Vmetro VBAT-PB, Руководство пользователя

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9 VBAT-PB VME bus anomaly trigger
Violation descriptions
The different violations that can be detected by the VBAT-PB are described
below. The location of the individual trigger output for each violation (TP1-
TP40) is also given in the table. (Refer fig. 2 and silk screen on the VBAT-PB
module for location of the test points).
An *H* or *F* is used some places to indicate hidden or falsely detected
violations.
*H*
*F*
Violation
Hidden violations, denotes an error which may NOT be detected if a bus grant
or IACKIN/IACKOUT daisy chain, is interrupted before the appropriate BGx*
or IACKOUT* signal could reach the VBAT. To remedy this, the VBAT-PB
should, where possible, be located to the left of an active master which could
block the daisy chain.
Falsely detected, denotes an error which may FALSELY be detected, even
though no error condition actually exists, if a bus grant daisy chain is
interrupted before the appropriate BGx* signal could reach the VBAT. To
prevent this [false] error indication, the VBAT-PB should, where possible, be
located to the left of a master which could block the daisy chain. If not
possible, and if momentary low-going trigger cannot be tolerated, it may be
necessary to mask off these violations (See "Ignore violations" above.)
Test
point
Description False/
Hidden
D(7:0)
UNSTB
D(15:8)
UNSTB
D(23:16)
UNSTB
D(31:24)
UNSTB
A(7:1)
UNSTB
TP1
TP2
TP3
TP4
TP5
Data lines DO-D7 change during an interval when they
should be stable.
Data lines D8-D15 change during an interval when they
should be stable.
Data lines D16-D23 change during an interval when they
should be stable.
Data lines D24-D31 change during an interval when they
should be stable.
Address lines AO-A7 change during an interval when they
should be stable.
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