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Related Manuals for LabSmith LC880
Summary of Contents for LabSmith LC880
- Page 1 LC880 Experiment Controller User Guide Documentation for the LC880™ Controller and Trigger™ Control Software v. 5.0 Trigger software ©1996--2002 LabSmith. This manual ©2002 LabSmith. No part of this document may be reproduced or distributed without the consent of LabSmith.
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Page 3: Table Of Contents
INTRODUCTION Parts List Specifications Basic Functions How You’ ll Use the LC880 Installing Trigger Software Setting Up the LC880 Getting Help OVERVIEW OF LC880 CONTROLS Back Panel Inputs and Outputs Front Panel Controls TRIGGER SOFTWARE INTERFACE Main Screen General Settings... - Page 4 RUNNING EXPERIMENTS Storing and Recalling Experiment Files Front Panel Controls and Indicators Channel LEDs ALL Channel LED Selecting a Channel from the Front Panel Performing a Front Panel Function Enable/Disable ALL Enable/Disable Channel Trigger a Channel Reset Store/Recall Settings Profiles...
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Page 5: Introduction
The timing properties and logic that you set up in Trigger can be transferred and stored in the memory of the LC880. You can store up to 64 variations of these properties in settings profiles in the LC880. You can then switch between... -
Page 6: How You' Ll Use The Lc880
6. Select the port to which the LC880 is connected. The LC880 will automatically detect the baud rate, which is typically set to 38400. If the RS232 cable running to your LC880 is greater than 30m long, you may need to... -
Page 7: Getting Help
Getting Help This guide is your main source for information on operating the LC880 and Trigger software. The guide is also ® ® available in an Adobe Acrobat Portable Document Format (pdf) file for electronic viewing. While running Trigger, press F1 to view this document on-line. Or, press SHIFT-F1, then select a button or menu option to view help topics for a particular feature. -
Page 8: Overview Of Lc880 Controls
Indicators and controls on the LC880 front panel will help you run your experiments. You’ ll learn all about these functions in the Experimenting section later. For now, we’ ll give you a short tour of the inputs, outputs and controls so you can work with the unit while you learn to use the Trigger software. -
Page 9: Front Panel Controls
Power LED The LC880 front panel controls begin with the Power button and Power LED in the upper left corner. When you first press the Power button, the LED will flash green and red while the system runs its initial diagnostics. It will then glow a steady color . -
Page 10: Trigger Software Interface
TRIGGER SOFTWARE INTERFACE Trigger has been designed exclusively for setup and control of the LC880. You’ ll use Trigger to set the timing properties and logic for each of the eight channels and to set up overall properties for the experiment. -
Page 11: General Settings
Each of the tabs of the General Settings screen includes buttons that let you “disable” and “enable” all inputs and outputs to the LC880. With I/O disabled, input signals are ignored. Each output will be held at either a logic low or logic high, depending upon its channel properties. -
Page 12: Time Base Settings
Time base settings Each pair of channels of the LC880 can independently utilize one of four different time bases so you can control and measure events that occur a few nanoseconds apart, or a few hundred seconds apart. In “100” MHz time base mode (the default) , the LC880 aligns signals to an internal 100 MHz clock, for timing resolution of 10 ns. -
Page 13: Channel Properties
CHANNEL PROPERTIES Channel Properties Screen Each channel has a Settings screen in which you’ ll select the timing mode, set the timing properties, and establish the logic that will determine when the channel will trigger. To open the Settings screen for a channel, select the channel from the Channel menu, or click a channel button (A – H) on the Main screen. -
Page 14: Quiescent States
The method for setting the quiescent state depends on the timing mode. Most modes include an “Invert Output” option which sets the output normally High. Timing Modes In this section we’ ll begin to use the various LC880 timing modes. Each channel can be configured to operate in one of eight modes: Fixed output... -
Page 15: Apply" Versus "Program All Channels
“Apply.” Clicking the “OK” button will also have the same effect. Logic settings are sent and saved in the LC880, but any changes are not implemented on the LC880 until you click “Set All Channels” button on the Main screen or choose Program>Program All Channels. -
Page 16: Passive Mode (Output = Input)
On the “Properties” tab of Channel A, choose “Fixed Output” from the pop-up. Choose “Low” or “High” as the output state, then click “Apply” to save the settings. At Output A, the signal will remain a steady TTL logic low or high, depending on your selection. -
Page 17: Clocked Pulse Stream Mode
As mentioned earlier, the LC880 can operate in two clock modes: hi-resolution and low-resolution (see General Settings: Clock). In hi-res mode, the clock pulse and duration can range from 0.64 µs to 52.4 ms in increments of 160 ns. -
Page 18: Delayed Pulse After Trigger Mode
To try Clock mode: 1. On the General Settings screen, select “100/64” (low-resolution mode) for Channels A and B. 2. On Channel A’ s Properties tab, choose “Clock” as the mode, select an “on” duration of 100 ms and an “off” duration of 500 ms. - Page 19 Limits the number of retriggers allowed between resets (between 0 and 2,147,483,647). To allow a channel to be triggered again after reaching the limit, press the “Reset” button on the LC880 or choose Program>Reset Channels in Trigger. Trigger on rising input Sets the channel to be edge triggered.
- Page 20 Alert host computer Sends a “ping” to the PC upon completion of the trigger cycle. following trigger Sweep To facilitate time-delay scanning experiments, the delay of the pulse relative to the trigger can be “swept” or incremented by a specified value each time the channel is triggered. The sweep value must be positive. The increment resolution is 5 ns.
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Page 21: Validated Trigger Input Mode (Noise Suppression)
The channel LED remains red, indicating it is not ready to trigger. Push the button again. You’ ll see that you cannot retrigger the channel. Click the “Reset” button on the LC880— the LED glows green and you can once again trigger the channel. - Page 22 Limits the number of retriggers allowed between resets (between 0 and 2,147,483,647). To allow a channel to be triggered again after reaching the limit, press the “Reset” button on the LC880 or choose Program>Reset Channels in Trigger. Trigger on input high Allows the channel to be repeatedly triggered while an input is high.
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Page 23: Counter/Timer Mode
(e.g., >1000 measurements per second). When you first run the LC880, channels that are configured as counters NOTE: are initially disabled and must be enabled either by clicking the “Enable” button on the channel’... - Page 24 6. Lastly, click “Send Logic” on the Main screen to update the new logic for Channel A. The time difference measurements should now appear, in rapid succession, in the “Last Measured Period” box on Channel A. The LC880 may be measuring time differences faster than it can display NOTE: them all on the monitor! Now, check “Hold measurement.”...
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Page 25: Dynamically-Delayed Pulse Mode
Dynamically-Delayed Pulse Mode The dynamic delay is the LC880’ s piece de resistance. First, it measures the time difference between two pulses, like a counter. Next, it scales that difference by a user-defined factor. It subtracts an offset value, waits the duration of the dynamically calculated delay, then sends a pulse to the channel output. - Page 26 Limits the number of retriggers allowed between resets (between 0 and 2,147,483,647). To allow a channel to be triggered again after reaching the limit, press the “Reset” button on the LC880 or choose Program>Reset Channels in Trigger. Trigger on rising input Sets the channel to be edge triggered.
- Page 27 7. Since you’ ve made changes to multiple channels, go to the Main screen and click the “Set All Channels” button.. All of your changes will now be stored in the LC880. Now the test is ready. Depress and hold the trigger button. Output A will transition high, causing the delayed trigger in Channel B to begin its count.
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Page 28: Toggled Output Mode
Toggled Output Mode This mode toggles its output state upon every input pulse. It functions like a flip-flop and is useful for a variety of logical and control purposes. The minimum input-pulse state duration is 10 ns and the edge-to-toggle delay is < 20 The only user settings for this mode are the initial state, which may be either low or high. - Page 29 To set up a channel’ s logic, open the channel’ s Settings screen, then click the “Logic” tab. Type the logical statement in the large white box. A typical logical statement may read: inB = not in2; This statement means, “Trigger Channel B when the signal at input 2 turns low (drops below 0.2 Volts).” Once triggered, the channel will function according to its timing properties (see below).
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Page 30: Predefined Variables
Many symbols can be written in “shorthand” to speed up the process of writing logic. For example, “not in1” can be written “!in1”. Refer to the list below for other shorthand characters. The following symbols can be used in logical statements: Symbol Shorthand &... -
Page 31: Global Variables
When you have completed a logical statement, click “Apply” or “OK.” Trigger will check the statement for syntactical and logical errors and will report any mistakes to you by line number. Sending Logic When you alter channel logic you must transfer the changes to the LC880 to implement it. - Page 32 While the logic is transferring, the Power LED on the LC880 will turn red. Logic transferring typically takes only a second, though it may take slightly longer for complex programs. After the transfer, the logic settings reside in the LC880, even if you turn the unit off or disconnect it from the PC.
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Page 33: Running Experiments
To reuse an experiment file, choose File>Open, and locate the file. When you click “OK,” the file’ s settings will appear in Trigger. Click “Send Properties,” then click “Send Logic” to download the settings to the LC880. You can also choose “Program All Channels” and “Program Logic” from the Program menu. -
Page 34: Selecting A Channel From The Front Panel
Selecting a Channel from the Front Panel Each front panel function requires that you select a channel (or ALL channels) and a function. To select a channel, click the channel button. The channel LED will glow brightly, as will the available Function buttons. -
Page 35: Enable/Disable All
Occasionally you’ ll need to abort an experiment in progress, due to equipment problems, etc. The quickest way to shut down an experiment is to disable the inputs and outputs of the LC880. To do so, click the “Disable” button, then click a particular channel button, or the ALL channels button. -
Page 36: Store/Recall Settings Profiles
You can recover these settings even after the unit has been turned off or disconnected. The most recently used setting is automatically loaded when the LC880 is powered up. If you attempt to recall an invalid setting, the power LED flashes red and the system retains its previous setting. - Page 37 Windows 95, 98, Me, NT, 2000 and XP are registered trademarks of Microsoft Corporation. Adobe and Acrobat are registered trademarks of Adobe Systems, Inc. Trigger software ©1996–2002 LabSmith. This manual ©2002 LabSmith. No part of this document may be reproduced or distributed without the consent of LabSmith.