SWRA682 December   2020 CC1310 , CC1312PSIP , CC1312R , CC1314R10 , CC1350 , CC1352P , CC1352P7 , CC1352R , CC1354P10 , CC1354R10

 

  1.   Trademarks
  2. 1 Introduction
  3. 2 Recommended Test Setup
  4. 3 Overrides
  5. 4 Find the Needed RX BW
  6. 5 How to Set the Deviation
  7. 6 Theoretical Sensitivity
  8. 7 Determine AGC_REF Level
  9. 8 Determine Anti-Aliasing BW
  10. 9 Determine PA Ramp Settings
  11. 10Intermediate Frequency (IF)
  12. 11LNA Ib Offset
  13. 12Sensitivity and Selection of Sync Word
  14. 13Narrowband
    1. 13.1 Frequency Offset Tolerance
    2. 13.2 Low Datarate
    3. 13.3 Phase Noise
  15. 14RSSI Offset

13.2 Low Datarate

The default deviation resolution is 250 Hz. If the wanted deviation is not a factor of 250 Hz the resolution can be changed. Setting modulation.deviationStepSz = 2 as part of the CMD_PROP_RADIO_DIV_SETUP settings sets the deviation resolution to 15.625 Hz.

Due to how the modem is designed not all datarates are valid for a given RXBW setting. SmartRF Studio can be used to find if the planned combination of datarate, deviation and RX BW is possible. If one or more values are outside the valid range the tool will give an error message and the valid range.

These limits can be modified by using bit repetition. This is covered in detail in this app note: CC13x0 Low Data Rate Operation

For CC13x2 bit repetition doesn’t require a separate patch. To turn the bit repition on, set .formatConf.fecMode = 0x2 under CMD_PROP_RADIO_DIV_SETUP. The repition factor is set through the following override:

HW_REG_OVERRIDE(0x5324,0x000X)

Where x is the wanted factor.