Changes for page Trigger Howto

Last modified by sndueste on 2023/07/07 11:28
From version 12.1
edited by sndueste
on 2019/09/17 15:03
Change comment: There is no comment for this version
To version 19.1
edited by sndueste
on 2020/01/23 09:29
Change comment: There is no comment for this version

Summary

Details

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Content
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5 5  = Introduction (user panel)
6 6   =
7 7  
8 -The MTCA based triggers have a jitter in the few ps range, the delay can be shifted in 1 ns steps (over many ms), one can choose between 10 Hz triggers, frequencies locked to the pulses (e.g. 1MHz) and the actual bunch patterns. A detailed description can be found in [[x2Timer manual>>attach:x2Timer.pdf]].
8 +The MTCA based triggers have a jitter in the few ps range, the delay can be shifted in 9 ns steps, One can choose between 10 Hz triggers, Triggers connected to the (fast) FEL shutters,  frequencies locked to the pulses (e.g. 1MHz) and the actual bunch patterns. A detailed description can be found in [[x2Timer manual>>attach:x2Timer.pdf]] ([[Design Paper>>url:http://ttfinfo2.desy.de/doocs/Timing/CDRv2.2short.pdf||shape="rect"]]).
9 9  
10 -in short: the triggers are for low impedance (~~50 OHM terminated ?? ), 5V triggers with an adjustable width. The main control panel for the x2 timer has the control options for the 3 front modules (connected with a RJ45 cable - connecting to a "trigger box" with 2 trigger exits (Lemo) each) and 8 Lemo exits at the back of the crate. in the BL-beamline case these triggers are connected to the BNC (patch panel) ports at the rack.
10 +In short:
11 11  
12 -The main control can be done with a simplified user panel which can handle the timing in respect to the FEL pulses and not in respect to some (arbitrary) reference time ( Event)[[~[~[image:url:http://hasfweb.desy.de/pub/Setup/TriggerHowto/Trigger_scheme.gif~|~|alt="Trigger_scheme.gif" width="800"~]~]>>attach:Trigger_scheme.gif]]
12 +* the triggers are for low impedance (~~50 Ohm )
13 +* signal level is + 5V - otherwise 0V (in the expert panel one can also invert the signal - base line is +5 V and trigger 0V)
14 +* The trigger are send to the MTCA several ms before the first FEL pulse (3.1 ms for the "standard" trigger, 23 ms for the "early" trigger).
15 +* The timer card can delay the trigger in 9 ns  steps for more than 100 ms (an option to shift the trigger in 1 ns steps is available in the expert panel)
16 +* The shown delay in µs is in respect to the //first// FEL pulse. negative delay: trigger comes before FEL, positive : trigger comes after the FEL.
17 +* The desired delay has to be entered in the "delay to be set" field and as second step pressing the "set delay" sends the delay value to the timer card. Then the trigger delay will be changed and the "actual delay" will be updated.
18 +* The trigger can be set to only provide a trigger signal if the FEL Fast shutter is open. One has to choose which FEL shutter to use.
19 +* The trigger  width can be adjusted from 9 ns to several ms in 9 ns steps
20 +* The timer card can in addition to the 10 Hz triggers also provide frequencies which are linked to the FEL repetition rate and the actual burst pattern of the FEL. For details how to set these modes see below
21 +* At the beamlines the triggers are provided with a  BNC patch panel
13 13  
23 +The main control can be done with a simplified user panel which can handle the timing in respect to the FEL pulses (and not in respect to some arbitrary event time)
14 14  
25 +
15 15  \\
16 16  
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29 +
30 +\\
31 +
32 +\\
33 +
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37 +
17 17  = Different trigger events (starting points) =
18 18  
19 19  one can configure each channel for an individual trigger event
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84 84  
85 85  \\
86 86  
108 +\\
109 +
87 87  = Expert panels =
88 88  
89 89  \\
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102 102  
103 103  \\
104 104  
105 -\\
106 -
107 107  = Set a constant frequency to a channel =
108 108  
109 109  =
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153 153  
154 154  \\
155 155  
177 +== General FLASH frequencies: ==
178 +
156 156  \\
157 157  
181 +(% class="relative-table wrapped" style="width: 19.422%;" %)
182 +|(% class="highlight-grey" title="Hintergrundfarbe : Grau" data-highlight-colour="grey" %)(((
183 +(% style="color: rgb(0,0,0);" title="" %)**Name          
184 +**
185 +)))|(% class="highlight-grey" title="Hintergrundfarbe : Grau" data-highlight-colour="grey" %)(((
186 +(% style="color: rgb(0,0,0);" title="" %)**Frequency                
187 +**
188 +)))|(% class="highlight-grey" title="Hintergrundfarbe : Grau" data-highlight-colour="grey" %)(((
189 +(% style="color: rgb(0,0,0);" title="" %)**Divider**
190 +)))
191 +|(((
192 +1.3 GHz
193 +)))|(((
194 +1300.000000 MHz
195 +)))|(((
158 158  \\
197 +)))
198 +|(((
199 +108 MHz
200 +)))|(((
201 +108.333333 MHz
202 +)))|(((
203 +12
204 +)))
205 +|(((
206 +9 MHz
207 +)))|(((
208 +9.02777777 MHz
209 +)))|(((
210 +144
211 +)))
212 +|(((
213 +4.5 MHz
214 +)))|(((
215 +4.513888 MHz
216 +)))|(((
217 +288
218 +)))
219 +|(((
220 +1 MHz
221 +)))|(((
222 +1.003086 MHz
223 +)))|(((
224 +1296
225 +)))
159 159  
160 160  \\
161 161  
162 162  Once a clock is configured with the right frequency one can choose in the "expert panel" of the according channel the "FPGA clock" in the "input source select"  chooser.
163 163  
164 -\\
165 -
166 -\\
167 -
168 -\\
169 -
170 170  One has to set the delay to values less than the repetition rate ... (so for 1 MHz between 0 and 990 µs)  and the trigger width also less than the rep rate ...
171 171  
172 -\\
233 +This results in a continuous train of pulses with the set trigger width.
173 173  
174 -\\
175 -
176 -\\
177 -
178 -This results in a continuous train of pulses with the set trigger width :
179 -
180 180  = Creating an (own) burst trigger =
181 181  
182 182  One can use now a SECOND trigger channel which is set to a regular 10 Hz trigger  and gate the clock output to create a burst with defined start point and length,
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218 218  
219 219  \\
220 220  
221 -[[image:attach:image2019-9-17_14-52-27.png||height="248"]][[image:attach:image2019-9-17_14-52-40.png||height="250"]]
276 +[[image:attach:image2019-9-17_15-4-47.png||height="250"]][[image:attach:image2019-9-17_14-52-40.png||height="250"]]
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223 223  \\
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