Motorola Espresso Maker MC68340 ユーザーズマニュアル
2- 14
MC68340 USER’S MANUAL
MOTOROLA
Table 2-5. Signal Summary
Signal Name
Mnemonic
Input/Output
Active State
Three-State
Address Bus
A23–A0
Out
—
Yes
Address Bus Port A7–A0/
Interrupt Acknowledge
Interrupt Acknowledge
A31–A24
Out/I/O/Out
—/—/Low
Yes
Data Bus
D15–D0
I/O
—
Yes
Function Codes
FC3–FC0
Out
—
Yes
Chip Select 3/Interrupt Request
Level/Port B4, B2, B1
Level/Port B4, B2, B1
CS3–CS1
Out/In/I/O
Low/Low/—
No
Chip Select 0/Autovector
CS0
Out/In
Low/Low
No
Bus Request
BR
In
Low
—
Bus Grant
BG
Out
Low
No
Bus Grant Acknowledge
BGACK
In
Low
—
Data and Size Acknowledge
DSACK1,
DSACK0
In
Low
—
Read-Modify-Write Cycle
RMC
Out
Low
Yes
Address Strobe
AS
Out
Low
Yes
Data Strobe
DS
Out
Low
Yes
Size
SIZ1, SIZ0
Out
—
Yes
Read/Write
R/
W
Out
High/Low
Yes
Interrupt Request Level/
Port B7, B6, B5, B3
Port B7, B6, B5, B3
IRQ7, IRQ6,
IRQ5, IRQ3
In/I/O
Low/—
—
Reset
RESET
I/O
Low
No
Halt
HALT
I/O
Low
No
Bus Error
BERR
In
Low
—
System Clock
CLKOUT
Out
—
No
Crystal Oscillator
EXTAL, XTAL
In, Out
—
—
External Filter Capacitor
XFC
In
—
—
Clock Mode Select/Port B0
MODCK
In/I/O
—/—
—
Instruction Fetch/
Development Serial In
Development Serial In
IFETCH
/DSI
Out/In
Low/—
No/—
Instruction Pipe/
Development Serial Out
Development Serial Out
IPIPE
/DSO
Out/Out
Low/—
No/—
Breakpoint/
Development Serial Clock
Development Serial Clock
BKPT
/DSCLK
In/In
Low/—
—/—
Freeze
FREEZE
Out
High
No
Receive Data
RxDA, RxDB
In
—
—
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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