2.0 SIGNAL DESCRIPTION
Change Figure 3-3 on Page 3-2.
V
A23-A0
D15-D0
ADDRESS BUS
DATA BUS
CC
GND
CLK
AS
FC0
FC1
FC2
R/W
UDS
LDS
PROCESSOR
STATUS
ASYNCHRONOUS
BUS CONTROL
DTACK
MC68SEC000
BR
BG
BUS ARBITRATION
CONTROL
IPL0
IPL1
BERR
RESET
HALT
SYSTEM
CONTROL
INTERRUPT
CONTROL
IPL2
AVEC
MODE
Figure 1. Input and Output Signals (MC68EC000 and MC68SEC000)
2.1 Data Bus (D15-D0)
In Section 3.2 on page 3-4, replace “The MC68EC000 and MC68HC001 use D7-D0 in 8-bit mode, and D15-
D8 are undefined.” with “Using the MC68HC001, MC68EC000, and MC68SEC000 mode pin, you can
statically select either 8- or 16-bit modes for data transfer. The MC68EC000, MC68SEC000, and
MC68HC001 use D7-D0 in 8-bit mode. D15-D8 are undefined.”
2.2 Bus Arbitration Control
In Section 3.4 on page 3-5, the sentence “In the 48-pin version of the MC68008 and MC68EC000, no pin is
available for the bus grant acknowledge signal; this microprocessor uses a two-wire bus arbitration
scheme.” should read “In the 64-pin MC68EC000 and MC68SEC000, no pin is available for the bus grant
acknowledge signal. These microprocessors use a two-wire bus arbitration scheme.”
2.3 System Control
The Mode subsection heading of Section 3.6 on page 3-7 should read ‘‘Mode (MODE) (MC68HC001/
68EC000/68SEC000).’’
2.4 MC68SEC000 Low-Power Mode
Add the following to Sections 4 and 5, Bus Operation.
The MC68SEC000 has been redesigned to provide fully static- and low-power operation. This section
describes the recommended method for placing the MC68SEC000 into a low-power mode to reduce the
4
M68000 USER’S MANUAL ADDENDUM
MOTOROLA
MOTOROLA [ MOTOROLA ]
