NXP Semiconductors /LPC43xx /SCT /CTRL

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Interpret as CTRL

31 2827 2423 2019 1615 1211 87 43 0 0 0 0 0 0 0 0 00 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 (DOWN_L)DOWN_L 0 (STOP_L)STOP_L 0 (HALT_L)HALT_L 0 (CLRCTR_L)CLRCTR_L 0 (UP)BIDIR_L 0PRE_L0RESERVED 0 (DOWN_H)DOWN_H 0 (STOP_H)STOP_H 0 (HALT_H)HALT_H 0 (CLRCTR_H)CLRCTR_H 0 (UP)BIDIR_H 0PRE_H0RESERVED

BIDIR_H=UP, BIDIR_L=UP

Description

SCT control register

Fields

DOWN_L

This bit is 1 when the L or unified counter is counting down. Hardware sets this bit when the counter limit is reached and BIDIR is 1. Hardware clears this bit when the counter reaches 0 or when the counter is counting down and a limit condition occurs.

STOP_L

When this bit is 1 and HALT is 0, the L or unified counter does not run but I/O events related to the counter can occur. If such an event matches the mask in the Start register, this bit is cleared and counting resumes.

HALT_L

When this bit is 1, the L or unified counter does not run and no events can occur. A reset sets this bit. When the HALT_L bit is one, the STOP_L bit is cleared. If you want to remove the halt condition and keep the SCT in the stop condition (not running), then you can change the halt and stop condition with one single write to this register. Once set, only software can clear this bit to restore counter operation.

CLRCTR_L

Writing a 1 to this bit clears the L or unified counter. This bit always reads as 0.

BIDIR_L

L or unified counter direction select

0 (UP): Up. The counter counts up to its limit condition, then is cleared to zero.

1 (UPDOWN): Up-down. The counter counts up to its limit, then counts down to a limit condition or to 0.

PRE_L

Specifies the factor by which the SCT clock is prescaled to produce the L or unified counter clock. The counter clock is clocked at the rate of the SCT clock divided by PRE_L+1. Clear the counter (by writing a 1 to the CLRCTR bit) whenever changing the PRE value.

RESERVED

Reserved

DOWN_H

This bit is 1 when the H counter is counting down. Hardware sets this bit when the counter limit is reached and BIDIR is 1. Hardware clears this bit when the counter reaches 0 or when the counter is counting down and a limit condition occurs.

STOP_H

When this bit is 1 and HALT is 0, the H counter does not run but I/O events related to the counter can occur. If such an event matches the mask in the Start register, this bit is cleared and counting resumes.

HALT_H

When this bit is 1, the H counter does not run and no events can occur. A reset sets this bit. When the HALT_H bit is one, the STOP_H bit is cleared. If you want to remove the halt condition and keep the SCT in the stop condition (not running), then you can change the halt and stop condition with one single write to this register. Once set, this bit can only be cleared by software to restore counter operation.

CLRCTR_H

Writing a 1 to this bit clears the H counter. This bit always reads as 0.

BIDIR_H

Direction select

0 (UP): Up. The H counter counts up to its limit condition, then is cleared to zero.

1 (UPDOWN): Up-down. The H counter counts up to its limit, then counts down to a limit condition or to 0.

PRE_H

Specifies the factor by which the SCT clock is prescaled to produce the H counter clock. The counter clock is clocked at the rate of the SCT clock divided by PRELH+1. Clear the counter (by writing a 1 to the CLRCTR bit) whenever changing the PRE value.

RESERVED

Reserved

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