[MPC8313]transfer data from PCI to DDR by DMA is slowly

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[MPC8313]transfer data from PCI to DDR by DMA is slowly

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Issac
Contributor I

PCI of this chip is 66MHz@32bits.
Theoretically, it only needs 0.093us to transmit 24K bytes. 

Hower, It needs 0.093us to transmit 24K bytes.

I don't know what's wrong and how tu deal with it.

I I measured the waveforms of frame and irdy, as shown in the following figure.

Blue signal IRDY, green signal FRAME.

1656824287144.jpg

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Issac
Contributor I

Theoretically, it only needs 93us to transmit 24K bytes. 

Hower, It needs 930us to transmit 24K bytes.

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