Specifications

Before Installation
Installing the VXIbus Backplane Jumpers
The VXIbus contains several daisy-chained control signals. Most VXIbus
backplanes contain jumpers or DIP switches for these control signals to allow
systems to operate across empty slots. Failing to install these jumpers properly is a
common source of problems when integrating a new VXIbus system. In this manual,
these jumpers or DIP switches will be referred to as jumpers.
22
The VXIbus specification provides 4 bus grant signals (
BG0 - BG3) and 1 interrupt
acknowledge signal (
IACK) via daisy-chain lines. Per the VXIbus specifications, all
boards are required to correctly handle these signals. All slots that do not have a
board plugged into the backplane (i.e. empty slots and slots occupied by some multi-
slot instruments), need to be jumpered to allow the signals to pass through to other
instruments in the system.
xxxOUT
xxxIN
xxxOUT
xxxIN
xxxOUT
xxxIN
VXIbus Slots
xxxIN
xxxOUT
Figure 2. Daisy-Chain Signal Concept.
The Slot-0 controller board initiates each daisy-chain signal. Each VXIbus slot to the
right of the Slot-0 controller must pass through each of the daisy-chain signals. For
each VXIbus slot,
xxxIn pin must be connected to its corresponding xxxOut pin
(e.g.
BG0In to BG0Out, BG1In to BG1Out,...,IackIn to IackOut) either
through the board in that slot or by jumpers.
Some boards correctly pass all of these signals, some boards handle some of these
signals and not others, and some boards (typically "dumb" slave boards) may not
Page 7
Artisan Technology Group - Quality Instrumentation ... Guaranteed | (888) 88-SOURCE | www.artisantg.com