Ampro LittleBoard800 Reference Manual page 39

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Chapter 3
Pin #
Signal
31 (D10) DACK5*
32 (D11) DRQ5
33 (D12) DACK6*
34 (D13) DRQ6
35 (D14) DACK7*
36 (D15) DRQ7
37 (D16) +5V
38 (D17) MASTER*
39 (D18) GND
40 (D19) GND
Notes: The shaded area denotes power or ground. The signals marked with * = Negative true logic.
LittleBoard 800
Descriptions (J1 Row D)
DMA Acknowledge 5 – Used by DMA controller to select the I/O resource
requesting the bus, or to request ownership of the bus as a bus master
device. Can also be used by the ISA bus master to gain control of the bus
from the DMA controller.
DMA Request 5 – Used by I/O resources to request DMA service. Must be
held high until associated DACK5 line is active.
DMA Acknowledge 6 – Used by DMA controller to select the I/O resource
requesting the bus, or to request ownership of the bus as a bus master
device. Can also be used by the ISA bus master to gain control of the bus
from the DMA controller.
DMA Request 6 – Used by I/O resources to request DMA service. Must be
held high until associated DACK6 line is active.
DMA Acknowledge 7 – Used by DMA controller to select the I/O resource
requesting the bus, or to request ownership of the bus as a bus master
device. Can also be used by the ISA bus master to gain control of the bus
from the DMA controller.
DMA Request 7 – Used by I/O resources to request DMA service. Must be
held high until associated DACK7 line is active.
+5 volts ±5% power supply
Bus Master Assert – This signal is used by an ISA board along with a DRQ
line to gain ownership of the ISA bus. Upon receiving a -DACK a device
can pull -MASTER low which will allow it to control the system address,
data, and control lines. After -MASTER is low, the device should wait one
CLK period before driving the address and data lines, and two clock
periods before issuing a read or write command.
Ground
Ground
Reference Manual
Hardware
33

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