NXP Semiconductors LPC84x, Руководство пользователя

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UM11029 All information provided in this document is subject to legal disclaimers. © NXP Semiconductors N.V. 2017. All rights reserved.
User manual Rev. 1.0 — 16 June 2017 378 of 515
NXP Semiconductors
UM11029
Chapter 21: LPC84x SCTimer/PWM
Remark:
In this chapter, the term bus error indicates an SCTimer/PWM response that
makes the processor take an exception.
21.6 Register description
The register addresses of the SCTimer/PWM are shown in Table 385 . For most of the
SCTimer/PWM registers, the register function depends on the setting of certain other
register bits:
1. The UNIFY bit in the CONFIG register determines whether the SCTimer/PWM is used
as one 32-bit register (for operation as one 32-bit counter/timer) or as two 16-bit
counter/timers named L and H. The setting of the UNIFY bit is reflected in the register
map:
–
UNIFY = 1: Only one register is used (for operation as one 32-bit counter/timer).
–
UNIFY = 0: Access the L and H registers by a 32-bit read or write operation or can
be read or written to individually (for operation as two 16-bit counter/timers).
Typically, the UNIFY bit is configured by writing to the CONFIG register before any
other registers are accessed.
2. The REGMODEn bits in the REGMODE register determine whether each set of
Match/Capture registers uses the match or capture functionality:
–
REGMODEn = 0: Registers operate as match and reload registers.
–
REGMODEn = 1: Registers operate as capture and capture control registers.
Fig 43. SCTimer/PWM counter and select logic
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Table 385. Register overview: SCTimer/PWM (base address 0x5000 4000)
Name Access Address offset Description Reset value Section
CONFIG R/W 0x000 SCT configuration register 0x0000 7E00 21.6.2
CTRL R/W 0x004 SCT control register 0x0004 0004 21.6.3
CTRL_L R/W 0x004 SCT control register low counter 16-bit 0x0004 0004 21.6.3