MOTOROLA
M68000 8-/16-/32-BIT MICROPROCESSORS USER'S MANUAL
3- 3
IPL2/IPL0
ADDRESS
BUS
A19–A0
DATA BUS
D7–D0
AS
R/W
DS
DTACK
BR
BG
IPL1
E
VPA
ASYNCHRONOUS
BUS
CONTROL
INTERRUPT
CONTROL
BUS
ARBITRATION
CONTROL
MC6800
PERIPHERAL
CONTROL
VCC(2)
GND(2)
CLK
FC0
FC1
FC2
BERR
RESET
HALT
PROCESSOR
STATUS
SYSTEM
CONTROL
MC6808
Figure 3-4. Input and Output Signals (MC68008, 48-Pin Version)
A21–A0
BGACK
IPL2
ADDRESS
BUS
DATA BUS
D7–D0
AS
R/W
DS
DTACK
BR
BG
IPL1
E
VPA
ASYNCHRONOUS
BUS
CONTROL
INTERRUPT
CONTROL
BUS
ARBITRATION
CONTROL
MC6800
PERIPHERAL
CONTROL
VCC
GND(2)
CLK
FC0
FC1
FC2
BERR
RESET
HALT
PROCESSOR
STATUS
SYSTEM
CONTROL
MC68008
IPL0
Figure 3-5. Input and Output Signals (MC68008, 52-Pin Version)
3.1
ADDRESS BUS (A23–A1)
This 23-bit, unidirectional, three-state bus is capable of addressing 16 Mbytes of data.
This bus provides the address for bus operation during all cycles except interrupt
acknowledge cycles and breakpoint cycles. During interrupt acknowledge cycles, address
lines A1, A2, and A3 provide the level number of the interrupt being acknowledged, and
address lines A23–A4 are driven to logic high.
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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