CC2550_13 Datasheet, PDF (43/61 Pages) Texas Instruments – Low-Cost Low-Power 2.4 GHz RF Transmitter

CC2550
Bit Field Name
7:0 CHAN[7:0]
0x0A: CHANNR – Channel Number
Reset
R/W Description
0 (0x00)
R/W The 8-bit unsigned channel number, which is multiplied by
the channel spacing setting and added to the base
frequency.
Bit Field Name
7:6 FREQ[23:22]
5:0 FREQ[21:16]
0x0D: FREQ2 – Frequency Control Word, High Byte
Reset R/W Description
1 (01)
30
(0x1E)
R
FREQ[23:22] is always binary 01 (the FREQ2 register is in the range
85 to 95 with 26-27 MHz crystal)
R/W FREQ[23:0] is the base frequency for the frequency synthesiser in
increments of F_XOSC/2¹⁶.
[ ] f_carrier
=
f _XOSC
2¹⁶
⋅ FREQ
23 : 0
Bit Field Name
7:0 FREQ[15:8]
0x0E: FREQ1 – Frequency Control Word, Middle Byte
Reset
R/W Description
196 (0xC4) R/W Ref. FREQ2 register
Bit Field Name
7:0 FREQ[7:0]
0x0F: FREQ0 – Frequency Control Word, Low Byte
Reset
R/W Description
236 (0xEC) R/W Ref. FREQ2 register
Bit Field Name
7:4 Reserved
3:0 DRATE_E[3:0]
0x10: MDMCFG4 – Modulator Configuration
Reset
R/W Description
R0 Defined in the transceiver version
12 (1100) R/W The exponent of the user specified symbol rate
Bit Field Name
7:0 DRATE_M[7:0]
0x11: MDMCFG3 – Modulator Configuration
Reset
R/W Description
34 (0x22)
R/W The mantissa of the user specified symbol rate. The symbol
rate is configured using an unsigned, floating-point number
with 9-bit mantissa and 4-bit exponent. The 9^th bit is a
hidden ‘1’. The resulting data rate is:
( ) _{RDATA =}
256 + DRATE _ M
2²⁸
⋅ 2^{DRATE _ E} _{⋅ f XOSC}
The default values give a data rate of 115.051 kBaud
(closest setting to 115.2 kBaud), assuming a 26.0 MHz
crystal.
SWRS039B
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