Hi,
I’ve received a LimeSDR Mini a few months back and I am now trying to make it work using Luaradio on a Raspberry Pi 3 B+. I’ve installed the latest versions (from the myriad/drivers repo for artful) of the Limesuite and SoapySDR packages. I’ve cloned the luaradio repo and I am trying to run a simple Luaradio script for receiving FM. The LimeSDR mini is connected via its Y cable to 2 USB ports on the Raspberry Pi.
Whenever I run the luaradio script, this is the output I get:
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linux; GNU C++ version 6.2.0 20161010; Boost_106100; UHD_003.009.005-0-unknown
[INFO] Make connection: ‘USB 2.0 (LimeSDR Mini)’
Claimed Interface
[INFO] Device name: uLimeSDR
[INFO] Reference: 30.72 MHz
[INFO] Init LMS7002M(0)
LMS7002M values cache at /root/.limesuite/LMS7002M_cache_values.db
[INFO] Ver=7, Rev=1, Mask=1
[INFO] LMS7002M calibration values caching Enable
CGEN: Freq=80 MHz, VCO=2.4 GHz, INT=77, FRAC=131072, DIV_OUTCH_CGEN=14
[INFO] SoapyLMS7::setFrequency(Rx, 0, BB, 0 MHz)
[INFO] SoapyLMS7::setFrequency(Tx, 0, BB, 0 MHz)
[INFO] SoapyLMS7::setAntenna(Rx, 0, LNAL)
[INFO] SoapyLMS7::setAntenna(Tx, 0, BAND1)
[INFO] SoapyLMS7::setGain(Rx, 0, PGA, 0 dB)
[INFO] SoapyLMS7::setGain(Rx, 0, LNA, 0 dB)
[INFO] SoapyLMS7::setGain(Rx, 0, TIA, 0 dB)
[INFO] SoapyLMS7::setGain(Tx, 0, PAD, -50 dB)
[INFO] SoapyLMS7::setSampleRate(Rx, 0, 10 MHz), CGEN=80 MHz, ADC=20 MHz, decim=2
CGEN: Freq=80 MHz, VCO=2.4 GHz, INT=77, FRAC=131072, DIV_OUTCH_CGEN=14
[ERROR] SetFrequencyCGEN(80 MHz) failed:
INT: 77 FRAC: 131072 DIV_OUTCH_CGEN: 14
VCO: 2400 MHz RefClk: 30.72 MHz
TuneVCO(CGEN) - VCO too low
Connection_uLimeSDR::UpdateExternalDataRate(tx=20MHz, rx=10MHz)
----- FPGA PLL #0 CONFIG -----
M=112, N=7, Fvco=640.000 MHz
C0=16, Fout=40.000 MHz, CNT_IND=2, nSteps=0, phaseShift=0.0
C1=16, Fout=40.000 MHz, CNT_IND=3, nSteps=32, phaseShift=90.0
C2=32, Fout=20.000 MHz, CNT_IND=4, nSteps=0, phaseShift=0.0
C3=32, Fout=20.000 MHz, CNT_IND=5, nSteps=64, phaseShift=90.0
[INFO] SoapyLMS7::setSampleRate(Tx, 0, 10 MHz), CGEN=80 MHz, DAC=20 MHz, interp=2
CGEN: Freq=80 MHz, VCO=2.4 GHz, INT=77, FRAC=131072, DIV_OUTCH_CGEN=14
[ERROR] SetFrequencyCGEN(80 MHz) failed:
INT: 77 FRAC: 131072 DIV_OUTCH_CGEN: 14
VCO: 2400 MHz RefClk: 30.72 MHz
TuneVCO(CGEN) - VCO too low
Connection_uLimeSDR::UpdateExternalDataRate(tx=10MHz, rx=10MHz)
----- FPGA PLL #0 CONFIG -----
M=93, N=3, Fvco=620.000 MHz
C0=31, Fout=20.000 MHz, CNT_IND=2, nSteps=0, phaseShift=0.0
C1=31, Fout=20.000 MHz, CNT_IND=3, nSteps=62, phaseShift=90.0
C2=31, Fout=20.000 MHz, CNT_IND=4, nSteps=0, phaseShift=0.0
C3=31, Fout=20.000 MHz, CNT_IND=5, nSteps=62, phaseShift=90.0
[INFO] SoapyLMS7::setBandwidth(Rx, 0, 30 MHz)
CGEN: Freq=332.56 MHz, VCO=2.66048 GHz, INT=85, FRAC=633514, DIV_OUTCH_CGEN=3
[ERROR] setBandwidth(Rx, 0, 30 MHz) Failed - SetFrequencyCGEN(332.56 MHz) failed:
INT: 85 FRAC: 633514 DIV_OUTCH_CGEN: 3
VCO: 2660.48 MHz RefClk: 30.72 MHz
TuneVCO(CGEN) - VCO too low
[SoapySDRSource] Block runtime error: ./radio/blocks/sources/soapysdr.lua:354: Making device: SetFrequencyCGEN(332.56 MHz) failed:
INT: 85 FRAC: 633514 DIV_OUTCH_CGEN: 3
VCO: 2660.48 MHz RefClk: 30.72 MHz
TuneVCO(CGEN) - VCO too low
stack traceback:
[C]: in function ‘error’
./radio/blocks/sources/soapysdr.lua:354: in function ‘initialize_soapysdr’
./radio/blocks/sources/soapysdr.lua:497: in function ‘process’
./radio/core/block.lua:372: in function ‘run’
./radio/core/composite.lua:563: in function <./radio/core/composite.lua:563>
[C]: in function ‘xpcall’
./radio/core/composite.lua:563: in function ‘start’
./radio/core/composite.lua:456: in function ‘run’
fm.lua:37: in main chunk
[C]: in function ‘dofile’
./luaradio:105: in main chunk
[C]: at 0x00013bf8
libusb: warning [libusb_exit] application left some devices open
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What does this “VCO too low” error mean? How can it be prevented?