Managing Multiple-Mainframe Measurements - VXI VT1433B User Manual

VT1433B User's Guide
The Host Interface Library

Managing Multiple-mainframe Measurements

In a single mainframe measurement, the VT1433B communicates with other
VT1433Bs through the TTLTRG lines. However, when using the VXI-MXI bus
extender modules, the TTLTRG lines, which carry the group synchronization
pulse and sample clock, are extended only in one direction. This unidirectional
signal connection restricts the types of measurements that can be made in a
multiple mainframe environment.
The following types of multiple mainframe measurements cannot be performed:
q
Unequal pre-trigger delay settings between mainframes
q
Channel triggering by channels in Mainframe B
q
Lower spans or longer blocksizes in Mainframe B
q
Different digital filter settling times between VT1433B modules
Ethernet or Firewire
Embedded Controller
VT1433B VT1433B
Fail Acs Trigger Fail Acs Trigger
ExSamp Cal ExTrig ExSamp Cal ExTrig
8-CHANNEL 196 8-CHANNEL 196
kSa/s DIGITIZER kSa/s DIGITIZER
+DSP +DSP
S
l
Chan Chan
5 - 8 5 - 8
o
t
0
Chan Chan
1 - 4 1 - 4
bus bus
MXI-2
Extender
Interface
VT1433B VT1433B
Fail Acs Trigger Fail Acs Trigger
ExSamp Cal ExTrig ExSamp Cal ExTrig
8-CHANNEL 196 8-CHANNEL 196
kSa/s DIGITIZER kSa/s DIGITIZER
+DSP +DSP
Chan Chan
5 - 8 5 - 8
Chan Chan
1 - 4 1 - 4
bus bus
MXI-2 Extender Interface
Example 1: Slot 0 Controller
Figure 4-1: Multiple mainframes - two mainframes
4-14
VT1433B
VXI Mainframe A
VXI Mainframe B
VT1433B
MXI-2 VT1433B
Extender Interface
VT1433B VT1433B
Fail Acs Trigger Fail Acs Trigger
ExSamp Cal ExTrig ExSamp Cal ExTrig
8-CHANNEL 196 8-CHANNEL 196
kSa/s DIGITIZER kSa/s DIGITIZER
+DSP +DSP
Chan Chan
5 - 8 5 - 8
Chan Chan
1 - 4 1 - 4
VXI Mainframe A
bus bus
VT1433B VT1433B
Fail Acs Trigger Fail Acs Trigger
ExSamp Cal ExTrig ExSamp Cal ExTrig
8-CHANNEL 196 8-CHANNEL 196
kSa/s DIGITIZER kSa/s DIGITIZER
+DSP +DSP
Chan Chan
5 - 8 5 - 8
Chan Chan
1 - 4 1 - 4
VXI Mainframe B
bus bus
VT1433B
MXI-2 Extender Interface
Example 2: MXI-2 Daisy Chain