mc68hc912bd32 Freescale Semiconductor, Inc, mc68hc912bd32 Datasheet - Page 51

• Manufacturer Part Number: mc68hc912bd32
• Description: 16-bit Device Composed Of Standard On-chip Peripherals
• Manufacturer: Freescale Semiconductor, Inc

MODE — Mode Register
5-mode
RESET:
RESET:
RESET:
RESET:
RESET:
RESET:
RESET:
SMODN
Bit 7
1
1
0
0
0
1
0
MODB
6
0
1
0
1
1
0
0
most cases will remain cycle deterministic. Refer to 16 Development
Support for more details on BDM.
MODE controls the MCU operating mode and various configuration
options. This register is not in the map in peripheral mode
SMODN, MODB, MODB — Mode Select Special, B and A
ESTR — E Clock Stretch Enable
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.
Read anytime. SMODN may only be written if SMODN = 0 (in special
modes) but the first write is ignored; MODB, MODA may be written
once if SMODN = 1; anytime if SMODN = 0, except that special
peripheral and reserved modes cannot be selected.
Determines if the E Clock behaves as a simple free-running clock or
as a bus control signal that is active only for external bus cycles.
ESTR is always one in expanded modes since it is required for
address demultiplexing and must follow stretched cycles.
Freescale Semiconductor, Inc.
For More Information On This Product,
MODA
0 = E never stretches (always free running).
1 = E stretches high during external access cycles and low during
Operating Modes and Resource Mapping
5
1
1
1
1
0
0
0
non-visible internal accesses.
Go to: www.freescale.com
ESTR
4
1
1
1
1
1
1
1
IVIS
3
0
0
1
1
1
0
1
EBSWAI
2
0
0
0
0
0
0
0
Operating Modes and Resource Mapping
1
0
–
–
–
–
–
–
–
MC68HC912BD32 Rev 1.0
Background Debug Mode
EME
Bit 0
0
0
1
1
1
0
1
Normal Exp
Normal Exp
Special Exp
Special Exp
Single Chip
Single Chip
Peripheral
Normal
Special
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