PDI1394L41 Datasheet, PDF (29/81 Pages) NXP Semiconductors – 1394 content protection AV link layer controller

Philips Semiconductors
1394 content protection AV link layer controller
Preliminary specification
PDI1394L41
12.6 The Asynchronous Packet Interface
The PDI1394L41 provides an interface to asynchronous data packets through the registers in the host interface. The format of the
asynchronous packets is specified in the following sections.
12.6.1 Reading an Asynchronous Packet
Upon reception of a packet, the packet data is stored in the appropriate receive FIFO, either the Request or Response FIFO. The location of the
packet is indicated by either the RREQQQAV or RRSPQAV status bit being set in the Asynchronous Interrupt Acknowledge (ASYINTACK)
register. The packet is transferred out of the FIFO by successive reads of the Asynchronous Receive Request (RREQ) or Asynchronous
Receive Response (RRSP) register. The end of the packet (the last quadlet) is indicated by either the RREQQLASTQ or RRSPQLASTQ bit set
in ASYINTACK. Attempting to read the FIFO when either RREQQQAV bit or RRSPQQAV bit is set to 0 (in the Asynchronous RX/TX interrupt
acknowledge, ASYINTACK, register) will result in a queue read error.
12.6.2 Link Packet Data Formats
The data formats for transmission and reception of data are shown below. The transmit format describes the expected organization for data
presented to the link at the asynchronous transmit, physical response, or isochronous transmit FIFO interfaces.
12.6.2.1 Asynchronous Transmit Packet Formats
These sections describe the formats in which packets need to be delivered to the queues (FIFOs) for transmission. There are four basic formats
as follows:
ITEM
1
FORMAT
No-packet data
2
Quadlet packet
3
Block Packet
4
Unformatted transmit
USAGE
Quadlet read requests
Quadlet/block write responses
Quadlet write requests
Quadlet read responses
Block read requests
Block write requests
Block read responses
Lock requests
Lock responses
Asynchronous streams
Concatenated self-ID / PHY packets
TRANSACTION CODE
(tCode)
4
2
0
6
5
1
7
9
B_hex
A_hex
E_hex
Each packet format uses several fields (see names and descriptions below). More information about these fields (not the format) can be found
in the 1394 specification. Grey fields are reserved and should be set to zero values.
2000 Apr 15
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