_source(RCC_CFGR_SW_SYSCLKSEL_HSECLK);
/*
* Set prescalers for AHB, ADC, ABP1, ABP2.
* Do this before touching the PLL (TODO: why?).
*/
rcc_set_hpre(RCC_CFGR_HPRE_SYSCLK_NODIV); /* Set. 72MHz Max. 72MHz */
rcc_set_adcpre(RCC_CFGR_ADCPRE_PCLK2_DIV8); /* Set. 9MHz Max. 14MHz */
rcc_set_ppre1(RCC_CFGR_PPRE1_HCLK_DIV2); /* Set. 36MHz Max. 36MHz */
rcc_set_ppre2(RCC_CFGR_PPRE2_HCLK_NODIV); /* Set. 72MHz Max. 72MHz */
/*
* Sysclk runs with 72MHz -> 2 waitstates.
* 0WS from 0-24MHz
* 1WS from 24-48MHz
* 2WS from 48-72MHz
*/
flash_set_ws(FLASH_ACR_LATENCY_2WS);
/*
* Set the PLL multiplication factor to 9.
* 8MHz (external) * 9 (multiplier) = 72MHz
*/
rcc_set_pll_multiplication_factor(RCC_CFGR_PLLMUL_PLL_CLK_MUL9);
/* Select HSE as PLL source. */
rcc_set_pll_source(RCC_CFGR_PLLSRC_HSE_CLK);
/*
* External frequency undivided before entering PLL
* (only valid/needed for HSE).
*/
rcc_set_pllxtpre(RCC_CFGR_PLLXTPRE_HSE_CLK);
/* Enable PLL oscillator and wait for it to stabilize. */
rcc_osc_on(RCC_PLL);
rcc_wait_for_osc_ready(RCC_PLL);
/* Select PLL as SYSCLK source. */
rcc_set_sysclk_source(RCC_CFGR_SW_SYSCLKSEL_PLLCLK);
/* Set the peripheral clock frequencies used */
rcc_ahb_frequency = 72000000;
rcc_apb1_frequency = 36000000;
rcc_apb2_frequency = 72000000;
}
static void rcc_clock_setup_in_hse_12mhz_out_120mhz(void) {
/* Enable internal high-speed oscillator. */
rcc_osc_on(RCC_HSI);
rcc_wait_for_osc_ready(RCC_HSI);
/* Select HSI as SYSCLK source. */
rcc_set_sysclk_source(RCC_CFGR_SW_SYSCLKSEL_HSICLK);
/* Enable external high-speed oscillator 12MHz. */
rcc_osc_on(RCC_HSE);
rcc_wait_for_osc_ready(RCC_HSE);
rcc_set_sysclk_source(RCC_CFGR_SW_SYSCLKSEL_HSECLK);
/*
* Set prescalers for AHB, ADC, ABP1, ABP2.
* Do this before touching the PLL
*/
rcc_set_hpre(RCC_CFGR_HPRE_SYSCLK_NODIV); /* Set. 120MHz Max. 108MHz */
RCC_CFGR = (RCC_CFGR & ~RCC_CFGR_ADCPRE) | RCC_GCFGR_ADCPS_DIV12; /* ADC Set. 10MHz Max. 14MHz */
rcc_set_ppre1(RCC_CFGR_PPRE1_HCLK_DIV2); /* Set. 60MHz Max. 54MHz */
rcc_set_ppre2(RCC_CFGR_PPRE2_HCLK_NODIV); /* Set. 120MHz Max. 108MHz */
RCC_CFGR |= RCC_GCFGR_USBPS_Div2_5; /* USB Set. 48MHz Max. 48MHz */
/* GD32 has 0-wait-state flash, do not touch anything! */
/*
* Set the PLL multiplication factor to 10.
* 12MHz (external) * 10 (multiplier) = 120MHz
*/
rcc_set_pll_multiplication_factor(RCC_CFGR_PLLMUL_PLL_CLK_MUL10);
/* Select HSE as PLL source. */
rcc_set_pll_source(RCC_CFGR_PLLSRC_HSE_CLK);
/*
* External frequency undivided before entering PLL
* (only valid/needed for HSE).
*/
rcc_set_pllxtpre(RCC_CFGR_PLLXTPRE_HSE_CLK);
/* Enable PLL oscillator and wait for it to stabilize. */
rcc_osc_on(RCC_PLL);
rcc_wait_for_osc_ready(RCC_PLL);
/* Select PLL as SYSCLK source. */
rcc_set_sysclk_source(RCC_CFGR_SW_SYSCLKSEL_PLLCLK);
/* Set the peripheral clock frequencies used */
rcc_ahb_frequency = 120000000;
rcc_apb1_frequency = 60000000;
rcc_apb2_frequency = 120000000;
}
void rcc_clock_setup_in_hse_25mhz_out_72mhz(void)
{
/* Enable external high-speed oscillator 25MHz. */
rcc_osc_on(RCC_HSE);
rcc_wait_for_osc_ready(RCC_HSE);
rcc_set_sysclk_source(RCC_CFGR_SW_SYSCLKSEL_HSECLK);
/*
* Sysclk runs with 72MHz -> 2 waitstates.
* 0WS from 0-24MHz
* 1WS from 24-48MHz
* 2WS from 48-72MHz
*/
flash_set_ws(FLASH_ACR_LATENCY_2WS);
/*
* Set prescalers for AHB, ADC, ABP1, ABP2.
* Do this before touching the PLL (TODO: why?).
*/
rcc_set_hpre(RCC_CFGR_HPRE_SYSCLK_NODIV); /* Set. 72MHz Max. 72MHz */
rcc_set_adcpre(RCC_CFGR_ADCPRE_PCLK2_DIV6); /* Set. 12MHz Max. 14MHz */
rcc_set_ppre1(RCC_CFGR_PPRE1_HCLK_DIV2); /* Set. 36MHz Max. 36MHz */
rcc_set_ppre2(RCC_CFGR_PPRE2_HCLK_NODIV); /* Set. 72MHz Max. 72MHz */
/* Set pll2 prediv and multiplier */
rcc_set_prediv2(RCC_CFGR2_PREDIV2_DIV5);
rcc_set_pll2_multiplication_factor(RCC_CFGR2_PLL2MUL_PLL2_CLK_MUL8);
/* Enable PLL2 oscillator and wait for it to stabilize */
rcc_osc_on(RCC_PLL2);
rcc_wait_for_osc_ready(RCC_PLL2);
/* Set pll1 prediv/multiplier, prediv1 src, and usb predivider */
rcc_set_pllxtpre(RCC_CFGR_PLLXTPRE_HSE_CLK);
rcc_set_prediv1_source(RCC_CFGR2_PREDIV1SRC_PLL2_CLK);
rcc_set_prediv1(RCC_CFGR2_PREDIV_DIV5);
rcc_set_pll_multiplication_factor(RCC_CFGR_PLLMUL_PLL_CLK_MUL9);
rcc_set_pll_source(RCC_CFGR_PLLSRC_PREDIV1_CLK);
rcc_set_usbpre(RCC_CFGR_USBPRE_PLL_VCO_CLK_DIV3);
/* enable PLL1 and wait for it to stabilize */
rcc_osc_on(RCC_PLL);
rcc_wait_for_osc_ready(RCC_PLL);
/* Select PLL as SYSCLK source. */
rcc_set_sysclk_source(RCC_CFGR_SW_SYSCLKSEL_PLLCLK);
/* Set the peripheral clock frequencies used */
rcc_ahb_frequency = 72000000;
rcc_apb1_frequency = 36000000;
rcc_apb2_frequency = 72000000;
}
void clocksource_hse_in_8_out_48(void) {
// see
// https://www.mikrocontroller.net/attachment/322047/Clock_Control.png
// or RM00091 p. 98
// enable internal high-speed oscillator
rcc_osc_on(RCC_HSI);
rcc_wait_for_osc_ready(RCC_HSI);
// Select HSI as SYSCLK source.
rcc_set_sysclk_source(RCC_CFGR_SW_HSI);
// Enable external high-speed oscillator 8MHz
rcc_osc_on(RCC_HSE);
rcc_wait_for_osc_ready(RCC_HSE);
rcc_set_sysclk_source(RCC_CFGR_SW_HSE);
// set prescalers for AHB, ADC, ABP1, ABP2.
// Do this before touching the PLL
rcc_set_hpre(RCC_CFGR_HPRE_NODIV); // 48Mhz (max 72)
rcc_set_ppre(RCC_CFGR_PPRE_DIV2); // 24Mhz (max 36)
// sysclk runs with 48MHz -> 1 waitstates.
// * 0WS from 0-24MHz
// * 1WS from 24-48MHz
// * 2WS from 48-72MHz
flash_set_ws(FLASH_ACR_LATENCY_1WS);
// set the PLL multiplication factor to 6
// pll source is hse
RCC_CFGR |= RCC_CFGR_PLLSRC;
// pll prediv = 1
rcc_set_prediv(RCC_CFGR2_PREDIV_NODIV);
// 8MHz (external) * 6 (multiplier) = 48MHz
rcc_set_pll_multiplication_factor(RCC_CFGR_PLLMUL_MUL6);
// enable PLL oscillator and wait for it to stabilize.
rcc_osc_on(RCC_PLL);
rcc_wait_for_osc_ready(RCC_PLL);
// select PLL as SYSCLK source.
rcc_set_sysclk_source(RCC_PLL);
// set the peripheral clock frequencies used */
rcc_ahb_frequency = 48000000;
rcc_apb1_frequency = 24000000;
// When PPRE is set to something != NODIV
// TIM input clock is apb clkspeed*2 (see RM00091 p98)
rcc_timer_frequency = 2*rcc_apb1_frequency;
}
int main(void)
{
/* Enable HSE */
rcc_osc_on(RCC_HSE);
rcc_wait_for_osc_ready(RCC_HSE);
/* setup PLL */
// 8Mhz *8/2 -> 32MHz
rcc_set_pll_source(RCC_HSE);
rcc_set_pll_multiplier(RCC_CFGR_PLLMUL_MUL8);
rcc_set_pll_divider(RCC_CFGR_PLLDIV_DIV2);
rcc_osc_on(RCC_PLL);
rcc_wait_for_osc_ready(RCC_PLL);
/* switch to PLL */
rcc_set_sysclk_source(RCC_PLL);
/* setup AHB/APBx */
rcc_set_hpre(RCC_CFGR_HPRE_NODIV);
rcc_set_ppre1(RCC_CFGR_PPRE1_NODIV);
rcc_set_ppre2(RCC_CFGR_PPRE2_NODIV);
gpio_setup();
systick_setup(2);
/* init switch */
gpio_mode_setup(GPIOA, GPIO_MODE_INPUT, GPIO_PUPD_PULLUP, GPIO12);
gpio_mode_setup(GPIOA, GPIO_MODE_OUTPUT, GPIO_PUPD_NONE, GPIO11);
gpio_clear(GPIOA, GPIO11);
/* get value */
gpio_get(GPIOA, GPIO12);
while (1) {
/*
delay();
gpio_toggle(LED_GREEN_PORT, LED_GREEN_PIN);
delay_short();
gpio_toggle(LED_GREEN_PORT, LED_GREEN_PIN);
delay_short();
gpio_toggle(LED_GREEN_PORT, LED_GREEN_PIN);
delay_short();
gpio_toggle(LED_GREEN_PORT, LED_GREEN_PIN);
delay_short();
*/
}
return 0;
}
void rcc_clock_setup_in_hsi_out_48mhz(void)
{
/* Enable internal high-speed oscillator. */
rcc_osc_on(RCC_HSI);
rcc_wait_for_osc_ready(RCC_HSI);
/* Select HSI as SYSCLK source. */
rcc_set_sysclk_source(RCC_CFGR_SW_SYSCLKSEL_HSICLK);
/*
* Set prescalers for AHB, ADC, ABP1, ABP2.
* Do this before touching the PLL (TODO: why?).
*/
rcc_set_hpre(RCC_CFGR_HPRE_SYSCLK_NODIV); /*Set.48MHz Max.72MHz */
rcc_set_adcpre(RCC_CFGR_ADCPRE_PCLK2_DIV8); /*Set. 6MHz Max.14MHz */
rcc_set_ppre1(RCC_CFGR_PPRE1_HCLK_DIV2); /*Set.24MHz Max.36MHz */
rcc_set_ppre2(RCC_CFGR_PPRE2_HCLK_NODIV); /*Set.48MHz Max.72MHz */
rcc_set_usbpre(RCC_CFGR_USBPRE_PLL_CLK_NODIV); /*Set.48MHz Max.48MHz */
/*
* Sysclk runs with 48MHz -> 1 waitstates.
* 0WS from 0-24MHz
* 1WS from 24-48MHz
* 2WS from 48-72MHz
*/
flash_set_ws(FLASH_ACR_LATENCY_1WS);
/*
* Set the PLL multiplication factor to 12.
* 8MHz (internal) * 12 (multiplier) / 2 (PLLSRC_HSI_CLK_DIV2) = 48MHz
*/
rcc_set_pll_multiplication_factor(RCC_CFGR_PLLMUL_PLL_CLK_MUL12);
/* Select HSI/2 as PLL source. */
rcc_set_pll_source(RCC_CFGR_PLLSRC_HSI_CLK_DIV2);
/* Enable PLL oscillator and wait for it to stabilize. */
rcc_osc_on(RCC_PLL);
rcc_wait_for_osc_ready(RCC_PLL);
/* Select PLL as SYSCLK source. */
rcc_set_sysclk_source(RCC_CFGR_SW_SYSCLKSEL_PLLCLK);
/* Set the peripheral clock frequencies used */
rcc_ahb_frequency = 48000000;
rcc_apb1_frequency = 24000000;
rcc_apb2_frequency = 48000000;
}
void rcc_clock_setup_hsi16(const struct rcc_clock_scale *clock)
{
/* Enable internal high-speed oscillator. */
rcc_osc_on(RCC_HSI16);
rcc_wait_for_osc_ready(RCC_HSI16);
/* Select HSI as SYSCLK source. */
rcc_set_sysclk_source(RCC_CFGR_SW_HSI16);
/* Enable/disable high performance mode */
pwr_set_vos_range(clock->voltage_scale);
/*
* Set prescalers for AHB, ADC, ABP1, ABP2.
* Do this before touching the PLL (TODO: why?).
*/
rcc_set_hpre(clock->hpre);
rcc_set_ppre1(clock->ppre1);
rcc_set_ppre2(clock->ppre2);
/* Configure flash settings. */
flash_set_ws(clock->flash_config);
/* Set the peripheral clock frequencies used. */
rcc_apb1_frequency = clock->apb1_frequency;
rcc_apb2_frequency = clock->apb2_frequency;
rcc_set_msi_range(clock->msi_range);
}
void rcc_clock_setup_hsi(const clock_scale_t *clock)
{
/* Enable internal high-speed oscillator. */
rcc_osc_on(HSI);
rcc_wait_for_osc_ready(HSI);
/* Select HSI as SYSCLK source. */
rcc_set_sysclk_source(RCC_CFGR_SW_SYSCLKSEL_HSICLK);
/*
* Set prescalers for AHB, ADC, ABP1, ABP2.
* Do this before touching the PLL (TODO: why?).
*/
rcc_set_hpre(clock->hpre);
rcc_set_ppre1(clock->ppre1);
rcc_set_ppre2(clock->ppre2);
rcc_peripheral_enable_clock(&RCC_APB1ENR, RCC_APB1ENR_PWREN);
pwr_set_vos_scale(clock->voltage_scale);
/* I guess this should be in the settings? */
flash_64bit_enable();
flash_prefetch_enable();
/* Configure flash settings. */
flash_set_ws(clock->flash_config);
/* Set the peripheral clock frequencies used. */
rcc_apb1_frequency = clock->apb1_frequency;
rcc_apb2_frequency = clock->apb2_frequency;
}
void rcc_clock_setup_hsi_3v3(const clock_scale_t *clock)
{
/* Enable internal high-speed oscillator. */
rcc_osc_on(HSI);
rcc_wait_for_osc_ready(HSI);
/* Select HSI as SYSCLK source. */
rcc_set_sysclk_source(RCC_CFGR_SW_HSI);
// /* Enable/disable high performance mode */
// if (!clock->power_save) {
// pwr_set_vos_scale(SCALE1);
// } else {
// pwr_set_vos_scale(SCALE2);
// }
/*
* Set prescalers for AHB, ADC, ABP1, ABP2.
* Do this before touching the PLL (TODO: why?).
*/
rcc_set_hpre(clock->hpre);
rcc_set_ppre1(clock->ppre1);
rcc_set_ppre2(clock->ppre2);
rcc_set_main_pll_hsi(clock->pllm, clock->plln,
clock->pllp, clock->pllq);
/* Enable PLL oscillator and wait for it to stabilize. */
rcc_osc_on(PLL);
rcc_wait_for_osc_ready(PLL);
/* Configure flash settings. */
flash_set_ws(clock->flash_config);
/* Select PLL as SYSCLK source. */
rcc_set_sysclk_source(RCC_CFGR_SW_PLL);
/* Wait for PLL clock to be selected. */
rcc_wait_for_sysclk_status(PLL);
/* Set the peripheral clock frequencies used. */
rcc_apb1_frequency = clock->apb1_frequency;
rcc_apb2_frequency = clock->apb2_frequency;
/* Disable internal high-speed oscillator. */
//rcc_osc_off(HSI);
}
void PWR_Shutdown()
{
printf("Shutdown\n");
BACKLIGHT_Brightness(0);
rcc_set_sysclk_source(RCC_CFGR_SW_SYSCLKSEL_HSICLK);
rcc_wait_for_osc_ready(HSI);
while(1) ;
}
/* Set the clock to max speed. */
static void clock_setup(void)
{
#if defined(STM32F0)
rcc_clock_setup_in_hsi_out_48mhz();
#elif defined(STM32L0)
/* After a reset, the system uses [email protected]. */
/* end result: 32MHz PLLVCO from HSI16,
* no system/periph clock divide.
*/
/* increase the latency to 1 wait state (we'll be speeding up) */
flash_set_ws(1);
/* turn on HSI16 */
rcc_osc_on(RCC_HSI16);
rcc_wait_for_osc_ready(RCC_HSI16);
/* run AHB, APB1, APB2 at full speed */
rcc_set_hpre(RCC_CFGR_HPRE_NODIV);
rcc_set_ppre1(RCC_CFGR_PPRE1_NODIV);
rcc_set_ppre2(RCC_CFGR_PPRE2_NODIV);
/* turn off PLL and wait for it to fully stop */
rcc_osc_off(RCC_PLL);
while (RCC_CR & RCC_CR_PLLRDY);
/* set PLL source to HSI16 */
RCC_CFGR &= ~(1<<16); // RCC_CFGR_PLLSRC
/* set up PLL */
rcc_set_pll_multiplier(RCC_CFGR_PLLMUL_MUL4);
rcc_set_pll_divider(RCC_CFGR_PLLDIV_DIV2);
/* turn on and switch to PLL */
rcc_osc_on(RCC_PLL);
rcc_wait_for_osc_ready(RCC_PLL);
rcc_set_sysclk_source(RCC_PLL);
rcc_ahb_frequency = 32000000;
rcc_apb1_frequency = 32000000;
rcc_apb2_frequency = 32000000;
#else
#error "Implement a clock setup."
#endif
}
void rcc_clock_setup_pll(const struct rcc_clock_scale *clock)
{
/* Turn on the appropriate source for the PLL */
if (clock->pll_source == RCC_CFGR_PLLSRC_HSE_CLK) {
rcc_osc_on(RCC_HSE);
rcc_wait_for_osc_ready(RCC_HSE);
} else {
rcc_osc_on(RCC_HSI);
rcc_wait_for_osc_ready(RCC_HSI);
}
/*
* Set prescalers for AHB, ADC, ABP1, ABP2.
* Do this before touching the PLL (TODO: why?).
*/
rcc_set_hpre(clock->hpre);
rcc_set_ppre1(clock->ppre1);
rcc_set_ppre2(clock->ppre2);
rcc_periph_clock_enable(RCC_PWR);
pwr_set_vos_scale(clock->voltage_scale);
/* I guess this should be in the settings? */
flash_64bit_enable();
flash_prefetch_enable();
/* Configure flash settings. */
flash_set_ws(clock->flash_config);
rcc_set_pll_configuration(clock->pll_source, clock->pll_mul,
clock->pll_div);
/* Enable PLL oscillator and wait for it to stabilize. */
rcc_osc_on(RCC_PLL);
rcc_wait_for_osc_ready(RCC_PLL);
/* Select PLL as SYSCLK source. */
rcc_set_sysclk_source(RCC_CFGR_SW_SYSCLKSEL_PLLCLK);
/* Set the peripheral clock frequencies used. */
rcc_ahb_frequency = clock->ahb_frequency;
rcc_apb1_frequency = clock->apb1_frequency;
rcc_apb2_frequency = clock->apb2_frequency;
}
/*
* 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(RCC_CFGR_SW_SYSCLKSEL_HSICLK);
/*
* Set prescalers for AHB, ADC, ABP1, ABP2.
* Do this before touching the PLL (TODO: why?).
*/
rcc_set_hpre(RCC_CFGR_HPRE_SYSCLK_NODIV); /* Max. 72MHz */
rcc_set_adcpre(RCC_CFGR_ADCPRE_PCLK2_DIV8); /* Max. 14MHz */
rcc_set_ppre1(RCC_CFGR_PPRE1_HCLK_DIV2); /* Max. 36MHz */
rcc_set_ppre2(RCC_CFGR_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(RCC_CFGR_PLLMUL_PLL_CLK_MUL16);
/* Select HSI/2 as PLL source. */
rcc_set_pll_source(RCC_CFGR_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(RCC_CFGR_SW_SYSCLKSEL_PLLCLK);
}
void clock_init(void) {
/* Enable HSE */
rcc_osc_on(RCC_HSE);
rcc_wait_for_osc_ready(RCC_HSE);
/* setup PLL */
// 8Mhz *8/2 -> 32MHz
rcc_set_pll_source(RCC_HSE);
rcc_set_pll_multiplier(RCC_CFGR_PLLMUL_MUL8);
rcc_set_pll_divider(RCC_CFGR_PLLDIV_DIV2);
rcc_osc_on(RCC_PLL);
rcc_wait_for_osc_ready(RCC_PLL);
/* switch to PLL */
rcc_set_sysclk_source(RCC_PLL);
/* setup AHB/APBx */
rcc_set_hpre(RCC_CFGR_HPRE_NODIV);
rcc_set_ppre1(RCC_CFGR_PPRE1_NODIV);
rcc_set_ppre2(RCC_CFGR_PPRE2_NODIV);
}
/**
* Setup clocks to run from PLL.
* The arguments provide the pll source, multipliers, dividers, all that's
* needed to establish a system clock.
* @param clock clock information structure
*/
void rcc_clock_setup_pll(const struct rcc_clock_scale *clock)
{
if (clock->pllsrc == RCC_CFGR_PLLSRC_HSE_PREDIV) {
rcc_osc_on(RCC_HSE);
rcc_wait_for_osc_ready(RCC_HSE);
} else {
rcc_osc_on(RCC_HSI);
rcc_wait_for_osc_ready(RCC_HSI);
}
rcc_osc_off(RCC_PLL);
rcc_usb_prescale_1_5();
if (clock->usbdiv1) {
rcc_usb_prescale_1();
}
rcc_wait_for_osc_not_ready(RCC_PLL);
rcc_set_pll_source(clock->pllsrc);
rcc_set_pll_multiplier(clock->pllmul);
rcc_set_prediv(clock->plldiv);
/* Enable PLL oscillator and wait for it to stabilize. */
rcc_osc_on(RCC_PLL);
rcc_wait_for_osc_ready(RCC_PLL);
/* Configure flash settings. */
flash_prefetch_enable();
flash_set_ws(clock->flash_waitstates);
rcc_set_hpre(clock->hpre);
rcc_set_ppre2(clock->ppre2);
rcc_set_ppre1(clock->ppre1);
/* Select PLL as SYSCLK source. */
rcc_set_sysclk_source(RCC_CFGR_SW_PLL);
/* Wait for PLL clock to be selected. */
rcc_wait_for_sysclk_status(RCC_PLL);
/* Set the peripheral clock frequencies used. */
rcc_ahb_frequency = clock->ahb_frequency;
rcc_apb1_frequency = clock->apb1_frequency;
rcc_apb2_frequency = clock->apb2_frequency;
}
void rcc_clock_setup_in_hsi_out_8mhz(void)
{
rcc_osc_on(HSI);
rcc_wait_for_osc_ready(HSI);
rcc_set_sysclk_source(HSI);
rcc_set_hpre(RCC_CFGR_HPRE_NODIV);
rcc_set_ppre(RCC_CFGR_PPRE_NODIV);
flash_set_ws(FLASH_ACR_LATENCY_000_024MHZ);
rcc_ppre_frequency = 8000000;
rcc_core_frequency = 8000000;
}
void rcc_clock_setup_in_hsi_out_40mhz(void)
{
rcc_osc_on(RCC_HSI);
rcc_wait_for_osc_ready(RCC_HSI);
rcc_set_sysclk_source(RCC_HSI);
rcc_set_hpre(RCC_CFGR_HPRE_NODIV);
rcc_set_ppre(RCC_CFGR_PPRE_NODIV);
flash_set_ws(FLASH_ACR_LATENCY_024_048MHZ);
/* 8MHz * 10 / 2 = 40MHz */
rcc_set_pll_multiplication_factor(RCC_CFGR_PLLMUL_MUL10);
RCC_CFGR &= ~RCC_CFGR_PLLSRC;
rcc_osc_on(RCC_PLL);
rcc_wait_for_osc_ready(RCC_PLL);
rcc_set_sysclk_source(RCC_PLL);
rcc_apb1_frequency = 40000000;
rcc_ahb_frequency = 40000000;
}
/**
* Set System Clock PLL at 48MHz from HSI
*/
void rcc_clock_setup_in_hsi_out_48mhz(void)
{
rcc_osc_on(RCC_HSI);
rcc_wait_for_osc_ready(RCC_HSI);
rcc_set_sysclk_source(RCC_HSI);
rcc_set_hpre(RCC_CFGR_HPRE_NODIV);
rcc_set_ppre(RCC_CFGR_PPRE_NODIV);
flash_prefetch_enable();
flash_set_ws(FLASH_ACR_LATENCY_024_048MHZ);
/* 8MHz * 12 / 2 = 48MHz */
rcc_set_pll_multiplication_factor(RCC_CFGR_PLLMUL_MUL12);
rcc_set_pll_source(RCC_CFGR_PLLSRC_HSI_CLK_DIV2);
rcc_osc_on(RCC_PLL);
rcc_wait_for_osc_ready(RCC_PLL);
rcc_set_sysclk_source(RCC_PLL);
rcc_apb1_frequency = 48000000;
rcc_ahb_frequency = 48000000;
}
void rcc_clock_setup_in_hsi_out_16mhz(void)
{
rcc_osc_on(HSI);
rcc_wait_for_osc_ready(HSI);
rcc_set_sysclk_source(HSI);
rcc_set_hpre(RCC_CFGR_HPRE_NODIV);
rcc_set_ppre(RCC_CFGR_PPRE_NODIV);
flash_set_ws(FLASH_ACR_LATENCY_000_024MHZ);
/* 8MHz * 4 / 2 = 16MHz */
rcc_set_pll_multiplication_factor(RCC_CFGR_PLLMUL_MUL4);
RCC_CFGR &= ~RCC_CFGR_PLLSRC;
rcc_osc_on(PLL);
rcc_wait_for_osc_ready(PLL);
rcc_set_sysclk_source(PLL);
rcc_apb1_frequency = 16000000;
rcc_ahb_frequency = 16000000;
}
void rcc_clock_setup_in_hsi_out_48mhz(void)
{
rcc_osc_on(HSI);
rcc_wait_for_osc_ready(HSI);
rcc_set_sysclk_source(HSI);
rcc_set_hpre(RCC_CFGR_HPRE_NODIV);
rcc_set_ppre(RCC_CFGR_PPRE_NODIV);
flash_set_ws(FLASH_ACR_LATENCY_024_048MHZ);
/* 8MHz * 12 / 2 = 24MHz */
rcc_set_pll_multiplication_factor(RCC_CFGR_PLLMUL_MUL16);
RCC_CFGR &= RCC_CFGR_PLLSRC;
rcc_osc_on(PLL);
rcc_wait_for_osc_ready(PLL);
rcc_set_sysclk_source(PLL);
rcc_ppre_frequency = 48000000;
rcc_core_frequency = 48000000;
}
/**
* Set up sysclock with PLL from HSI16
* @param clock full struct with desired parameters
*/
void rcc_clock_setup_pll(const struct rcc_clock_scale *clock)
{
/* Turn on the appropriate source for the PLL */
if (clock->pll_source == RCC_CFGR_PLLSRC_HSE_CLK) {
rcc_osc_on(RCC_HSE);
rcc_wait_for_osc_ready(RCC_HSE);
} else {
rcc_osc_on(RCC_HSI16);
rcc_wait_for_osc_ready(RCC_HSI16);
}
rcc_set_hpre(clock->hpre);
rcc_set_ppre1(clock->ppre1);
rcc_set_ppre2(clock->ppre2);
rcc_periph_clock_enable(RCC_PWR);
pwr_set_vos_scale(clock->voltage_scale);
rcc_osc_off(RCC_PLL);
while (rcc_is_osc_ready(RCC_PLL));
flash_prefetch_enable();
flash_set_ws(clock->flash_waitstates);
/* Set up the PLL */
rcc_set_pll_multiplier(clock->pll_mul);
rcc_set_pll_divider(clock->pll_div);
rcc_osc_on(RCC_PLL);
rcc_wait_for_osc_ready(RCC_PLL);
rcc_set_sysclk_source(RCC_PLL);
/* Set the peripheral clock frequencies used. */
rcc_ahb_frequency = clock->ahb_frequency;
rcc_apb1_frequency = clock->apb1_frequency;
rcc_apb2_frequency = clock->apb2_frequency;
}
void rcc_clock_setup_in_hsi48_out_48mhz(void)
{
rcc_osc_on(RCC_HSI48);
rcc_wait_for_osc_ready(RCC_HSI48);
rcc_set_hpre(RCC_CFGR_HPRE_NODIV);
rcc_set_ppre(RCC_CFGR_PPRE_NODIV);
flash_set_ws(FLASH_ACR_LATENCY_024_048MHZ);
rcc_set_sysclk_source(RCC_HSI48);
rcc_apb1_frequency = 48000000;
rcc_ahb_frequency = 48000000;
}
static int setup_rtc(void)
{
/* turn on power block to enable unlocking */
rcc_periph_clock_enable(RCC_PWR);
pwr_disable_backup_domain_write_protect();
/* reset rtc */
RCC_CSR |= RCC_CSR_RTCRST;
RCC_CSR &= ~RCC_CSR_RTCRST;
/* We want to use the LSE fitted on the discovery board */
rcc_osc_on(RCC_LSE);
rcc_wait_for_osc_ready(RCC_LSE);
/* Select the LSE as rtc clock */
rcc_rtc_select_clock(RCC_CSR_RTCSEL_LSE);
/* ?! Stdperiph examples don't turn this on until _afterwards_ which
* simply doesn't work. It must be on at least to be able to
* configure it */
RCC_CSR |= RCC_CSR_RTCEN;
rtc_unlock();
/* enter init mode */
RTC_ISR |= RTC_ISR_INIT;
while ((RTC_ISR & RTC_ISR_INITF) == 0);
/* set synch prescaler, using defaults for 1Hz out */
uint32_t sync = 255;
uint32_t async = 127;
rtc_set_prescaler(sync, async);
/* load time and date here if desired, and hour format */
/* exit init mode */
RTC_ISR &= ~(RTC_ISR_INIT);
/* and write protect again */
rtc_lock();
/* and finally enable the clock */
RCC_CSR |= RCC_CSR_RTCEN;
/* And wait for synchro.. */
rtc_wait_for_synchro();
return 0;
}
/*--------------------------------------------------------------------*/
void hardware_setup(void)
{
/* Setup the clock to 72MHz from the 8MHz external crystal */
rcc_clock_setup_in_hse_8mhz_out_72mhz();
rcc_periph_clock_enable(RCC_GPIOB);
gpio_set_mode(GPIOB, GPIO_MODE_OUTPUT_2_MHZ,
GPIO_CNF_OUTPUT_PUSHPULL, GPIO8 | GPIO9 | GPIO10 | GPIO11 |
GPIO12 | GPIO13 | GPIO14 | GPIO15);
rcc_osc_on(LSI);
rcc_wait_for_osc_ready(LSI);
iwdg_set_period_ms(5000);
iwdg_start();
}
int main(void)
{
int32_t i;
rcc_periph_clock_enable(RCC_GPIOA);
gpio_set_mode(GPIOA, GPIO_MODE_OUTPUT_2_MHZ, GPIO_CNF_OUTPUT_PUSHPULL, GPIO5);
flash_set_ws(FLASH_ACR_LATENCY_2WS);
rcc_set_adcpre(RCC_CFGR_ADCPRE_PCLK2_DIV4); /* 14MHz */
rcc_set_hpre(RCC_CFGR_HPRE_SYSCLK_NODIV); /* 56MHz */
rcc_set_ppre1(RCC_CFGR_PPRE1_HCLK_DIV2); /* 28MHz */
rcc_set_ppre2(RCC_CFGR_PPRE2_HCLK_NODIV); /* 56MHz */
rcc_set_pll_multiplication_factor(RCC_CFGR_PLLMUL_PLL_CLK_MUL14); /* 8MHz/2 x14 = 56MHz */
rcc_set_pll_source(RCC_CFGR_PLLSRC_HSI_CLK_DIV2);
rcc_osc_on(PLL);
rcc_wait_for_osc_ready(PLL);
rcc_set_sysclk_source(RCC_CFGR_SW_SYSCLKSEL_PLLCLK);
rcc_periph_clock_enable(RCC_USART2);
gpio_set_mode(GPIOA, GPIO_MODE_OUTPUT_50_MHZ, GPIO_CNF_OUTPUT_ALTFN_PUSHPULL, GPIO_USART2_TX);
gpio_set_mode(GPIOA, GPIO_MODE_INPUT, GPIO_CNF_INPUT_FLOAT, GPIO_USART2_RX);
uint32_t baud = 57600;
uint32_t clock = 28000000;
USART2_BRR = ((2 * clock) + baud) / (2 * baud);
usart_set_databits(USART2, 8);
usart_set_stopbits(USART2, USART_STOPBITS_1);
usart_set_mode(USART2, USART_MODE_TX_RX);
usart_set_parity(USART2, USART_PARITY_NONE);
usart_set_flow_control(USART2, USART_FLOWCONTROL_NONE);
usart_enable(USART2);
usart_puts(USART2, "ready to receive.\r\n");
gpio_set(GPIOA, GPIO5);
while(1)
{
uint16_t c;
c = usart_recv_blocking(USART2);
usart_send_blocking(USART2, toupper(c));
gpio_toggle(GPIOA, GPIO5);
}
}
/**
* Switch sysclock to HSI with the given parameters.
* This should be usable from any point in time, but only if you have used
* library functions to manage clocks. It relies on the global
* @ref rcc_ahb_frequency to ensure that it reliably scales voltage up or down
* as appropriate.
* @param clock full struct with desired parameters
*/
void rcc_clock_setup_hsi(const struct rcc_clock_scale *clock)
{
/* Enable internal high-speed oscillator. */
rcc_osc_on(RCC_HSI);
rcc_periph_clock_enable(RCC_PWR);
/* I guess this should be in the settings? */
flash_64bit_enable();
flash_prefetch_enable();
/* Don't try and go to fast for a voltage range! */
if (clock->ahb_frequency > rcc_ahb_frequency) {
/* Going up, power up first */
pwr_set_vos_scale(clock->voltage_scale);
rcc_set_hpre(clock->hpre);
rcc_set_ppre1(clock->ppre1);
rcc_set_ppre2(clock->ppre2);
flash_set_ws(clock->flash_config);
} else {
/* going down, slow down before cutting power */
rcc_set_hpre(clock->hpre);
rcc_set_ppre1(clock->ppre1);
rcc_set_ppre2(clock->ppre2);
flash_set_ws(clock->flash_config);
pwr_set_vos_scale(clock->voltage_scale);
}
rcc_wait_for_osc_ready(RCC_HSI);
while (PWR_CSR & PWR_CSR_VOSF)
;
rcc_set_sysclk_source(RCC_CFGR_SW_SYSCLKSEL_HSICLK);
/* Set the peripheral clock frequencies used. */
rcc_ahb_frequency = clock->ahb_frequency;
rcc_apb1_frequency = clock->apb1_frequency;
rcc_apb2_frequency = clock->apb2_frequency;
}
void rcc_clock_setup_msi(const struct rcc_clock_scale *clock)
{
/* Enable internal multi-speed oscillator. */
uint32_t reg = RCC_ICSCR;
reg &= ~(RCC_ICSCR_MSIRANGE_MASK << RCC_ICSCR_MSIRANGE_SHIFT);
reg |= (clock->msi_range << RCC_ICSCR_MSIRANGE_SHIFT);
RCC_ICSCR = reg;
rcc_osc_on(RCC_MSI);
rcc_wait_for_osc_ready(RCC_MSI);
/* Select MSI as SYSCLK source. */
rcc_set_sysclk_source(RCC_CFGR_SW_SYSCLKSEL_MSICLK);
/*
* Set prescalers for AHB, ADC, ABP1, ABP2.
* Do this before touching the PLL (TODO: why?).
*/
rcc_set_hpre(clock->hpre);
rcc_set_ppre1(clock->ppre1);
rcc_set_ppre2(clock->ppre2);
rcc_peripheral_enable_clock(&RCC_APB1ENR, RCC_APB1ENR_PWREN);
pwr_set_vos_scale(clock->voltage_scale);
/* I guess this should be in the settings? */
flash_64bit_enable();
flash_prefetch_enable();
/* Configure flash settings. */
flash_set_ws(clock->flash_config);
/* Set the peripheral clock frequencies used. */
rcc_apb1_frequency = clock->apb1_frequency;
rcc_apb2_frequency = clock->apb2_frequency;
}
