MC68HC812A4 Datasheet, PDF (125/342 Pages) Motorola, Inc – 16-bit device composed of standard on-chip peripheral modules connected by an intermodule bus. Modules include

Advance Information
MOTOROLA
Memory Expansion and Chip-Select
Generation of Chip-Selects
INTERNAL SPACE
$0000
$0100
$0200
$0300
RAM
1 KBYTE
$0400
$0500
$0600
$0700
$0800
$0900 REGISTERS
$0A00
$0B00
$0C00
$0D00
$0E00
$0F00
$0FFF
EXTERNAL SPACE
CS3
1 KBYTE
CS0
256 BYTES
CS1
128 BYTES
CS2
128 BYTES
Figure 8-1. Chip-Selects CS3–CS0 Partial Memory Map
Register
INITRM
INITRG
WINDEF
MXAR
Table 8-2. Example Register Settings
Value
$00
$08
$20
$00
Meaning
Assigns internal RAM to $0000–$0FFF
Assigns register block to $0800–$09FF and
register-following chip-selects at $0A00–$0BFF
Enable EPAGE
No port G lines assigned as extended address
Memory Expansion and Chip-Select
MC68HC812A4 — Rev. 3.0
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