MC68HC812A4 Datasheet, PDF (85/342 Pages) Motorola, Inc – 16-bit device composed of standard on-chip peripheral modules connected by an intermodule bus. Modules include

Operating Modes and Resource Mapping
Mode and Resource Mapping Registers
5.5 Mode and Resource Mapping Registers
This section describes the mode and resource mapping registers.
5.5.1 Mode Register
MODE controls the MCU operating mode and various configuration
options. This register is not in the map in peripheral mode.
Address: $000B
Bit 7
6
5
4
3
2
Read:
SMODN MODB MODA ESTR IVIS
0
Write:
Reset States
Special single-chip: 0
0
0
1
1
0
Special expanded narrow: 0
0
1
1
1
0
Peripheral: 0
1
0
1
1
0
Special expanded wide: 0
1
1
1
1
0
Normal single-chip: 1
0
0
1
0
0
Normal expanded narrow: 1
0
1
1
0
0
Normal expanded wide: 1
1
1
1
0
0
Figure 5-1. Mode Register (MODE)
1
Bit 0
EMD
EME
1
1
1
1
1
1
1
1
0
0
0
0
0
0
Read: Anytime
Write: Varies from bit to bit
SMODN, MODB, and MODA — Mode Select Special, B, and A Bits
These bits show the current operating mode and reflect the status of
the BKGD, MODB, and MODA input pins at the rising edge of reset.
SMODN can be written only if SMODN = 0 (in special modes) but the
first write is ignored. MODB and MODA may be written once if
SMODN = 1; anytime if SMODN = 0, except that special peripheral
and reserved modes cannot be selected.
Advance Information
MOTOROLA
Operating Modes and Resource Mapping
MC68HC812A4 — Rev. 3.0
85