Datasheet
4–16
4.9 Receive Self-ID
The format of the receive self-ID packet is shown in Figure 4–23 and described in Table 4–11. The first
quadlet is the packet token with the special code of Eh. The quadlets that follow are a concatenation of all
received self-ID packets. See paragraph 4.3.4.1 of the IEEE 1394-1995 standard for additional information
about self-ID packets.
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
spd errCode
Self-ID Packet Data
Write Count1
1110
0
tcode=E
Reserved
NOTES: A. Bit 11 (PacCom) = 1
B. Speed should be S100 (spd=00).
Figure 4–23. Receive Self-ID Packet Format(RxSID bit = 1)
Table 4–11. Received Self-ID Packet Functions
FIELD NAME DESCRIPTION
spd The spd field indicates the speed at which the current packet is to be sent (00 = 100 Mbits/s,
01 = 200 Mbits/s, and 10 = 400 Mbits/s, and 11 is undefined).
WriteCount WriteCount indicates the number of data quadlets in the packet.
errCode The errCode field indicates whether the current packet has been received correctly. The
possibilities are complete, DataErr, or CRCErr, and have the same encoding as the
corresponding acknowledge codes (See Table 6–13 of the IEEE 1394
-1995 standard).
Self-ID packet data This field contains a concatenation of all the self-ID packets received (see self-ID packet
descriptions below)
The cable PHY sends one to three self-ID packets at the base rate (100 Mbits/s) during the self-ID phase
of arbitration or in response to a ping packet. The number of self-ID packets sent depends on the number
of PHY ports. Figures 4–24, 4–25, and 4–26 show the format of the cable PHY self-ID packets. Table 4–12
describes the details of these packets.
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
gap_cnt
Logical inverse of first quadlet
sp
phy_ID10 0L rsv c pwr p0 p1 p2 i m
Packet
Identifier
Figure 4–24. PHY Self-ID Packet #0 Format
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
Logical inverse of first quadlet
phy_ID10 1 n(0) rsv p8 p9 p10 mp3 p4 p5 p6 p7
Packet
Identifier
Figure 4–25. PHY Self-ID Packet #1 Format