© DHBK 2005
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N i dung môn h cộ ọ
N i dung môn h cộ ọ
1. Gi i thi u chung v h vi x lýớ ệ ề ệ ử
2. B vi x lý Intel 8088/8086ộ ử
3. L p trình h p ng cho 8086ậ ợ ữ
4. T ch c vào ra d li uổ ứ ữ ệ
5. Ng t và x lý ng tắ ử ắ
6. Truy c p b nh tr c ti p DMAậ ộ ớ ự ế
7. Các b vi x lý trên th c tộ ử ự ế
© DHBK 2005
2/Chapter6
Ch ng 6: Truy c p b nh tr c ti p DMAươ ậ ộ ớ ự ế
Ch ng 6: Truy c p b nh tr c ti p DMAươ ậ ộ ớ ự ế
•Gi i thi u v DMAớ ệ ề
•M ch DMAC 8237A c a Intelạ ủ
© DHBK 2005
3/Chapter6
Gi i thi u v DMAớ ệ ề
Gi i thi u v DMAớ ệ ề
© DHBK 2005
4/Chapter6
M ch DMAC 8237A c a Intelạ ủ
M ch DMAC 8237A c a Intelạ ủ
© DHBK 2005
5/Chapter6
M ch DMAC 8237A c a Intelạ ủ
M ch DMAC 8237A c a Intelạ ủ
•Although i8237A may not appear as a discrete component in
recent PCs, it’s still there… (integrated in chipsets, ISPC)
•The i8237A has four independent DMA channels
•Original PC/XT design had one i8237A for four DMA channels
•PC/AT used two i8237As to provide 7 DMA channels
•i8237A is programmable device and can be configured for
single transfers, block transfers, Reads, Writes or Memory-to-
Memory transfers