Packetized Transfers
Transactions are constructed out of combinations of various packet types and carry the commands, address, and data associated with each transaction. Packets are organized in multiples of 4-byte blocks. If the link uses data paths that are narrower than 32 bits, successive bit-times are added to complete the packet transfer on an aligned 4-byte boundary. The primary packet types include:
Control Packets — used to manage various HT features, initiate transactions, and respond to transactions
Data packets — that carry the payload associated with a control packet (maximum payload is 64 bytes).
As illustrated in Figure 2-13, the control (CTL) signal differentiates control packets from data packets on the bus.
Figure 2-13. Distinguishing ...
Get HyperTransport™ System Architecture now with the O’Reilly learning platform.
O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.
