Functions

Functions
void	Cy_SysClk_ExtClkSetFrequency (uint32_t freq)
	Sets the signal frequency of the External Clock Source (EXTCLK) into the internal storage to be used in Cy_SysClk_ClkHfGetFrequency. More...
uint32_t	Cy_SysClk_ExtClkGetFrequency (void)
	Returns the frequency of the External Clock Source (EXTCLK) from the internal storage. More...

Detailed Description

Function Documentation

Cy_SysClk_ExtClkSetFrequency()

void Cy_SysClk_ExtClkSetFrequency

(

uint32_t

freq

)

Sets the signal frequency of the External Clock Source (EXTCLK) into the internal storage to be used in Cy_SysClk_ClkHfGetFrequency.

Parameters

freq	The frequency of the External Clock Source. Valid range is 0...48000000 (0...48 MHz). Zero means the external clock signal is not applied.

Function Usage

    /* Scenario: External precision 5MHz clock is needed to source HFCLK. */

    /* Configure the pin P0_6 to be an external clock input */
    Cy_GPIO_Pin_FastInit(GPIO_PRT0, 6UL, CY_GPIO_DM_HIGHZ, 0UL, P0_6_SRSS_EXT_CLK);

    /* Set the EXTCLK frequency to 5MHz */
    Cy_SysClk_ExtClkSetFrequency(5000000UL);
    /* Set the EXTCLK as the source for HFCLK */
    if (CY_SYSCLK_SUCCESS != Cy_SysClk_ClkHfSetSource(CY_SYSCLK_CLKHF_IN_EXTCLK))
    {
        /* Insert error handling */
    }

    /* In case if there is a need to get the EXTCLK frequency */
    uint32_t extClkFrequency = Cy_SysClk_ExtClkGetFrequency();

Cy_SysClk_ExtClkGetFrequency()

uint32_t Cy_SysClk_ExtClkGetFrequency

(

void

)

Returns the frequency of the External Clock Source (EXTCLK) from the internal storage.

Returns

The frequency of the External Clock Source.

Function Usage

    /* Scenario: External precision 5MHz clock is needed to source HFCLK. */

    /* Configure the pin P0_6 to be an external clock input */
    Cy_GPIO_Pin_FastInit(GPIO_PRT0, 6UL, CY_GPIO_DM_HIGHZ, 0UL, P0_6_SRSS_EXT_CLK);

    /* Set the EXTCLK frequency to 5MHz */
    Cy_SysClk_ExtClkSetFrequency(5000000UL);
    /* Set the EXTCLK as the source for HFCLK */
    if (CY_SYSCLK_SUCCESS != Cy_SysClk_ClkHfSetSource(CY_SYSCLK_CLKHF_IN_EXTCLK))
    {
        /* Insert error handling */
    }

    /* In case if there is a need to get the EXTCLK frequency */
    uint32_t extClkFrequency = Cy_SysClk_ExtClkGetFrequency();