4 external signals, External signals -3 – Freescale Semiconductor MCF5480 User Manual
Page 419

External Signals
MCF548x Reference Manual, Rev. 3
Freescale Semiconductor
17-3
Figure 17-2. Multiplexed FlexBus Implementation
17.4
External Signals
This section describes the external signals that are involved in data transfer operations.
summarizes the MCF548x FlexBus signals.
Table 17-1. FlexBus Signal Summary
Signal Name
Direction
Description
Reset State
FBCS[5:0]
O
General purpose chip-selects
Hi-Z
AD[31:0]
I/O
Address / Data bus
Hi-Z
ALE
O
Address Latch Enable
Hi-Z
BE/BWE[3:0]
O
Byte Selects
Hi-Z
OE
O
Output Enable
Hi-Z
R/W
O
Read/Write. 1 = Read, 0 = Write
Hi-Z
TBST
O
Burst Transfer indicator
Hi-Z
TSIZ[1:0]
O
Transfer Size
Hi-Z
TA
I
Transfer Acknowledge
—
AD[31:0]
FlexBus
Interface
Controller
DATA
[31:Y]
ADDR[X:0]
Address
Latch
Logic
External Device / Peripheral
ALE
R/W
TA
FBCSx
ALE
R/W
TA
CS
BE/BWE[3:0]
BE/BWE[3:0]
OE
OE
SIZ[1:0]
TSIZ[1:0]
TBST
BURST