ST STM32F405 Reference Manual page 645

RM0090
Bits 31:16 CCR4[31:16]: High Capture/Compare 4 value (on TIM2 and TIM5).
Bits 15:0 CCR4[15:0]: Low Capture/Compare value
1.
2.
18.4.17 TIMx DMA control register (TIMx_DCR)
Address offset: 0x48
Reset value: 0x0000
15 14 13
Reserved
Bits 15:13 Reserved, must be kept at reset value.
Bits 12:8 DBL[4:0]: DMA burst length
Bits 7:5 Reserved, must be kept at reset value.
Bits 4:0 DBA[4:0]: DMA base address
Example: Let us consider the following transfer: DBL = 7 transfers & DBA = TIMx_CR1. In this
case the transfer is done to/from 7 registers starting from the TIMx_CR1 address.
if CC4 channel is configured as output (CC4S bits):
CCR4 is the value to be loaded in the actual capture/compare 4 register (preload value).
It is loaded permanently if the preload feature is not selected in the TIMx_CCMR register
(bit OC4PE). Else the preload value is copied in the active capture/compare 4 register
when an update event occurs.
The active capture/compare register contains the value to be compared to the counter
TIMx_CNT and signalled on OC4 output.
if CC4 channel is configured as input (CC4S bits in TIMx_CCMR4 register):
CCR4 is the counter value transferred by the last input capture 4 event (IC4). The
TIMx_CCR4 register is read-only and cannot be programmed.
12 11 10 9
DBL[4:0]
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This 5-bit vector defines the number of DMA transfers (the timer recognizes a burst transfer
when a read or a write access is done to the TIMx_DMAR address).
00000: 1 transfer,
00001: 2 transfers,
00010: 3 transfers,
...
10001: 18 transfers.
This 5-bit vector defines the base-address for DMA transfers (when read/write access are
done through the TIMx_DMAR address). DBA is defined as an offset starting from the
address of the TIMx_CR1 register.
Example:
00000: TIMx_CR1,
00001: TIMx_CR2,
00010: TIMx_SMCR,
...
General-purpose timers (TIM2 to TIM5)
8 7 6
Reserved
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RM0090 Rev 18
5 4 3 2
DBA[4:0]
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1 0
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