EFM32WG Datasheet, PDF (587/834 Pages) List of Unclassifed Manufacturers – The EFM32WG Wonder Gecko is the ideal choice for demanding 8-, 16-, and 32-bit energy sensitive applications.

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are LETIMERn_COMP0+1. Note that the pulse outputs are delayed by one period relative to the toggle
output. The pulses come at the end of their periods.
Figure 23.6. LETIMER Simple Waveforms Output
Initial configuration
COMP0 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3
CNT 0 3 2 1 0 3 2 1 0 3 2 1 0 3 2 1 0 3 2 1 0 3 2 1 0
Int. flags set
UFIF
UFIF
UFIF
UFIF
UFIF
UFIF
LFACLK_LETIMERn
LETn _O0
UFOA0 = 00
LETn _O0
UFOA0 = 01
LETn _O0
UFOA0 = 10
For the example in Figure 23.7 (p. 587) , the One-shot repeat mode has been selected, and
LETIMERn_REP0 has been written to 3. The resulting behavior is pretty similar to that shown in
Figure 6, but in this case, the timer stops after counting to zero LETIMERn_REP0 times. By using
LETIMERn_REP0 the user has full control of the number of pulses/toggles generated on the output.
Figure 23.7. LETIMER Repeated Counting
Initial configuration
St op
COMP0 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3
CNT 0 3 2 1 0 3 2 1 0 3 2 1 0 0 0 0 0 0 0 0 0 0 0 0 0
REP0 3 3 3 3 3 2 2 2 2 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0
Int. flags set
LFACLK_LETIMERn
LETn _O0
UFOA0 = 00
LETn _O0
UFOA0 = 01
LETn _O0
UFOA0 = 10
UFIF
UFIF
UFIF
REP0 IF
Using the Double repeat mode, output can be generated on both the LETIMER outputs. Figure 23.8 (p.
587) shows an example of this. UFOA0 and UFOA1 in LETIMERn_CTRL are configured for pulse
output and the outputs are configured for low idle polarity. As seen in the figure, the number written to
the repeat registers determine the number of pulses generated on each of the outputs.
Figure 23.8. LETIMER Dual Output
UFOA0 = 10
UFOA1 = 10
REP0 = 2
REP1 = 7
START
REP0 = 3
START
REP0 = 2
REP1 = 3
START
LETn _O0
LETn _O1
2013-05-08 - Wonder Gecko Family - d0233_Rev0.50
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