Do you have a tool for calculating the CRC for a command?

You can use the tool from this website: https://www.lammertbies.nl/comm/info/crc-calculation.html

Take this "5669564f746563683200f0fc0009447261667473657276" command string as an example, you can follow the numbered steps as shown in the screenshot below:

make sure to Select the Hex instead of ASCII for this case, and you can find the CRC-CCITT (0xFFFF) 0x72E2. For our NEO and NEO II protocol readers, you just need to switch the 72(MSB) and E2(LSB) so the complete command will be:

5669564f746563683200f0fc0009447261667473657276E272