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equipment:embedded:voipac_pxa270_baseboard
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Voipac PXA270 Baseboard
Pxa270 DMA
- 32 DMA channels, DMA[31:0]
- supports flow-through and fly-by transfer
- 32 channels, 68 PBP (peripherial-bus peripherals) requests, 3 IBP (internal-bus peripherals, only quick-capture interface in this chip) requests, and 3 external device requests.
Приотритеты каналов
| Set | Channels | Priority | Number of Times Served |
|---|---|---|---|
| 0 | 0, 1, 2, 3, 16, 17, 18, 19 | I (High) | 4/8 |
| 1 | 4, 5, 6, 7, 20, 21, 22, 23 | II | 2/8 |
| 2 | 8, 9, 10, 11, 24, 25, 26, 27 | III | 1/8 |
| 3 | 12, 13, 14, 15, 28, 29, 30, 31 | IV | 1/8 |
Flow-through DMA
For a flow-through DMA read/write from/to an internal peripheral, use the following settings for the DMA controller register bits:
Read: DCMDx[FLYBYS] and DCMDx[FLYBYT] = 0 DSADRx[SRCADDR] = memory address DTADRx[TRGADDR] = internal peripheral address DCMDx[INCSRCADDR] = 1 DCMDx[INCTRGADDR] = 0 DCMDx[FLOWSRC] = 0 DCMDx[FLOWTRG] = 1 Write: DCMDx[FLYBYS] and DCMDx[FLYBYT] = 0 DSADRx[SRCADDR] = internal peripheral address DTADRx[TRGADDR] = memory address DCMDx[INCSRCADDR] = 0 DCMDx[INCTRGADDR] = 1 DCMDx[FLOWSRC] = 1 DCMDx[FLOWTRG] = 0
equipment/embedded/voipac_pxa270_baseboard.1327385807.txt.gz · Последние изменения: 2012/11/30 12:38 (внешнее изменение)
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