Xycom XVME-678 Manual page 142

Appendix A - VMEbus Connector/Pin Description
Table A-I. VMEbus Signal Identification
(continued)
Signal Connector, Row: Signal Name and Description
Mnemonic
Pin Nwnber
BBSY* lB:l BUS BUSY: Open-collector driven signal generated by
the current DTB master to indicate that it is using the
bus.
BCLR* IB:2 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.
BERR*
lC:ll
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.
BGOIN*- IB:4,6,8,1O
BUS GRANT (0-3) IN: Totem-pole driven signals
BG3IN*
generated by the Arbiter or Requesters. Bus Grant In and
Out signals form a daisy-chained bus grant. The Bus
Grant In signal indicates to this board that it may become
the next bus master.
BGOOUT*- IB:5,7,9,11 BUS GRANT (0-3) OUT: Totem-pole driven signals
BG30UT* generated by Requesters. These signals indicate that a
DTB master in the daisy-chain requires access to the bus.
BRO*-BR3* 1B: 12-15 BUS REQUEST (0-3): Open-collector driven signals
generated by Requesters. These signals indicate that a
DTB master in the daisy-chain requires access to the bus.
DSO* lA:13
DATA STROBE 0: Three-state driven signal that
indicates during byte and word transfers that a data
transfer will occur on data bus lines (DOO-D07).
DS1* lA:12
DATA STROBE 1: Three-state driven signal that
indicates during byte and word transfers that a data
transfer will occur on data bus lines (DO-D 15).
A-2