MOTOROLA
M68000 8-/16-/32-BIT MICROPROCESSORS USER'S MANUAL
3- 1
SECTION 3
SIGNAL DESCRIPTION
This section contains descriptions of the input and output signals. The input and output
signals can be functionally organized into the groups shown in Figure 3-1 (for the
MC68000, the MC68HC000 and the MC68010), Figure 3-2 ( for the MC68HC001), Figure
3-3 (for the MC68EC000), Figure 3-4 (for the MC68008, 48-pin version), and Figure 3-5
(for the MC68008, 52-pin version). The following paragraphs provide brief descriptions of
the signals and references (where applicable) to other paragraphs that contain more
information about the signals.
NOTE
The terms assertion and negation are used extensively in this
manual to avoid confusion when describing a mixture of
"active-low" and "active-high" signals. The term assert or
assertion is used to indicate that a signal is active or true,
independently of whether that level is represented by a high or
low voltage. The term negate or negation is used to indicate
that a signal is inactive or false.
VCC(2)
GND(2)
CLK
ADDRESS
BUS
A23–A1
DATA BUS
D15–D0
AS
R/W
UDS
LDS
DTACK
ASYNCHRONOUS
BUS
CONTROL
BR
BG
BGACK
IPL1
IPL2
INTERRUPT
CONTROL
BUS
ARBITRATION
CONTROL
FC1
FC2
E
VMA
VPA
BERR
RESET
HALT
PROCESSOR
STATUS
MC6800
PERIPHERAL
CONTROL
SYSTEM
CONTROL
IPL0
FC0
Figure 3-1. Input and Output Signals
(MC68000, MC68HC000 and MC68010)
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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