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Hi,
We have developed a Transparent mode design with the CC1120 to work with a legacy FM design in a 25 KHz channel with 4KHz deviation. We use SRX and STX to switch between Tx/Rx and find that the Tx comes up pretty quick (25usec) but Rx takes about 170usec to come on.
The CC1120 datasheet says Tx/Rx turnaround time is typically 50usec.
Can anybody PLEASE HELP and point us to the registers to look at to speed up the Rx turn on time.
Best regards,
BP
Thank you for the quick reply TER.
The data being available after 50 us would be great, but we measure this 170 us delay on the TRX_SW pin 18. This line is used to control an external LNA which adds another small delay.
We use CS (on GPIO1) with an external circuit to gate (mute) the Rx data from GPIO3. For some reason CS is asserted initially then goes low for about 6ms and the Rx data is "muted" then data is output after several ms When CS goes high again and we are trying to figure out what could be the problem.
I have attached the SMARTRF file that we used to export register settings. Hope you can help identify the problem.
BP
<?xml version="1.0" encoding="ISO-8859-1"?>
<!DOCTYPE configuration SYSTEM "C:/Program Files (x86)/Texas Instruments/SmartRF Tools/SmartRF Studio 7/config/xml/configdata.dtd"[]>
<dcpanelconfiguration>
<Devicename>CC1120</Devicename>
<Description>Saved configuration data</Description>
<registersettings>
<Register>
<Name>AGC_CFG0</Name>
<Value>0xcf</Value>
</Register>
<Register>
<Name>AGC_CFG1</Name>
<Value>0x0a</Value>
</Register>
<Register>
<Name>AGC_CFG2</Name>
<Value>0x22</Value>
</Register>
<Register>
<Name>AGC_CS_THR</Name>
<Value>0x8f</Value>
</Register>
<Register>
<Name>AGC_GAIN_ADJUST</Name>
<Value>0x93</Value>
</Register>
<Register>
<Name>AGC_REF</Name>
<Value>0x2d</Value>
</Register>
<Register>
<Name>CHAN_BW</Name>
<Value>0x0d</Value>
</Register>
<Register>
<Name>DCFILT_CFG</Name>
<Value>0x1c</Value>
</Register>
<Register>
<Name>DEVIATION_M</Name>
<Value>0x27</Value>
</Register>
<Register>
<Name>FIFO_CFG</Name>
<Value>0x00</Value>
</Register>
<Register>
<Name>FREQ2</Name>
<Value>0x6d</Value>
</Register>
<Register>
<Name>FREQOFF_CFG</Name>
<Value>0x33</Value>
</Register>
<Register>
<Name>FS_CAL0</Name>
<Value>0x0e</Value>
</Register>
<Register>
<Name>FS_CAL1</Name>
<Value>0x40</Value>
</Register>
<Register>
<Name>FS_CFG</Name>
<Value>0x18</Value>
</Register>
<Register>
<Name>FS_DIG0</Name>
<Value>0x5f</Value>
</Register>
<Register>
<Name>FS_DIG1</Name>
<Value>0x00</Value>
</Register>
<Register>
<Name>FS_DIVTWO</Name>
<Value>0x03</Value>
</Register>
<Register>
<Name>FS_DSM0</Name>
<Value>0x33</Value>
</Register>
<Register>
<Name>FS_DVC0</Name>
<Value>0x17</Value>
</Register>
<Register>
<Name>FS_PFD</Name>
<Value>0x50</Value>
</Register>
<Register>
<Name>FS_PRE</Name>
<Value>0x6e</Value>
</Register>
<Register>
<Name>FS_REG_DIV_CML</Name>
<Value>0x14</Value>
</Register>
<Register>
<Name>FS_SPARE</Name>
<Value>0xac</Value>
</Register>
<Register>
<Name>FS_VCO0</Name>
<Value>0xb4</Value>
</Register>
<Register>
<Name>IF_MIX_CFG</Name>
<Value>0x00</Value>
</Register>
<Register>
<Name>IOCFG0</Name>
<Value>0x30</Value>
</Register>
<Register>
<Name>IOCFG1</Name>
<Value>0x11</Value>
</Register>
<Register>
<Name>IOCFG2</Name>
<Value>0x08</Value>
</Register>
<Register>
<Name>IOCFG3</Name>
<Value>0x09</Value>
</Register>
<Register>
<Name>IQIC</Name>
<Value>0xc6</Value>
</Register>
<Register>
<Name>MDMCFG0</Name>
<Value>0x6a</Value>
</Register>
<Register>
<Name>MDMCFG1</Name>
<Value>0x06</Value>
</Register>
<Register>
<Name>MODCFG_DEV_E</Name>
<Value>0x0b</Value>
</Register>
<Register>
<Name>PA_CFG0</Name>
<Value>0x7e</Value>
</Register>
<Register>
<Name>PA_CFG1</Name>
<Value>0x54</Value>
</Register>
<Register>
<Name>PA_CFG2</Name>
<Value>0x5e</Value>
</Register>
<Register>
<Name>PKT_CFG0</Name>
<Value>0x20</Value>
</Register>
<Register>
<Name>PKT_CFG1</Name>
<Value>0x00</Value>
</Register>
<Register>
<Name>PKT_CFG2</Name>
<Value>0x03</Value>
</Register>
<Register>
<Name>PREAMBLE_CFG1</Name>
<Value>0x00</Value>
</Register>
<Register>
<Name>SERIAL_STATUS</Name>
<Value>0x08</Value>
</Register>
<Register>
<Name>SETTLING_CFG</Name>
<Value>0x03</Value>
</Register>
<Register>
<Name>SYMBOL_RATE2</Name>
<Value>0x53</Value>
</Register>
<Register>
<Name>SYNC0</Name>
<Value>0xaa</Value>
</Register>
<Register>
<Name>SYNC1</Name>
<Value>0xaa</Value>
</Register>
<Register>
<Name>SYNC2</Name>
<Value>0xaa</Value>
</Register>
<Register>
<Name>SYNC3</Name>
<Value>0xaa</Value>
</Register>
<Register>
<Name>SYNC_CFG0</Name>
<Value>0x03</Value>
</Register>
<Register>
<Name>SYNC_CFG1</Name>
<Value>0x1f</Value>
</Register>
<Register>
<Name>XOSC1</Name>
<Value>0x03</Value>
</Register>
<Register>
<Name>XOSC5</Name>
<Value>0x0e</Value>
</Register>
</registersettings>
<dcpanel>
<Property name="m_chkRegView" role="44">2</Property>
<Property name="m_chkRfParameters" role="44">2</Property>
<Property name="m_tabUserMode" role="37">1</Property>
<Property name="m_easyModeSettings" role="33">-1</Property>
<Property name="m_typicalSettings" role="33">-1</Property>
<Property name="m_testFuncPanel" role="37">1</Property>
</dcpanel>
<rfparameters>
<Property name="m_cmbFrontends" role="46">0</Property>
<Property name="m_chkHGMorBYP" role="44">2</Property>
<Property name="m_cmbEmRevs" role="46">-1</Property>
<Property name="Xtal frequency" role="46">32.000000</Property>
</rfparameters>
<conttx>
<Property name="m_rbtModulated" role="45">1</Property>
<Property name="m_rbtUnmodulated" role="45">0</Property>
<Property name="m_cmbDataFormat" role="46">1</Property>
<Property name="m_chkFreqSweep" role="44">0</Property>
<Property name="m_chkChanSweep" role="44">0</Property>
</conttx>
<contrx>
<Property name="m_cmbDataFormat" role="46">1</Property>
<Property name="m_chkAutoScroll" role="44">2</Property>
</contrx>
<packettx>
<Property name="m_edtPayloadSize" role="42">30</Property>
<Property name="m_edtPacketCount" role="42">100</Property>
<Property name="m_edtPacketCountEsy" role="42">100</Property>
<Property name="m_edtRandomPacketData" role="42">13 0d 89 0a 1c db ae 32 20 9a 50 ee 40 78 36 fd 12 49 32 f6 9e 7d 49 dc ad 4f 14 f2 </Property>
<Property name="m_edtPacketData" role="42"></Property>
<Property name="m_edtAccessAddress" role="42"></Property>
<Property name="m_edtDeviceAddress" role="42"></Property>
<Property name="m_chkAddSeqNbr" role="44">2</Property>
<Property name="m_chkInfinite" role="44">0</Property>
<Property name="m_chkInfiniteEsy" role="44">0</Property>
<Property name="m_rbtRandom" role="45">1</Property>
<Property name="m_rbtText" role="45">0</Property>
<Property name="m_rbtHex" role="45">0</Property>
<Property name="m_chkAdvanced" role="44">0</Property>
</packettx>
<packetrx>
<Property name="m_edtPacketCount" role="42">100</Property>
<Property name="m_edtPacketCountEsy" role="42">100</Property>
<Property name="m_edtAccessAddress" role="42"></Property>
<Property name="m_chkInfinite" role="44">0</Property>
<Property name="m_chkInfiniteEsy" role="44">0</Property>
<Property name="m_cmbViewFormat" role="46">0</Property>
<Property name="m_chkSeqNbrIncluded" role="44">2</Property>
<Property name="m_edtDumpFile" role="42"></Property>
<Property name="m_chkAdvanced" role="44">0</Property>
<Property name="m_chk802154gMode" role="44">0</Property>
</packetrx>
<commandpanel>
<Property name="m_chkInsertLength" role="44">0</Property>
<Property name="m_edtTxFifo" role="42"></Property>
<Property name="m_edtRxFifo" role="42"></Property>
<Property name="m_cmbInstrInput" role="46">-1</Property>
</commandpanel>
<packetRxSniffMode>
<Property name="m_edtPreambleLength" role="42">8</Property>
<Property name="m_edtCarrierSenseThreshold" role="42">-90</Property>
<Property name="m_rbtRssi" role="45">1</Property>
<Property name="m_rbtPreamble" role="45">0</Property>
</packetRxSniffMode>
</dcpanelconfiguration>