eCAP Registers
1949
SPNU563A – March 2018
Copyright © 2018, Texas Instruments Incorporated
Enhanced Capture (eCAP) Module
33.5.7 ECAP Control Register 2 (ECCTL2)
Figure 33-20. ECAP Control Register 2 (ECCTL2) [offset = 28h]
15
11
10
9
8
Reserved
APWMPOL
CAP_APWM
SWSYNC
R-0
R/W-0
R/W-0
R/W-0
7
6
5
4
3
2
1
0
SYNCO_SEL
SYNCI_EN
TSCTRSTOP
REARM
STOP_WRAP
CONT_ONESHT
R/W-0
R/W-0
R/W-0
R/W-0
R/W-3h
R/W-0
LEGEND: R/W = Read/Write; R = Read only; -
n
= value after reset
Table 33-8. ECAP Control Register 2 (ECCTL2) Field Descriptions
Bits
Field
Value
Description
15-11
Reserved
0
Reserved
10
APWMPOL
APWM output polarity select. This is applicable only in APWM operating mode.
0
Output is active-high (Compare value defines high time).
1
Output is active-low (Compare value defines low time).
9
CAP_APWM
CAP/APWM operating mode select.
0
ECAP module operates in capture mode. This mode forces the following configuration:
• Inhibits TSCTR resets via CTR = PRD event
• Inhibits shadow loads on CAP1 and 2 registers
• Permits user to enable CAP1-4 register load
• CAPx/APWMx pin operates as a capture input
1
ECAP module operates in APWM mode. This mode forces the following configuration:
• Resets TSCTR on CTR = PRD event (period boundary
• Permits shadow loading on CAP1 and 2 registers
• Disables loading of time-stamps into CAP1-4 registers
• CAPx/APWMx pin operates as a APWM output
8
SWSYNC
Software-forced Counter (TSCTR) Synchronizing. This provides a convenient software method to
synchronize some or all ECAP time bases. In APWM mode, the synchronizing can also be done via
the CTR = PRD event.
0
Writing a 0 has no effect. Reading always returns a 0.
1
Writing a 1 forces a TSCTR shadow load of current ECAP module and any ECAP modules down-
stream providing the SYNCO_SEL bits are 0,0. After writing a 1, this bit returns to a 0.
Note: Selection CTR = PRD is meaningful only in APWM mode; however, you can choose it in CAP
mode if you find doing so useful.
7-6
SYNCO_SEL
Sync-Out select.
0
Select sync-in event to be the sync-out signal (pass through).
1h
Select CTR = PRD event to be the sync-out signal.
2h
Disable sync out signal.
3h
Disable sync out signal.
5
SYNCI_EN
Counter (TSCTR) Sync-In select mode.
0
Disable sync-in option.
1
Enable counter (TSCTR) to be loaded from CTRPHS register upon either a SYNCI signal or a S/W
force event.
4
TSCTRSTOP
Time Stamp (TSCTR) Counter Stop (freeze) Control.
0
TSCTR is stopped.
1
TSCTR is free-running.