Sleep Timer Registers; Sleep Timer Capture (Example Using Rising Edge On P0_0) - Texas Instruments CC253x User Manual

Sleep Timer Registers

SLEEPSTA.CLK32K
Figure 11-1. Sleep Timer Capture (Example Using Rising Edge on P0_0)
It is not possible to switch the input-capture pin while capture is enabled. Capture must be disabled before
a new input-capture pin can be selected. To disable capture, follow these steps (note that interrupts are
disabled for up to half of a 32-kHz cycle, or 15.26 µs):
1. Disable interrupts.
2. Wait until SLEEPSTA.CLK32K is high.
3. Set STCC.PORT[1:0] to 3. This disables capture.
11.4 Sleep Timer Registers
The registers used by the Sleep Timer are:
• ST2 – Sleep Timer 2
• ST1 – Sleep Timer 1
• ST0 – Sleep Timer 0
• STLOAD – Sleep Timer load status
• STCC – Sleep Timer capture control
• STCS – Sleep Timer capture status
• STCV0 – Sleep Timer capture value byte 0
• STCV1 – Sleep Timer capture value byte 1
• STCV2 – Sleep Timer capture value byte 2
ST2 (0x97) – Sleep Timer 2
Bit Name Reset R/W
7:0 ST2[7:0] 0x00 R/W
130
Sleep Timer
P0_0
P0IFG[0]
STCS.VALID
STCV[23:0]
Description
Sleep Timer count or compare value. When read, this register returns the high bits [23:16] of the
Sleep Timer count. When writing, this register sets the high bits [23:16] of the compare value. The
value read is latched at the time of reading register ST0. The value written is latched when ST0 is
written.
Copyright © 2009–2014, Texas Instruments Incorporated
Read STCV[23:0],
Then Clear
STCS.VALID
Timer Value is Captured
Clear P0IFG[0] After
Having Detected a
Rising Edge On
SLEEPSTA.CLK32K
T0412-01
SWRU191F – April 2009 – Revised April 2014
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