DP83266VF datasheet(121/152 Pages) NSC

121 / 152 page

70 Control Information (Continued)

NON-END FRAME STATUS

0000

Last IDUD of Queue with a Page Cross

The last available location of the ICHN’s IDUD queue was written Since

there was a page cross there was more data to be written Since there was no more IDUD space the remaining data

was not written Note that this code will not be written in an IDUDMiddle so that a Zero IS field with Zero F-L tags can

be used by software as a null descriptor

0001

Page Cross

Must be an IDUDFirst or IDUDMiddle This is part of a frame that filled up the remainder of the current

page requiring a new page for remainder of the data

0010

Header End

This refers to the last IDU of the header portion of a frame

0011

Page Cross and Header End

The occurrence of a page cross and header end

NORMAL-END FRAME STATUS

0100

Intermediate

A frame ended normally and there was no breakpoint

0101

Burst Boundary

A frame ended normally and there was a breakpoint because a burst boundary was detected

0110

Threshold

The copied frame threshold counter was reached when this frame was copied and the frame ended

normally

0111

Service Opportunity

This (normal end) frame was preceeded by a token or MACRST a MAC frame was received or

there was a ring-op change Any of these events marks a burst boundary

NO SPACE COPY ABORT

1000

Insufficient Data Space

Not all the frame was copied because there was insufficient data space This code is only

written in non-HeaderInfo Sort Mode

1001

Insufficient Header Space

The frame copy was aborted because there was insufficient header space (in HeaderInfo

Sort Mode0

1010

Successful Header Copy Frame Info Not Copied

There was sufficient space to copy the header but insufficient

data space to copy info or insufficient IDU space (on ICHN2) or both No info was copied

1011

No Info Space

The frame’s header was copied When copying the data there was insufficient data andor IDU space

ERROR

1100

FIFO Overrun

The Indicate FIFO had an overrun while copying this frame This exception is caused when the memory

interface does not allow the MACSI device to empty the data FIFO as quickly as it is being filled This frame should not

be processed because data has been lost

1101

Bad Frame

This exception is caused when the incoming frame contains an invalid data length (too short or an odd

number of symbols) or an invalid Frame Check Sequence (FCS) This implies that the frame was not a valid FDDI

frame Therefore this frame should not be processed

1110

Parity Error

This exception is caused when the MACSI device detects an internal parity error at the System Interface-

Ring Engine interface (the MRFLOW bit must be set to enable parity checking) This implies a data corruption error

within the frame Therefore this frame should not be processed

1111

Internal Error

This exception is caused when the MACSI device detects an internal hardware error (eg illegal state

machine state) in the receive logic while receiving a frame This implies that the frame data may have been corrupted

Therefore this frame should not be processed In addition the MACSI device should be reset and reinitialized

FIGURE 7-5 Indicate Status Field (IS) of IDU Descriptor

121

DP83266VF Datasheet(PDF) 121 Page - National Semiconductor (TI)

DP83266VF Datasheet(HTML) 121 Page - National Semiconductor (TI)

Html Pages

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 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL