If you have multiple Alveo cards installed on the host machine, use the xbutil list command to find the device ID of your target card. For example:
xbutil list
...
[0] 0000:d8:00.1 xilinx_u250_gen3x16_base_3 user(inst=131)
[1] 0000:af:00.1 xilinx_vck5000-es1_gen3x16_base_2 user(inst=130)
[2] 0000:5e:00.1 xilinx_u50_gen3x16_xdma_201920_3 user(inst=129)
In this example, if your target card is U50, you can find the device ID is 2. You should modify the line 32 of ~/krnl_cbc/host/host_krnl_cbc_test.cpp as follows:
30 // Use 'xbutil list' command to get the device id of the target alveo card if multiple
31 // cards are installed in the system.
32 #define DEVICE_ID 2