Texas Instruments MSP430x1xx, Руководство пользователя

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SVS Registers
6-7 Supply Voltage Supervisor
6.3 SVS Registers
The SVS registers are listed in Table 6−1.
Table 6−1. SVS Registers
Register Short Form Register Type Address Initial State
SVS Control Register SVSCTL Read/write 055h Reset with BOR
SVSCTL, SVS Control Register
7 6 5 4 3 2 1 0
VLDx PORON SVSON SVSOP SVSFG
rw−0† rw−0† rw−0† rw−0† rw−0† r r rw−0†
† Reset by a brownout reset only, not by a POR or PUC.
VLDx Bits
7-4 Voltage level detect. These bits turn on the SVS and select the nominal SVS
threshold voltage level. See the device−specific datasheet for parameters.
0000 SVS is off
0001 1.9 V
0010 2.1 V
0011 2.2 V
0100 2.3 V
0101 2.4 V
0110 2.5 V
0111 2.65 V
1000 2.8 V
1001 2.9 V
1010 3.05
1011 3.2 V
1100 3.35 V
1101 3.5 V
1110 3.7 V
1111
Compares external input voltage SVSIN to 1.2 V.
PORON Bit 3 POR on. This bit enables the SVSFG flag to cause a POR device reset.
0
SVSFG does not cause a POR
1 SVSFG causes a POR
SVSON
Bit 2 SVS on. This bit reflects the status of SVS operation. This bit DOES NOT turn
on the SVS. The SVS is turned on by setting VLDx > 0.
0
SVS is Off
1 SVS is On
SVSOP
Bit 1 SVS output. This bit reflects the output value of the SVS comparator.
0
SVS comparator output is high
1 SVS comparator output is low
SVSFG Bit 0 SVS flag. This bit indicates a low voltage condition. SVSFG remains set after
a low voltage condition until reset by software or a brownout reset.
0
No low voltage condition occurred
1 A low condition is present or has occurred