PDI1394L11 Datasheet, PDF (12/46 Pages) NXP Semiconductors – 1394 AV link layer controller

Philips Semiconductors
1394 AV link layer controller
Product specification
PDI1394L11
12.5 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.
12.5.1 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 FORMAT
USAGE
TRANSACTION
CODE
(tCode)
Quadlet read
4
requests
1 No-packet data
Quadlet/block write
2
responses
Qaudlet write
0
requests
2 Quadlet packet Quadlet read
6
responses
Block read requests
5
Block write requests
1
Block read
7
3 Block Packet ^responses
Lock requests
9
4
Unformatted
transmit
Lock responses
Concatenated self-ID
/ PHY packets
B_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.
12.5.1.1 No-data Transmit
The no-data transmit formats are shown in Figures 4 and 5. The first quadlet contains packet control information. The second and third quadlets
contain 16-bit destination ID and either the 48-bit, quadlet aligned destination offset (for requests) or the response code (for responses).
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
0 spd
tLabel
rt
tCode 0000
destinationID
destinationOffsetHigh
destinationOffsetLow
Figure 4. Quadlet Read Request Transmit Format
SV00250
1997 Oct 21
12