Debug Features
457
SLAU367P – October 2012 – Revised April 2020
Copyright © 2012–2020, Texas Instruments Incorporated
Ultrasonic Sensing Solution (USS, USS_A)
Table 18-4. Control Signals Among USS Submodules (continued)
Source
Signal
Receiver
Function
Condition to Generate the Signal
ASQ
ASQ_PPGTRG
PPG
Start pulse generation
SAPHATM_A register
ASQ_PPGSTOP
Stop pulse generation immediately
PSQ_STOP = 1 and PPG is active
ASQ_ACQARM
SDHS
Power up SDHS
SAPHATM_B register
ASQ_ACQTRG
Conversion start
SAPHATM_D register
ASQ_SDHSSTOP
Conversion stop and power off
PSQ_STOP = 1
ASQ_PDREQ
PSQ
USS power down, PSQ can receive
a new USS_PWRREQ signal
If SAPHASCTL1.ESOFF = 1 and
SAPHASCTL1.STDBY = 0 when
SDHS_ACQDONE = 1
ASQ_STDBYREQ
USS standby, USS power down,
PSQ can receive a new
USS_PWRREQ signal
If SAPHASCTL1.ESOFF = 1 and
SAPHASCTL1.STDBY = 1 when
SDHS_ACQDONE = 1
ASQ_ACQDONE
PSQ can receive a new
USS_PWRREQ signal
SDHS_ACQDONE = 1
SDHS
SDHS_ACQDONE
ASQ
Signal to ASQ that SDHS data
conversion is complete
When the preconfigured sample size
has been captured
18.3 Debug Features
When the device enters debug mode, the USS module automatically stops the existing measurement, and
all interrupts are suppressed. The debugger can read or write any USS registers, but
SDHSCTL4.SDHSON and SDHSCTL5.SSTART are not functional. The PSQ ignores the USS_PWRREQ
signal.