CC2500RGPR Datasheet, PDF (65/99 Pages) Texas Instruments – Low-Cost Low-Power 2.4 GHz RF Transceiver

CC2500
Bit Field Name
7:5 Reserved
4:0 FREQ_IF[4:0]
0x0B: FSCTRL1 – Frequency Synthesizer Control
Reset
R/W Description
15 (0x0F)
R0
R/W The desired IF frequency to employ in RX. Subtracted from FS
base frequency in RX and controls the digital complex mixer in
the demodulator.
f _IF

f _XOSC
2¹⁰
 FREQ _ IF
The default value gives an IF frequency of 381 kHz, assuming
a 26.0 MHz crystal.
Bit Field Name
7:0 FREQOFF[7:0]
0x0C: FSCTRL0 – Frequency Synthesizer Control
Reset
R/W Description
0 (0x00) R/W Frequency offset added to the base frequency before being
used by the FS. (2’s complement).
Resolution is FXTAL/2¹⁴ (1.59 - 1.65 kHz); range is ±202 kHz to
±210 kHz, dependent of XTAL 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 FXOSC/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
SWRS040C
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