Does the CRC_ERROR pin in Cyclone® IV devices need a pull-up resistor? - Does the CRC_ERROR pin in Cyclone® IV devices need a pull-up resistor? Description Yes, the CRC_ERROR pin in Cyclone® IV GX devices needs to be connected to an external 10-K. pull-up resistor to an acceptable voltage. Resolution In the Quartus® II software Settings --> Device --> Device and Pin Options --> Error Detection CRC, you can check/uncheck the " Enable Open Drain on CRC Error pin " checkbox. The CRC_ERROR pin is always open drain regardless of this checkbox. This is a Quartus II software problem in versions 9.1, 9.1 SP1, and 9.1 SP2, the checkbox should be grayed out. It is grayed out in version 10.0 onwards. Custom Fields values: ['novalue'] Troubleshooting - False ['novalue'] ['novalue'] novalue novalue ['Cyclone® IV GX FPGA'] ['novalue'] ['novalue'] ['novalue']