Texas Instruments CC112 Series, User Manual, Page: 76 / 109

CC112X/CC1175
SWRU295C Page 76 of 108
DRATE1 - Data Rate Configuration Mantissa [15:8]
Bit no. Name Reset R/W Description
7:0 DATARATE_M_15_8 0xA9 R/W Data Rate (mantissa part [15:8]). See
DRATE2
DRATE0 - Data Rate Configuration Mantissa [7:0]
Bit no. Name Reset R/W Description
7:0 DATARATE_M_7_0 0x2A R/W Data Rate (mantissa part [7:0]). See
DRATE2
AGC_REF - AGC Reference Level Configuration
Bit no. Name Reset R/W Description
7:0 AGC_REFERENCE 0x36 R/W AGC Reference Level. The AGC reference level must be higher than the minimum
SNR to the demodulator. The AGC reduces the analog front end gain when the
magnitude output from channel filter > AGC reference level. An optimum AGC
reference level is given by several conditions, but a rule of thumb is to use the
formula:
4 ) BW Filter RX ( log 10 _
10
REFERENCE AGC
RX Filter BW
AGC_REFERENCE
10 kHz 0x24
20 kHz 0x27
50 kHz 0x2B
200 kHz 0x31
For Zero-IF configuration, AGC hysteresis > 3 dB, or modem format which needs
SNR > 15 dB a higher AGC reference value is needed.
AGC_CS_THR - Carrier Sense Threshold Configuration
Bit no. Name Reset R/W Description
7:0 AGC_CS_THRESHOLD 0x00 R/W AGC Carrier Sense Threshold. Two's complement number with 1 dB resolution
AGC_GAIN_ADJUST - RSSI Offset Configuration
Bit no. Name Reset R/W Description
7:0 GAIN_ADJUSTMENT 0x00 R/W AGC Gain Adjustment. This register is used to adjust
RSSI[11:0]
to the actual
carrier input signal level to compensate for interpolation gains (two's complement
with 1 dB resolution)
AGC_CFG3 - AGC Configuration
Bit no. Name Reset R/W Description
7 RSSI_STEP_THR 0x01 R/W AGC has a built in function to signal if there has been a step in the RSSI value
0 RSSI threshold is 3 dB
1 RSSI threshold is 6 dB
6:5 AGC_ASK_BW 0x00 R/W Controls the bandwidth of the data filter in ASK/OOK mode (this register field is not
used for other modulation formats)
00 No data filter
01 1/64 IIR filter
10 1/256 IIR filter
11 1/1024 IIR filter
4:0 AGC_MIN_GAIN 0x11 R/W AGC Minimum Gain. Limits the AGC minimum gain compared to the preset gain
table range. AGC_MIN_GAIN can have a value in the range 0 to 17 when
AGC_CFG2.FE_PERFORMANCE_MODE = 00b
or
01b
and 0 to 13 when
AGC_CFG2.FE_PERFORMANCE_MODE = 10b