PDI1394L40BE,551 NXP Semiconductors, PDI1394L40BE,551 Datasheet - Page 29

• Manufacturer Part Number: PDI1394L40BE,551
• Manufacturer: NXP Semiconductors

Specifications of PDI1394L40BE,551

• Lead Free Status / Rohs Status: Compliant

Philips Semiconductors
12.6 The Asynchronous Packet Interface
The PDI1394L40 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:
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 Dec 15
1394 enhanced AV link layer controller
ITEM
1
1
2
3
4
No packet data
No-packet data
Quadlet packet
Block Packet
Unformatted transmit
FORMAT
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
25
USAGE
TRANSACTION CODE
PDI1394L40
(tCode)
Preliminary specification
B
A
E
hex
hex
hex
4
2
0
6
5
1
7
9