This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

CCS/LAUNCHXL-CC13-90: How to set transmit power below 18dBm in 15.4 stack sensor example?

Part Number: LAUNCHXL-CC13-90
Other Parts Discussed in Thread: SMARTRFTM-STUDIO

Tool/software: Code Composer Studio

Hi,

In 15.4 stack/Sensor example, transmit power for CC13-90 is limited to between 18 and 27 dBm:

/*!
 Value for Transmit Power in dBm
 For US and ETSI band, Default value is 10, allowed values are
 -10, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 and 14dBm.
 For China band, allowed values are 6, 10, 13, 14 and 15dBm.
 For CC1190, allowed values are between 18, 23, 25, 26 and 27dBm.
 When the nodes in the network are close to each other
 lowering this value will help reduce saturation */
#ifndef DeviceFamily_CC13X2
#if CONFIG_RANGE_EXT_MODE
#define CONFIG_TRANSMIT_POWER        26

But in Smart RF Studio, TX power can be set below 18dBm. 7, 14, 18 are listed as possible options.

So my question is, how do we set transmit power below 18dBm in Sensor example? Judging from the options in Smart RF studio, this can be done, but it is not enabled/implemented yet in sensor example.

Thanks in advance.

  • Hi Zhiyong,

    This depends on the PHY selected.  EU/ETSI is 12/18/21/23/24/25/26 dBm, US/FCC is 7/14/18/20/22/23/24/25/26.  This is evident in the SMARTRFTM-STUDIO settings and SWRA542/SWRA517.

    Regards,
    Ryan

  • Hi Ryan,

    Thanks for your reply. I actually went through SWRA517 and Smart RF studio a couple of times. The part I am not sure is the limit stated in code comment. Do you mean we can just ignore the lower limit of 18, and enter 7 or 14?

  • Hi Zhiyong,

    The project will build but is still constrained by the TX power tables in mac_user_config_cc13x0_rftable.h, therefore illegitimate values will be ignored.

    Regards,
    Ryan

  • Hi Ryan,

    I assume we can edit the power table according the values provided in Smart RF studio to legitimize 7 and 14 dBm as transmit power. where is this file 

    mac_user_config_cc13x0_rftable.h

    located? I listed all files recursively under the sensor example, the closest file I found is mac_user_config.h

  • Zhiyong, it already allows 7 and 14 dBm for the US PHY.  Do not change or modify this file.

    Regards,
    Ryan

  • Sorry it took me a while to track down the power table. I didn't realize this file is in include path.

    You are right 7&14 dBm are already supported as of SDK 4.10. The limit of 18dBm in code comment is out of date and can be ignored.

    const macTxPwrVal_t txPowerTable_subg_US_CC1310_CC1190[] =
    {
        {7, RF_TxPowerTable_DEFAULT_PA_ENTRY(0, 3, 0, 0) },
        {14, RF_TxPowerTable_DEFAULT_PA_ENTRY(1, 3, 0, 0) },
        {18, RF_TxPowerTable_DEFAULT_PA_ENTRY(2, 3, 0, 0) },
        {20, RF_TxPowerTable_DEFAULT_PA_ENTRY(3, 3, 0, 0) },
        {22, RF_TxPowerTable_DEFAULT_PA_ENTRY(4, 3, 0, 0) },
        {23, RF_TxPowerTable_DEFAULT_PA_ENTRY(5, 3, 0, 0) },
        {24, RF_TxPowerTable_DEFAULT_PA_ENTRY(6, 3, 0, 0) },
        {25, RF_TxPowerTable_DEFAULT_PA_ENTRY(9, 3, 0, 0) },
        {26, RF_TxPowerTable_DEFAULT_PA_ENTRY(14, 3, 0, 0) },
        RF_TxPowerTable_TERMINATION_ENTRY
    };