Datasheet

ST7540 Functional description
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Table 12. Control register functions
Function Value Selection Note Default
0 to 2 Frequencies
Bit2 Bit1 Bit0
60 KHz
66 KHz
72 KHz
76 KHz
82.05 KHz
86 KHz
110 KHz
132.5 KHz
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
132.5 kHz
3 to 4 Baud rate
Bit 4 Bit 3
600
1,200
2,400
4,800
0
0
1
1
0
1
0
1
2400
5Deviation
Bit 5
0.5
1
0
1
0.5
6 Watchdog
Bit 6
Disabled
Enabled (1.5 s)
0
1
Enabled
7 to 8
Transmission
time out
Bit 8 Bit 7
Disabled
1 s
3 s
Not Used
0
0
1
1
0
1
0
1
1 sec
9 to 10
Frequency
detection time
Bit 10 Bit 9
500 µs
1 ms
3 ms
5 ms
0
0
1
1
0
1
0
1
1 ms
11 Reserved Do not force a different value 0