Xycom XVME 200 Manual page 43

XVME-200/290 Manual
December, 1987
Table A-l. VMEbus Signal Identification (cont'd)
Connector
Signal and
Pin Number
Mnemonic
A0l-A23 A:24-30
1
lC:15-30
A24-A31
2B:4-11
BBSY* 1B:l
lB:2
BCLR*
BERR* 1C:ll
1 B:4,6,
BGOIN*-
8,l0
BG3IN*
BG0OUT*-
1 B:5,7,
BG3OUT*
9,ll
Signal Name and Description
ADDRESS BUS (bits l-23): Three-state driven address
lines that specify a memory address.
ADDRESS BUS (bits 24-31): Three-state driven bus
expansion address lines.
BUS BUSY: Open-collector driven signal generated by
the current DTB master to indicate that it is using the
bus.
BUS CLEAR: Totem-pole driven signal generated by the
bus arbitrator to request release by the DTB master if
a higher level is requesting the bus.
BUS ERROR: Open-collector driven signal generated by
a slave. It indicates that an unrecoverable error has
occurred and the bus cycle must be aborted.
BUS GRANT (0-3) IN: Totem-pole driven signals
generated by the Arbiter or Requesters. Bus Grant In
and Out signals form a daisy-chained bus grant.
Bus Grant In signal indicates to this board that it may
become the next bus master.
BUS GRANT (0-3) OUT: Totem-pole driven signals
generated by Requesters. These signals indicate
DTB master in the daisy-chain requires access to the
bus.
A-2
The
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