Two type of protocol frame can be implemented with comStudio:
Commands are frames that can be sent (on user request) from the PC to the target device through the communication channel. It can be used not just to send a command but also to set the value of device register or similar actions (it depend on the protocol implemented).
Receive frames are frames that can be send by the target device and have to be decoded by the PC. It is possible to set one receive frame of this list as expected frame coming from the target device after a command sent by the PC.
It is also possible to set one command that has to be triggered after receiving a frame.