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S i 4 4 3 0
144
Preliminary Rev. 0.4
Reset value = 00000000
Reset value = 01110101
The RF carrier frequency can be calculated as follows:
f
carrier
= (f
b
+24+(f
c
+f
o
) / 64000) x 10000 x 2+ (f
hch
x f
hs
x 10) [kHz],
where parameters f
c
, f
o
, f
b
and hb_sel come from registers 73h–77h. Parameters f
hch
and f
hs
come from register
79h and 7Ah.
Register 74h. Frequency Offset 2
Bit
D7
D6
D5
D4
D3
D2
D1
D0
Name
Reserved
fo[9:8]
Type
R
R/W
Bit
Name
Function
7:2
Reserved
Reserved.
1:0
fo[9:8]
Upper Bits of the Frequency Offset Setting.
fo[9] is the sign bit. The frequency offset can be calculated as Offset = 312.5 Hz x fo[7:0].
fo[9:0] is a twos complement value. Reading from this register will give the AFC correc-
tion last results, not this register value.
Register 75h. Frequency Band Select
Bit
D7
D6
D5
D4
D3
D2
D1
D0
Name
Reserved
sbsel
Reserved
fb[4:0]
Type
R
R/W
R/W
R/W
Bit
Name
Function
7
Reserved
Reserved.
6
sbsel
Side Band Select.
5
Reserved
Reserved.
This bit must always be written to 1.
4:0
fb[4:0]
Frequency Band Select.
Every increment corresponds to a 20 MHz band.
fb=21
900–919.9 MHz
fb=22
920–939.9 MHz
fb=23
940–960 MHz