Datasheet

PIC18F87J50 FAMILY
DS39775C-page 114 © 2009 Microchip Technology Inc.
7.6.4 16-BIT MODE TIMING
The presentation of control signals on the External
Memory Bus is different for the various operating
modes. Typical signal timing diagrams are shown in
Figure 7-4 and Figure 7-5.
FIGURE 7-4: EXTERNAL MEMORY BUS TIMING FOR TBLRD (EXTENDED
MICROCONTROLLER MODE)
FIGURE 7-5: EXTERNAL MEMORY BUS TIMING FOR SLEEP (EXTENDED
MICROCONTROLLER MODE)
Q2Q1 Q3 Q4 Q2Q1 Q3 Q4
Q2Q1 Q3 Q4
A<19:16>
ALE
OE
AD<15:0>
CE
Opcode Fetch Opcode Fetch Opcode Fetch
TBLRD *
TBLRD Cycle 1
ADDLW 55h
from 000100h
Q2Q1 Q3 Q4
0Ch
CF33h
TBLRD 92h
from 199E67h
9256h
from 000104h
Memory
Cycle
Instruction
Execution
INST(PC – 2)
TBLRD Cycle 2
MOVLW 55h
from 000102h
MOVLW
Q2Q1 Q3 Q4 Q2Q1 Q3 Q4
A<19:16>
ALE
OE
3AAAh
AD<15:0>
00h
00h
CE
Opcode Fetch
Opcode Fetch
SLEEP
SLEEP
from 007554h
Q1
Bus Inactive
0003h
3AABh
0E55h
Memory
Cycle
Instruction
Execution
INST(PC – 2)
Sleep Mode,
MOVLW 55h
from 007556h