MOTOROLA
M68040 USER’S MANUAL
A-7
MC68LC040
REV2.3 (01/29/2000)
When the MC68LC040 writes or reads a stack frame, it uses long-word operand transfers
wherever possible. Using a long-word-aligned stack pointer greatly enhances exception pro-
cessing performance. The processor does not necessarily read or write the stack frame data
in sequential order. The system software should not depend on a particular exception gen-
erating a particular stack frame. For compatibility with future devices, the software should be
able to handle any format of stack frame for any type of exception. The MC68LC040 does
not generate the floating-point post-instruction stack frame. The MC68040 cannot accept the
eight-word unimplemented stack frame. The MC68LC040 can handle all MC68040 stack
frame formats.
A.6 MC68LC040 ELECTRICAL CHARACTERISTICS
The following paragraphs provide information on the maximum rating and thermal charac-
teristics for the MC68LC040. This section is subject to change. For the most recent specifi-
cations, contact a Motorola sales office or complete the registration card at the end of this
manual.
A.6.1 Maximum Ratings
A.6.2 Thermal Characteristics
The MC68040 cannot
generate or read this stack.
Effective address field is
the address of the faulted
instruction operand.
Characteristic
Symbol
Value
Unit
This device contains protective
circuitry against damage due to
high static voltages or electrical
fields; however, it is advised that
normal precautions be taken to
avoid application of any voltages
higher
than
voltages to this maximum-rated
circuit. Reliablity of operation is
enhanced if unused inputs are
tied to an appropriate logic
voltage level (e.g., either GND or
V
CC
).
Supply Voltage
V
CC
–0.3 to +7.0
V
Input Voltage
V
in
–0.5 to +7.0
V
Maximum Operating Junction Temperature
T
J
110
°
C
Minimum Operating Ambient Temperature
T
A
0
°
C
Storage Temperature Range
T
stg
–55 to 150
°
C
Characteristic
Symbol
Value
Rating
Thermal Resistance, Junction to Case—
PGA Package
θ
JC
3
°
C/W
Table 12-1. Eight-Word Stack Frame (Format $4)
15
0
SP
+$02
+$06
+$08
+$0C
STATUS REGISTER
PROGRAM COUNTER
0100
VECTOR OFFSET
EFFECTIVE ADDRESS
PC OF FAULTED
INSTRUCTION