z86e31 ZiLOG Semiconductor, z86e31 Datasheet - Page 32

• Manufacturer Part Number: z86e31
• Description: Z8 4k Otp Microcontroller
• Manufacturer: ZiLOG Semiconductor

FUNCTIONAL DESCRIPTION (Continued)
Z86E30/E31/E40
Z8 4K OTP Microcontroller
Data Memory (DM). In EPROM Mode, the Z86E40 can
address up to 60 KB of external data memory beginning at
location 4096. In ROMless mode, the Z86E40 can address
up to 64 KB of data memory. External data memory may
be included with, or separated from, the external program
memory space. DM, an optional I/O function that can be
32
65535
4096
4095
0
Not Addressable
External
Memory
EPROM
Figure 23. Data Memory Map
Data
P R E L I M I N A R Y
programmed to appear on pin P34, is used to distinguish
between data and program memory space (Figure 23).
The state of the DM signal is controlled by the type of in-
struction being executed. An LDC opcode references
PROGRAM (DM inactive) memory, and an LDE instruction
references data (DM active Low) memory.
ROMless
External
Memory
Data
DS97Z8X0502
Zilog