MCF5251(2007) View Datasheet(PDF) - Freescale Semiconductor
Part Name
Description
Manufacturer
MCF5251 Datasheet PDF : 32 Pages
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Signal Description
Table 2. Digital and Analog Modules (continued)
Block
Mnemonic
Block Name
Functional
Grouping
Brief Description
UART
USBOTG
Universal
Asynchronous
Receiver
/Transmitter Module
Connectivity
Peripheral
USB 2.0 High-Speed Connectivity
On-The-Go
Peripheral
Three UARTs handle asynchronous serial communication.
The USB module is used for communication to a PC or communication to
slave devices; for example, to download data from a hard disc player to a
flash player, and to other devices.
3 Signal Description
This chapter describes the MCF5251 input and output signals. The signal descriptions as shown in Table 3
are grouped according to relevant functionality. For additional signal information, see “Chapter 2, Signal
Description†in the MCF5251 reference manual.
Table 3. MCF5251 Signal Index
Signal Name
Address
Mnemonic
A[24:1]
A[23]/GPO54
Read-write control
RW
Output enable
OE
Data
Synchronous row
address strobe
Synchronous column
address strobe
SDRAM write enable
SDRAM upper byte
enable
SDRAM lower byte
enable
SDRAM chip selects
SDRAM clock enable
System clock
D[31:16]
SDRAS/GPIO59
SDCAS/GPIO39
SDWE/GPIO38
SDUDQM/GPO53
SDLDQM/GPO52
SD_CS0/GPIO60
BCLKE/GPIO63
BCLK/GPIO40
Function
Input/ Reset
Output State
24 address lines—address 23 is
multiplexed with GPO54 and
address 24 is multiplexed with A20
(SDRAM access only).
Bus write enable—indicates if read
or write cycle in progress.
Output enable for asynchronous
memories connected to chip selects
Data bus used to transfer word data
Row address strobe for external
SDRAM
Column address strobe for external
SDRAM
Write enable for external SDRAM
Upper byte enable—indicates during
write cycle if high byte is written.
Lower byte enable—indicates during
write cycle if low byte is written.
SDRAM chip select
SDRAM clock enable
SDRAM clock output
Out
Out
Out
In/Out
Out
Out
Out
Out
Out
In/Out
Out
In/Out
X
H
negated
Hi-Z
negated
negated
negated
–
–
negated
–
–
MCF5253 ColdFire Processor Data Sheet: Technical Data, Rev. 2.2
6
Freescale Semiconductor
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