Low-Voltage Inhibit (LVI)
Functional Description
MC68HC908GP32
•
MC68HC08GP32
—
Rev. 6
Technical Data
MOTOROLA
Low-Voltage Inhibit (LVI)
191
An LVI reset also drives the RST pin low to provide low-voltage
protection to external peripheral devices.
Figure 14-1. LVI Module Block Diagram
14.4.1 Polled LVI Operation
In applications that can operate at V
DD
levels below the V
TRIPF
level,
software can monitor V
DD
by polling the LVIOUT bit. In the configuration
register, the LVIPWRD bit must be at logic 0 to enable the LVI module,
and the LVIRSTD bit must be at logic 1 to disable LVI resets.
LOW V
DD
DETECTOR
LVIPWRD
STOP INSTRUCTION
LVISTOP
LVI RESET
LVIOUT
V
DD
> LVI
Trip
= 0
V
DD
≤
LVI
Trip
= 1
FROM CONFIG
FROM CONFIG1
V
DD
FROM CONFIG1
LVIRSTD
LVI5OR3
FROM CONFIG1
Addr.
Register Name
Bit 7
6
5
4
3
2
1
Bit 0
$FE0C
LVI Status Register
(LVISR)
Read: LVIOUT
0
0
0
0
0
0
0
Write:
Reset:
0
0
0
0
0
0
0
0
= Unimplemented
Figure 14-2. LVI I/O Register Summary
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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