OM13008,598 NXP Semiconductors, OM13008,598 Datasheet - Page 272

• Manufacturer Part Number: OM13008,598
• Description: BOARD LPC XPRESSO LPC122X
• Manufacturer: NXP Semiconductors
• Series: LPCXpressor

Specifications of OM13008,598

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 568-6642; OM13008

NXP Semiconductors
UM10441
User manual
15.5.2 System Timer Reload value register
15.5.3 System Timer Current value register
15.5.4 System Timer Calibration value register (SYST_CALIB - 0xE000 E01C)
Table 250. SysTick Timer Control and status register (SYST_CSR - 0xE000 E010) bit
The SYST_RVR register is set to the value that will be loaded into the SysTick timer
whenever it counts down to zero. This register is loaded by software as part of timer
initialization. The SYST_CALIB register may be read and used as the value for
SYST_RVR register if the CPU is running at the frequency intended for use with the
SYST_CALIB value.
Table 251. System Timer Reload value register (SYST_RVR - 0xE000 E014) bit description
The SYST_CVR register returns the current count from the System Tick counter when it is
read by software.
Table 252. System Timer Current value register (SYST_CVR - 0xE000 E018) bit description
The value of the SYST_CALIB register is driven by the value of the SYSTCKCAL register
in the system configuration block (see
Bit
15:3
16
31:17 -
Bit
23:0
31:24
Bit
23:0
31:24
Symbol
-
COUNTFLAG Returns 1 if the SysTick timer counted to 0 since the last read of
Symbol
RELOAD
-
Symbol
CURRENT Reading this register returns the current value of the System Tick
-
description
All information provided in this document is subject to legal disclaimers.
Description
This is the value that is loaded into the System Tick counter when it
counts down to 0.
Reserved, user software should not write ones to reserved bits.
The value read from a reserved bit is not defined.
Description
counter. Writing any value clears the System Tick counter and the
COUNTFLAG bit in STCTRL.
Reserved, user software should not write ones to reserved bits. The
value read from a reserved bit is not defined.
Description
Reserved, user software should not write ones to reserved bits.
The value read from a reserved bit is not defined.
this register.
Reserved, user software should not write ones to reserved bits.
The value read from a reserved bit is not defined.
Rev. 1.1 — 10 March 2011
Chapter 15: LPC122x System Tick (SysTick) timer
Section
4.5.26).
UM10441
© NXP B.V. 2011. All rights reserved.
Reset
value
0
NA
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Reset
value
NA
0
NA
Reset
value
0
NA