HP 81101A Quick Start Manual page 45

Furthermore, you can specify the pulse and trigger sources.
The following table provides a list of possible parameter combinations.
The rows refer to the numbers in the figure.
Trigger Mode Continuous
Pulse Mode Pulses
Pulse Type Single/Double
Length
Period Source internal Osc.
internal PLL
CLK-IN
Arming Source
Trigger Out
Strobe Out not used
The pulse period source can be selected from internal oscillator, internal
PLL, and external CLK-IN:
• If you have to trigger after an external event, use the startable
oscillator (internal Osc.), which starts on the external signal with a
fixed latency.
• If you do not have to trigger but need a high accuracy frequency, then
use the internal PLL clock generation circuitry.
• For even more accuracy, you can use the external CLK-IN.
In triggered/gated mode the internal PLL can be used as an arming
source. However, the internal PLL cannot be used as pulse and arming
source at the same time.
The following sections explain the individual mode combinations in
more detail. For each combination of trigger mode and pulse mode,
typical timing diagrams are provided, showing single and double pulses.
Triggered
Burst Pulses
Single/Double
2–65536
MAN key
Ext. Input
marks each pulse period generated
↑
not used
on 1st
↓
on last
The Mode/Trigger Screen
Gated
Burst Pulses
Single/Double
2–65536
internal Osc. internal Osc.
internal PLL internal PLL
CLK-IN CLK-IN
MAN key MAN key
Ext. Input Ext. Input
PLL
↑
not used
on1st
↓
on last
Using the HP 81101A
Ext. Width
Burst
2–65536
MAN key
Ext. Input
↑
not used
on 1st
↓
on last
45