General YARR Documentation and Applications

YARR Docs

YARR readout for ITkPixV1.1 Quad module at SLAC 

YARR Test Bench for Testing and GUI Dev

SLAC Local Setups

There are two YARR PC's set up at SLAC currently:

(1) Larger YARR PC with 1 Spec PCIe card in B33 Reception area (node name BigYARRPC_Eth) 

(2) Smaller HyperX/noctua/Corsair "FELIX" workstation with 1 Spec PCIe card in Lab C. (node name spectest)


If you get this error in YARR even after flashing the firmware: 

[18:46:45:565][  info  ][  specComTest  ]: Init spec

[18:46:45:565][  info  ][    SpecCom    ]: Opening SPEC with id #0

[18:46:45:565][critical][    SpecCom    ]: Error during initilisation:  Open failed

[18:46:45:565][critical][    SpecCom    ]: Fatal Error! Aborting!

It is probably due to an issue with permissions. Just do: 

sudo chmod 666 /dev/spec0

or write a udev rules file for a more permanent solution:

echo 'KERNEL=="spec[0-9]*", MODE="666"' | sudo tee -a /etc/udev/rules.d/99-spec.rules



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