LPC43XX DMA channel config register

[robberpen]

Hi

Based on Table 350. DMA Channel Configuration registers (CONFIG[0:7] 

Bit 0

• If set b'0 to 1, then the DMA will start transfer?
• If DMA transfer completed, this b'0 will auto set from 1 to 0?

Bit 18

• If I want to setup DMA request signal, should I set to b'18 to 0 and b'0 to 0 ? then I can expect  DMA channel will enable/activate to startup transfer when DMA_request signal arrival?

[xiangjun_rong]

Hi,

Bit 0

Q1)If set b'0 to 1, then the DMA will start transfer?

>>>>>Yes

Q2)If DMA transfer completed, this b'0 will auto set from 1 to 0?

>>>>I do not think the bit will update to 0 automatically after DMA transfer completed.

Bit 18

Q3)If I want to setup DMA request signal, should I set to b'18 to 0 and b'0 to 0 ? then I can expect  DMA channel will enable/activate to startup transfer when DMA_request signal arrival?

>>>>The bit 0 is DMA channel enable bit, the bit 18 is DMA channel request enable bit, if you want to DMA work, both bits must be enabled.

Hope it can help you

BR

Xiangjun Rong

[robberpen]

Hi

After my tested.

• bit0 will automatically reset to 0, after transfer completed
• no matter bit18 is 0 or 1, DMA always begin transfer.  but I will like to DMA waitting DMA_req siganl to stat transfer. is any idea?

Regards

[xiangjun_rong]

Hi,

does the DMA work or not?

BR

XiangJun Rong

[robberpen]

DMA is working at b'0 is immediate. but I want to DMA trigger by DMA_req with bust mode.