Digital-to-analog converter (DAC1)
RM0365
397/1080
DocID025202 Rev 7
Note:
(V
REF+
is replaced by V
DDA
on the 64-, 49-, 48- and 32-pin packages)
16.5.4 DAC
trigger
selection
If the TENx control bit is set, conversion can then be triggered by an external event (timer
counter, external interrupt line). The TSELx[2:0] control bits determine which possible
events will trigger conversion as shown in
.
Each time a DAC interface detects a rising edge on the selected timer TRGO output, or on
the selected external interrupt line 9, the last data stored into the DAC_DHRx register are
transferred into the DAC_DORx register. The DAC_DORx register is updated three APB1
cycles after the trigger occurs.
If the software trigger is selected, the conversion starts once the SWTRIG bit is set.
SWTRIG is reset by hardware once the DAC_DORx register has been loaded with the
DAC_DHRx register contents.
Note:
TSELx[2:0] bit cannot be changed when the ENx bit is set. When software trigger is
selected, the transfer from the DAC_DHRx register to the DAC_DORx register takes only
one APB1 clock cycle.
Table 100. External triggers (DAC1)
Source
Type
TSEL[2:0]
TIM6_TRGO event
Internal signal from on-chip
timers
000
TIM3_TRGO event
(1)
1. To select TIM3_TRGO event as DAC1 trigger source, the DAC_ TRIG_RMP bit must be set in
SYSCFG_CFGR1 register.
001
Reserved
010
TIM15_TRGO event
011
TIM2_TRGO event
100
TIM4_TRGO event
101
EXTI line9
External pin
110
SWTRIG
Software control bit
111