Issue with LimeSDR Mini on Rapsberry Pi 3 B+ with luaradio

#1

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:

—8<------8<------8<------8<------8<------8<------8<------8<------8<------8<—
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
—8<------8<------8<------8<------8<------8<------8<------8<------8<------8<—

What does this “VCO too low” error mean? How can it be prevented?

#2

@IgnasJ do you have any suggestions?