Curtiss-Wright FibreXtreme SL240, Hardware Reference Manual

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REGISTER SET
Receive Chain Length/Flags (CLENFLGS0) – Offset 0x78
Field Description Access
Reset
Value
23 to 0 Length of buffer in 32-bit words. R/W 0
24 End Chain – Write ‘1’ to say this is the last chain entry.
Write ‘0’ if it is not. R/W 0
25 Reserved. None 0
27 to 26 Data Swapping – “00” for straight, “01” to swap bytes,
“10” to swap 32-bit words, “11” to swap 32-bit words
and bytes.
R/W 0
28 Reserved. None 0
29 Interrupt – Write ‘1’ to interrupt on transfer complete,
Write ‘0’ otherwise. R/W 0
30 Go – A ‘1’ starts this transaction, A ‘0’ stops it. If it is a
chained transaction, the first action is to fetch the chain
entry. R/W 0
31
Done – A ‘1’ indicates this channel is currently idle. A
‘0’ indicates a DMA is in progress.
R 0
Receive Next Chain Entry (CNEXT0) – Offset 0x7C
Field Description Access Reset
Value
3 to 0 Reserved (Lower four bits of PCI address must be
zero). None 0
31 to 4 PMC address for the next chain entry. R/W 0
Copyright 2006 B-16 FibreXtreme Hardware Reference Manual