PowerPC 405GP Embedded Processor Data Sheet
Signal Functional Description (Part 4 of 8)
Multiplexed signals are shown in brackets following the first signal name assigned to each multiplexed ball.
Notes:
1. Receiver input has hysteresis.
2. Must pull up. See “Pull-Up and Pull-Down Resistors” on page 33 for recommended termination values.
3. Must pull down. See “Pull-Up and Pull-Down Resistors” on page 33 for recommended termination values.
4. If not used, must pull up.
5. If not used, must pull down.
6. Strapping input during reset; pull up or pull down as required.
7. Pull-up may be required. See “External Bus Control Signals” on page 33.
Signal Name
Description
I/O
Type
Notes
Peripheral write enable. Low when any of the four PerWBE0:3
write byte enables are low.
5V tolerant
3.3V PCI
[PerWE]PCIINT
O
or
PCI interrupt. Open-drain output (two states; 0 or open circuit)
5V tolerant
3.3V LVTTL
PerCS0
Peripheral chip select bank 0.
O
7
Seven additional peripheral chip selects
or
5V tolerant
3.3V LVTTL
PerCS1:7[GPIO10:16]
O[I/O]
1, 7
General Purpose I/O. To access this function, software must
toggle a DCR bit.
Used by either the peripheral controller or the DMA controller
depending upon the type of transfer involved. When the
PPC405GP is the bus master, it enables the selected device to
drive the bus.
5V tolerant
3.3V LVTTL
PerOE
O
7
1
Used by the PPC405GP when not in external master mode, as
output by either the peripheral controller or DMA controller
depending upon the type of transfer involved. High indicates a
read from memory, low indicates a write to memory.
5V tolerant
3.3V LVTTL
PerR/W
I/O
Otherwise it used by the external master as an input to indicate
the direction of data transfer.
5V tolerant
3.3V LVTTL
PerReady
PerBLast
Used by a peripheral slave to indicate it is ready to transfer data.
I
1
Used by the PPC405GP when not in external master mode,
otherwise used by external master. Indicates the last transfer of a
memory access.
5V tolerant
3.3V LVTTL
I/O
1, 7
DMAReq0:3 are used by slave peripherals to indicate they are
prepared to transfer data.
5V tolerant
3.3V LVTTL
DMAReq0:3
DMAAck0:3
I
1
6
1
DMAAck0:3 are used by the PPC405GP to cause the DMA
peripheral to transfer data.
5V tolerant
3.3V LVTTL
O
5V tolerant
3.3V LVTTL
EOT0:3/TC0:3
End Of Transfer/Terminal Count.
I/O
Page 37 of 60
6/20/03
IBM [ IBM ]
