Datasheet

Fibre Channel Interface
1-8 C141-C008
1.2.2 Frame structure (refer to FC-PH, chapter 17)
A frame format is shown in Figure 1.6.
0-2048+64 (optional header)
0-5286
24
1word count
4
min6
min24byte count
fill wordsEOFCRC
PayloadFrame
Header
SOFfill words
1
4
1
4
Figure 1.6 Frame format
a) SOF; Start of frame indicates the beginning of the frame.
b) Frame Header; Used as link control, drive protocol transfer and detect error
condition.
The frame header format is listed in Table 1.1.
Table 1.1 Frame header format
word/byte 0 (bits 31 – 24) 1 (bits 23 – 16) 2 (bits 15 – 08) 3 (bits 07 – 00)
0 R_CTL D_ID
1 reserved S_ID
2 TYPE F_CTL
3 SEQ_ID DF_CTL SEQ_CNT
4 OX_ID RX_ID
5 OFFSET
*1 R_CTL; Routing Control to categorize the frame.
D_ID; Destination Identifier, N_port address to which the frame is being
sent.
S_ID; Source Identifier, N_port address originating the frame.
*2 TYPE; Data Structure Type, identifies the frame protocol.
*3 F_CTL; Frame Control information
SEQ_ID; Sequence Identifier, uniquely identifies frames in a non-
streamed sequence.
DF_CTL; Data Field Control, specifies the optional headers in the
payload. This field is not supported by the drive and used as
00h.
SEQ_CNT; Sequence Count, identifies the order of the frames.