Chapter 3 |
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| Pin # | Signal | Description (P1 Row D) |
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| 31 (D10) | DAck5* | DMA Acknowledge 5 – Used by DMA controller to select the I/O |
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| resource requesting the bus, or to request ownership of the bus as a bus |
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| master device. Can also be used by the ISA bus master to gain control of |
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| the bus from the DMA controller. |
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| 32 (D11) | DRQ5 | DMA Request 5 – Used by I/O resources to request DMA service. Must |
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| be held high until associated DACK5 line is active. |
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| 33 (D12) | DAck6* | DMA Acknowledge 6 – Used by DMA controller to select the I/O |
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| resource requesting the bus, or to request ownership of the bus as a bus |
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| master device. Can also be used by the ISA bus master to gain control of |
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| the bus from the DMA controller. |
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| 34 (D13) | DRQ6 | DMA Request 6 – Used by I/O resources to request DMA service. Must |
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| be held high until associated DACK6 line is active. |
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| 35 (D14) | DAck7* | DMA Acknowledge 7 – Used by DMA controller to select the I/O |
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| resource requesting the bus, or to request ownership of the bus as a bus |
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| master device. Can also be used by the ISA bus master to gain control of |
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| the bus from the DMA controller. |
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| 36 (D15) | DRQ7 | DMA Request 7 – Used by I/O resources to request DMA service. Must |
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| be held high until associated DACK7 line is active. |
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| 37 (D16) | +5V | +5V Power +/- 10% |
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| 38 (D17) | Master* | Bus Master Assert – This signal is used by an ISA board along with a |
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| DRQ line to gain ownership of the ISA bus. Upon receiving a |
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| device can pull |
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| address, data, and control lines. After |
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| should wait one CLK period before driving the address and data lines, |
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| and two clock periods before issuing a read or write command. |
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| 39 (D18) | GND | Ground |
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| 40 (D19) | GND | Ground |
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Notes: The shaded area denotes power or ground. The signals marked with * indicate active low.
26 | Reference Manual | CoreModule 420 |