IBM PowerPC 403GCX
Table 4. 403GCX Signal Descriptions
I/O
Signal
Name
Pin Ball
Function
Type
M10 I/O
N10 I/O
D22
71
72
73
74
75
76
77
78
79
82
Data bus bit 22.
Data bus bit 23.
Data bus bit 24.
Data bus bit 25.
Data bus bit 26.
Data bus bit 27.
Data bus bit 28.
Data bus bit 29.
Data bus bit 30.
Data bus bit 31.
D23
D24
D25
D26
D27
D28
D29
D30
D31
DMAA0
L10 I/O
P11 I/O
M11 I/O
N11 I/O
P12 I/O
M12 I/O
N12 I/O
N13 I/O
156 B4
O
DMA Channel 0 Acknowledge. DMAA0 has an active level when a
transaction is taking place between the 403GCX and a peripheral.
DMAA1
DMAA2
157 A3
158 C3
159 B3
O
O
O
DMA Channel 1 Acknowledge. See description of DMAA0.
DMA Channel 2 Acknowledge. See description of DMAA0.
DMAA3/
XACK
DMA Channel 3 Acknowledge / External Master Transfer Acknowl-
edge. When the 403GCX is bus master, this signal is DMAA3; see
description of DMAA0. When the 403GCX is not the bus master,
this signal is XACK, an output from the 403GCX which has an
active level when data is valid during an external bus master trans-
action.
DMAR0
2
B2
I
DMA Channel 0 Request. External devices request a DMA transfer
on channel 0 by putting a logic 0 on DMAR0.
DMAR1
DMAR2
3
4
5
B1
C2
C1
I
I
I
DMA Channel 1 Request. See description of DMAR0.
DMA Channel 2 Request. See description of DMAR0.
DMAR3/
XREQ
DMA Channel 3 Request. When the 403GCX is the bus master,
external devices request a DMA transfer on channel 3 by putting a
logic 0 on DMAR3. See description of DMAR0.
When the 403GCX is not the bus master, DMAR3 is used as the
XREQ input. The external bus master places a logic 0 on XREQ to
initiate a transfer to the DRAM controlled by the 403GCX DRAM
controller.
DRAMOE
DRAMWE
137 D9
138 B8
O
O
DRAM Output Enable. DRAMOE has an active level when either
the 403GCX or an external bus master is reading from a DRAM
bank.This signal enables the selected DRAM bank to drive the data
bus.
DRAM Write Enable. DRAMWE has an active level when either the
403GCX or an external bus master is writing to a DRAM bank.
11
AMCC [ APPLIED MICRO CIRCUITS CORPORATION ]
