Dma Channel X Number Of Data Register (Dma_Cndtrx) (X = 1 - ST STM32F100 Series Reference Manual

RM0041
Bit 4 DIR: Data transfer direction
This bit is set and cleared by software.
0: Read from peripheral
1: Read from memory
Bit 3 TEIE: Transfer error interrupt enable
This bit is set and cleared by software.
0: TE interrupt disabled
1: TE interrupt enabled
Bit 2 HTIE: Half transfer interrupt enable
This bit is set and cleared by software.
0: HT interrupt disabled
1: HT interrupt enabled
Bit 1 TCIE: Transfer complete interrupt enable
This bit is set and cleared by software.
0: TC interrupt disabled
1: TC interrupt enabled
Bit 0 EN: Channel enable
This bit is set and cleared by software.
0: Channel disabled
1: Channel enabled
9.4.4

DMA channel x number of data register (DMA_CNDTRx) (x = 1..7,

where x = channel number)
Address offset: 0x0C + 0d20 × (channel number – 1)
Reset value: 0x0000 0000
31 30 29 28
15 14 13 12
rw rw rw rw
Bits 31:16
Bits 15:0 NDT[15:0]: Number of data to transfer
27 26 25
11 10 9
rw rw rw
Reserved, must be kept at reset value.
Number of data to be transferred (0 up to 65535). This register can only be written when the
channel is disabled. Once the channel is enabled, this register is read-only, indicating the
remaining bytes to be transmitted. This register decrements after each DMA transfer.
Once the transfer is completed, this register can either stay at zero or be reloaded
automatically by the value previously programmed if the channel is configured in auto-
reload mode.
If this register is zero, no transaction can be served whether the channel is enabled or not.
Direct memory access controller (DMA)
24 23 22
Reserved
8 7 6
NDT
rw rw rw
RM0041 Rev 6
21 20 19 18
5 4 3 2
rw rw rw rw
17 16
1 0
rw rw
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