GD32F20x User Manual
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Figure 18-49. Single pulse mode TIMERx_CHxCV = 0x04 TIMERx_CAR=0x60
TIMER_CK(CNT_CLK)
CEN
CNT_REG
00
01
02
03
04
05
…
.
5F
60
00
O2CPRE
CI3
Under SPM, count er stop
Timers interconnection
Refer to
Advanced timer (TIMERx, x=0, 7)
Timer DMA mode
Timer’s DMA mode is the function that configures timer’s register by DMA module. The
relative registers are TIMERx_DMACFG and TIMERx_DMATB; Of course, you have to
enable a DMA request which will be asserted by some internal interrupt event. When the
interrupt event was asserted, TIMERx will send a request to DMA, which is configured to M2P
mode and PADDR is the TIMERx_DMATB register address, then DMA will access the
TIMERx_DMATB. In fact, register TIMERx_DMATB is only a buffer; timer will map the
TIMERx_DMATB to an internal register, appointed by the field of DMATA in
TIMERx_DMACFG. If the field of DMATC in TIMERx_DMACFG is 0(1 transfer), then the
timer’s DMA request is finished. While if TIMERx_DMATC is not 0, such as 3( 4 transfers),
then timer will send 3 more
requests to DMA, and DMA will access timer’s registers
0x4, 0x8, 0xc at the next 3 accesses to TIMERx_DMATB. In
one word, one time DMA internal interrupt event assert, DMATC+1 times request will be send
by TIMERx.
If one more time DMA request event coming, TIMERx will repeat the process as above.
Timer debug mode
When the Cortex™-M3 halted, and the TIMERx_HOLD configuration bit in DBG_CTL2
register set to 1, the TIMERx counter stops.
Summary of Contents for GD32F20 Series
Page 191: ...GD32F20x User Manual 191 Bits Fields Descriptions 31 0 TRNDATA 31 0 32 Bit Random data ...
Page 290: ...GD32F20x User Manual 290 conversion is ongoing ...
Page 325: ...GD32F20x User Manual 325 15 0 ALRM 15 0 RTC alarm value low ...
Page 385: ...GD32F20x User Manual 385 ...
Page 523: ...GD32F20x User Manual 523 clears AERR bit by writing 0 to it ...