DS89C420-ENL MAXIM [Maxim Integrated Products], DS89C420-ENL Datasheet - Page 27

• Manufacturer Part Number: DS89C420-ENL
• Description: Ultra-High-Speed Microcontroller
• Manufacturer: MAXIM [Maxim Integrated Products]

Figure 6. PAGE MODE 1, EXTERNAL MEMORY CYCLE (CD1:CD0 = 10)
Internal Memory Cycles
RD / WR
XTAL1
RD / WR
RD / WR
PSEN
Port 0
Port 2
ALE
PSEN
PSEN
Port 0
Port 2
Port 0
Port 2
ALE
ALE
MSB
Page Miss
MSBAdd
LSB
Page Miss
Inst
MSBAdd
LSB
Inst
Page Hit
LSB Add
LSB
MOVX
External Memory Cycles
Page Miss
MOVX
LSB
MOVX executed
27 of 58
MOVX
Page Hit
LSB Add
MSB
Data Access
Inst
MOVX executed
LSB Add
LSB
Data
MSBAdd
Inst
MSB
Page Miss
Data Access
MOVX executed
LSB
Inst
LSB Add
Data Access
MSB
Data
Data Access
LSB Add
LSB
next instruction
Data
Page Miss
MSBAdd
Data
MSB
PAGES=00
PAGES=01
PAGES=10
DS89C420