Hi Nick,
Refer to https://trustedcomputinggroup.org/wp-content/uploads/TPM-Main-Part-3-Commands_v1.2_rev116_01032011.pdf for details.Can you cite the relevant section?
Just pick any section that describes a TPM command. I randomly used Section 10.3 for TPM Unbind. See the 'Incoming operands and sizes' table.
Regards, -Denis