Sifos Technologies PhyView PVA-3000, Reference Manual

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PVA-3000 Reference Manual
December 2, 2019 Sifos Technologies Page
126
6.1.2. Event Triggered, Multi-Port Measurements
While meter results can only be queried and retrieved on a port-by-port basis, certain PhyView Analyzer measurements
are capable of executing simultaneously on multiple test ports. This concept was discussed earlier in Section 2.2.5. A
key benefit of this feature is the ability to reduce the average time to complete measurements across multiple test ports,
especially those measurements such as
pva_echo
and
pva_xtalk
that can take considerable time to complete.
Triggered PhyView Analyzer meters include:

Link Monitor (
pva_link_mon
)

SNR (
pva_snr
)

PSD (
pva_psd
)

Bulk Return Loss (
pva_echo
)

Bulk Crosstalk (
pva_xtalk
)
Triggered measurements always involve three distinct steps:
1. INITIATE or ARM the meter on a port-by-port basis using
stat
query with
trig ext
specified
18. TRIGGER the measurement on one or more ports using
trigout
command
19. QUERY the meter on a port-by-port basis using
stat
query and retrieve results upon READY status
The time savings comes about because the time to initiate measurements (step #1) and the time to query meters (step
#3) is small relative to the time to execute the measurements. The following script demonstrates this concept using a
PSD measurement performed on every PhyView Analyzer test port in a chassis.
# Build Test Port List using pvaSlotRange global
foreach slot $pvaSlotRange {
lappend portList "$slot,1"
lappend portList "$slot,2"
}
# Configure all meters for Event Trigger & initiate PSD measurements on all
ports
pva_psd 99,99 trig ext
foreach port $portList {
pva_psd $port stat
}
# Trigger all the meters on all the Test Ports
trigout $port
# Loop waiting for the measurements to complete
# Remove ports from Test Port List when measurements are completed
while { [llength $portList] > 0 } {
foreach port $portList {
set status [
pva_psd $port stat]
# Measurement Completed or Terminated on this Test Port ?
# If so, collect result and remove current Test Port from Test Port List
if { [lindex $status 3] != "MEASURING"} {
set psdResp($port) $status
set idx [lsearch $portList $port]
set portList [lreplace $portList $idx $idx]
}
} ;
# Test Port List
} ; # Scan Loop
# View the results in PowerShell
parray psdResp