Texas Instruments Tiva TM4C123GH6PM, User Manual

Page: 227 / 352

System Tick (SysTick)
20 System Tick (SysTick)
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 227
Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 227
20.1 Introduction
SysTick is a simple timer that is part of the NVIC controller in the Cortex-M4 microprocessor. Its
intended purpose is to provide a periodic interrupt for a RTOS, but it can be used for other simple
timing purposes.
The SysTick interrupt handler does not need to clear the SysTick interrupt source. This will be done
automatically by NVIC when the SysTick interrupt handler is called.
20.2 Functions
Functions
void ROM_SysTickDisable (void)
void ROM_SysTickEnable (void)
void ROM_SysTickIntDisable (void)
void ROM_SysTickIntEnable (void)
uint32_t ROM_SysTickPeriodGet (void)
void ROM_SysTickPeriodSet (uint32_t ui32Period)
uint32_t ROM_SysTickValueGet (void)
20.2.1 Function Documentation
20.2.1.1 ROM_SysTickDisable
Disables the SysTick counter.
Prototype:
void
ROM_SysTickDisable(void)
ROM Location:
ROM_APITABLE
is an array of pointers located at
0x0100.0010
.
ROM_SYSTICKTABLE
is an array of pointers located at
ROM_APITABLE[10]
.
ROM_SysTickDisable
is a function pointer located at
ROM_SYSTICKTABLE[2]
.
Description:
This will stop the SysTick counter. If an interrupt handler has been registered, it will no longer
be called until SysTick is restarted.
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