Hi,
The datasheet you have downloaded is already the complete, full document. The MC33664 does not contain any internal registers and therefore does not require register read/write operations for TPL communication.
The device acts as a transparent TPL physical-layer transceiver. It converts the MCU SPI transmit stream into TPL pulse-encoded signals and converts received TPL traffic back into SPI signals. As a result, communication with devices on the TPL network is performed by sending and receiving TPL frames through the SPI interface.
You may be referring to the newer MC33665A gateway device, which does include internal registers, message queues, routing functions and a register-access protocol. The MC33665A full datasheet (available as a Secure file under NDA) therefore contains extensive register descriptions.
We have SW device drivers available for both the MC33664 and MC33665 as part of the Gen1 SDK. As for the MC33664, the CDD layer on the MCU handles tasks such as pin timing to execute a wake-up sequence, configuring and managing two independent SPI blocks on the MCU simultaneously, interrupt routing etc.
BRs, Tomas