Motorola ColdFire MCF5281 User Manual
Page 243
Signal Descriptions
Freescale Semiconductor
14-3
lists the external signals grouped by functionality.
NOTE
The primary functionality of a pin is not necessarily its default functionality.
Pins that are muxed with GPIO will default to their GPIO functionality.
Table 14-1. MCF5282 Signal Description
Signal Name
Abbreviation
Function
I/O
Page
External Memory Interface
Address
A[23:0]
Define the address of external byte,
word, longword, and 16-byte burst
accesses.
I/O
Data
D[31:0]
Data bus. Provide the general purpose
data path between the MCU and all
other devices.
I/O
Byte strobes
BS[3:0]
Define the byte lane of data on the
data bus.
I/O
Output enable
OE
Indicates when an external device can
drive data on the bus.
O
Transfer acknowledge
TA
Indicates that the external data
transfer is complete and should be
asserted for one clock.
I
Transfer error
acknowledge
TEA
Indicates that an error condition exists
for the bus transfer.
I
Read/Write
R/W
Indicates the direction of the data
transfer on the bus.
I/O
Transfer size
SIZ[1:0]
Specify the data access size of the
current external bus reference.
O
Transfer start
TS
Asserted during the first CLKOUT
cycle of a transfer when address and
attributes are valid.
O
Transfer in progress
TIP
Asserted to indicate that a bus transfer
is in progress. Negated during idle bus
cycles.
O
Chip selects
CS[6:0]
Programmed for a base address
location and for masking addresses,
port size and burst capability
indication, wait state generation, and
internal/external termination.
O
SDRAM Controller Signals
SDRAM row
address strobe
SRAS
SDRAM synchronous row address
strobe.
O
SDRAM column
address strobe
SCAS
SDRAM synchronous column address
strobe.
O
MCF5282 and MCF5216 ColdFire Microcontroller User’s Manual, Rev. 3