Figure 73. Wait Mode Conversion (Continuous Mode, Software Trigger) - ST STM32WL55JC Reference Manual

RM0453
18.7 Analog window watchdog (AWD1EN, AWD1SGL, AWD1CH,
ADC_AWDxCR, ADC_AWDxTR)
The three AWD analog watchdogs monitor whether some channels remain within a
configured voltage range (window).
18.7.1 Description of analog watchdog 1
AWD1 analog watchdog is enabled by setting the AWD1EN bit in the ADC_CFGR1 register.
It is used to monitor that either one selected channel or all enabled channels (see
Analog watchdog 1 channel
shown in
The AWD1 analog watchdog status bit is set if the analog voltage converted by the ADC is
below a lower threshold or above a higher threshold. These thresholds are programmed in
HT1[11:0] and LT1[11:0] bits of ADC_AWD1TR register. An interrupt can be enabled by
setting the AWD1IE bit in the ADC_IER register.
The AWD1 flag is cleared by software by programing it to 1.
When converting data with a resolution of less than 12-bit (according to bits DRES[1:0]), the
LSB of the programmed thresholds must be kept cleared because the internal comparison
is always performed on the full 12-bit raw converted data (left aligned).
Table 106
Analog Watchdog comparison between:
Resolution
bits
Raw converted
RES[1:0]
data, left aligned
00: 12-bit DATA[11:0]
01: 10-bit DATA[11:2],00
10: 8-bit DATA[11:4],0000
11: 6-bit DATA[11:6],000000 LTx[11:0] and HTx[11:0]
1. The watchdog comparison is performed on the raw converted data before any alignment calculation.
Table 107
register to enable the analog watchdog on one or more channels.
selection) remain within a configured voltage range (window) as
Figure 76.
describes how the comparison is performed for all the possible resolutions.
Table 106. Analog watchdog comparison
Thresholds
(1)
LTx[11:0] and HTx[11:0] -
LTx[11:0] and HTx[11:0] The user must configure LTx[1:0] and HTx[1:0] to "00"
LTx[11:0] and HTx[11:0]
shows how to configure the AWD1SGL and AWD1EN bits in the ADC_CFGR1
Figure 76. Analog watchdog guarded area
Analog voltage
Higher threshold
Lower threshold
The user must configure LTx[3:0] and HTx[3:0] to
"0000"
The user must configure LTx[5:0] and HTx[5:0] to
"000000"
Guarded area
RM0453 Rev 2
Analog-to-digital converter (ADC)
Comments
HTx
LTx
Table 107:
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