Before we use the TPM, we must first take ownership of it. Taking ownership establishes an owner password for maintenance operations and a password for one of the root keys inside the TPM, the Storage Root Key (SRK) (pronounced shark). You can set the administrator password to any password you want, but to work with legacy software, you'll want to set the SRK to the well-known password of twenty zeros. You can set a unique SRK password if you want, but the TrouSerS software, the software used to control the TPM, includes a command-line parameter to set the password to its well-known value for a reason. First install tpm-tools:

sudo apt-get install tpm-tools

Then you should restart your BBB with the CryptoCape attached. This will ensure that the TPM kernel driver and associate software load correctly. To check if everything is working properly issue the following command:

dmesg | grep TPM

This should return:

[    5.370109] tpm_i2c_atmel 1-0029: Issuing TPM_STARTUP...