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Action-Qualifier Submodule Registers

Figure 4-8. Counter-Compare Control Register (CMPCTL)

15

 

 

 

 

10

9

8

 

 

Reserved

 

 

SHDWBFULL

SHDWAFULL

 

 

 

R-0

 

 

R-0

R-0

7

6

5

4

3

2

1

0

Reserved

SHDWBMODE

Reserved

SHDWAMODE

LOADBMODE

 

LOADAMODE

R-0

R/W-0

R-0

R/W-0

R/W-0

 

R/W-0

LEGEND: R/W = Read/Write; R = Read only; -n = value after reset

Table 4-8. Counter-Compare Control Register (CMPCTL) Field Descriptions

Bits

Name

Value

Description

15-10

Reserved

 

Reserved

9

SHDWBFULL

 

Counter-compare B (CMPB) Shadow Register Full Status Flag

 

 

 

This bit self clears once a load-strobe occurs.

 

 

0

CMPB shadow FIFO not full yet

 

 

1

Indicates the CMPB shadow FIFO is full; a CPU write will overwrite current shadow value.

8

SHDWAFULL

 

Counter-compare A (CMPA) Shadow Register Full Status Flag

 

 

 

The flag bit is set when a 32-bit write to CMPA:CMPAHR register or a 16-bit write to CMPA

 

 

 

register is made. A 16-bit write to CMPAHR register will not affect the flag.

 

 

 

This bit self clears once a load-strobe occurs.

 

 

0

CMPA shadow FIFO not full yet

 

 

1

Indicates the CMPA shadow FIFO is full, a CPU write will overwrite the current shadow

 

 

 

value.

7

Reserved

 

Reserved

6

SHDWBMODE

 

Counter-compare B (CMPB) Register Operating Mode

 

 

0

Shadow mode. Operates as a double buffer. All writes via the CPU access the shadow

 

 

 

register.

 

 

1

Immediate mode. Only the active compare B register is used. All writes and reads directly

 

 

 

access the active register for immediate compare action.

5

Reserved

 

Reserved

4

SHDWAMODE

 

Counter-compare A (CMPA) Register Operating Mode

 

 

0

Shadow mode. Operates as a double buffer. All writes via the CPU access the shadow

 

 

 

register.

 

 

1

Immediate mode. Only the active compare register is used. All writes and reads directly

 

 

 

access the active register for immediate compare action

3-2

LOADBMODE

 

Active Counter-Compare B (CMPB) Load From Shadow Select Mode

 

 

 

This bit has no effect in immediate mode (CMPCTL[SHDWBMODE] = 1).

 

 

00

Load on CTR = Zero: Time-base counter equal to zero (TBCTR = 0x0000)

 

 

01

Load on CTR = PRD: Time-base counter equal to period (TBCTR = TBPRD)

 

 

10

Load on either CTR = Zero or CTR = PRD

 

 

11

Freeze (no loads possible)

1-0

LOADAMODE

 

Active Counter-Compare A (CMPA) Load From Shadow Select Mode.

 

 

 

This bit has no effect in immediate mode (CMPCTL[SHDWAMODE] = 1).

 

 

00

Load on CTR = Zero: Time-base counter equal to zero (TBCTR = 0x0000)

 

 

01

Load on CTR = PRD: Time-base counter equal to period (TBCTR = TBPRD)

 

 

10

Load on either CTR = Zero or CTR = PRD

 

 

11

Freeze (no loads possible)

4.3Action-Qualifier Submodule Registers

Figure 4-9through Figure 4-12and Table 4-9through Table 4-12provide the action-qualifier submodule register definitions.

SPRU791D–November 2004–Revised October 2007

Registers

99

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Texas Instruments 28xxx Action-Qualifier Submodule Registers, Counter-Compare Control Register Cmpctl Field Descriptions