Specifications

CC1101
SWRS061I Page 76 of 98
0x10: MDMCFG4 – Modem Configuration
Bit
Field Name
Reset
R/W
Description
7:6
CHANBW_E[1:0]
2 (0x02)
R/W
5:4
CHANBW_M[1:0]
0 (0x00)
R/W
Sets the decimation ratio for the delta-sigma ADC input stream and thus the
channel bandwidth.
ECHANBW
XOSC
channel
MCHANBW
f
BW
_
2)·_4(8 

The default values give 203 kHz channel filter bandwidth, assuming a 26.0
MHz crystal.
3:0
DRATE_E[3:0]
12 (0x0C)
R/W
The exponent of the user specified symbol rate
0x11: MDMCFG3 – Modem Configuration
Bit
Field Name
Reset
R/W
Description
7:0
DRATE_M[7:0]
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:
 
XOSC
EDRATE
DATA
f
MDRATE
R 


28
_
2
2_256
The default values give a data rate of 115.051 kBaud (closest setting to 115.2
kBaud), assuming a 26.0 MHz crystal.