diff options
Diffstat (limited to 'libmaple/systick.h')
| -rw-r--r-- | libmaple/systick.h | 46 |
1 files changed, 38 insertions, 8 deletions
diff --git a/libmaple/systick.h b/libmaple/systick.h index 33a3cf8..35b4cb9 100644 --- a/libmaple/systick.h +++ b/libmaple/systick.h @@ -31,30 +31,60 @@ #ifndef _SYSTICK_H_ #define _SYSTICK_H_ -#include "libmaple.h" +#include "libmaple_types.h" +#include "util.h" #ifdef __cplusplus extern "C"{ #endif -#define SYSTICK_CSR 0xE000E010 // Control and status register -#define SYSTICK_CNT 0xE000E018 // Current value register +/** SysTick register map type */ +typedef struct systick_reg_map { + __io uint32 CSR; /**< Control and status register */ + __io uint32 RVR; /**< Reload value register */ + __io uint32 CNT; /**< Current value register ("count") */ + __io uint32 CVR; /**< Calibration value register */ +} systick_reg_map; -#define SYSTICK_CSR_COUNTFLAG BIT(16) +/** SysTick register map base pointer */ +#define SYSTICK_BASE ((struct systick_reg_map*)0xE000E010) -/** System elapsed time in milliseconds */ +/* + * Register bit definitions. + */ + +/* Control and status register */ + +#define SYSTICK_CSR_COUNTFLAG BIT(16) +#define SYSTICK_CSR_CLKSOURCE BIT(2) +#define SYSTICK_CSR_CLKSOURCE_EXTERNAL 0 +#define SYSTICK_CSR_CLKSOURCE_CORE BIT(2) +#define SYSTICK_CSR_TICKINT BIT(1) +#define SYSTICK_CSR_TICKINT_PEND BIT(1) +#define SYSTICK_CSR_TICKINT_NO_PEND 0 +#define SYSTICK_CSR_ENABLE BIT(0) +#define SYSTICK_CSR_ENABLE_MULTISHOT BIT(0) +#define SYSTICK_CSR_ENABLE_DISABLED 0 + +/* Calibration value register */ + +#define SYSTICK_CVR_NOREF BIT(31) +#define SYSTICK_CVR_SKEW BIT(30) +#define SYSTICK_CVR_TENMS 0xFFFFFF + +/** System elapsed time, in milliseconds */ extern volatile uint32 systick_timer_millis; void systick_init(uint32 reload_val); void systick_disable(); -void systick_resume(); +void systick_enable(); static inline uint32 systick_get_count(void) { - return __read(SYSTICK_CNT); + return SYSTICK_BASE->CNT; } static inline uint32 systick_check_underflow(void) { - return (__read(SYSTICK_CSR) & SYSTICK_CSR_COUNTFLAG); + return SYSTICK_BASE->CSR & SYSTICK_CSR_COUNTFLAG; } #ifdef __cplusplus |