505 Pulse Generator Operating Manual Berkeley Nucleonics Corporation 2955 Kerner Blvd. San Rafael, CA 94901-5418 (415)453-9955 phone (415)453-9956 fax www.berkeleynucleonics.
Contents 1 Introduction................................................................ 1 Technical Support ..............................................................................................2 Warranty .............................................................................................................2 Package Contents ..............................................................................................2 Safety Issues .............................................................
Setting Pulse Gate Control ..........................................................................................................16 Setting the System Internal Rate Generator ..........................................................................16 Setting System Mode of Operation ............................................................................................16 Enabling System Trigger or Gate ...............................................................................................
SCPI Query Format .......................................................................................................................31 SCPI Keyword Separator ...............................................................................32 SCPI Optional Keywords ................................................................................32 SCPI Specific and Implied Channel .............................................................32 SCPI Parameter Types .........................................
1 Introduction 1
Introduction This manual is a reference designed to familiarize you with the Berkeley Nucleonics 505 pulse generator and is arranged so that you can easily find the information you’re looking for. Generally, each topic has its own section, and no section assumes that you’ve read anything else in the manual.
Safety Issues Normal use of test equipment presents a certain amount of danger from electrical shock because testing must be performed where exposed voltage is present. An electrical shock causing 10 milliamps of current to pass through the heart will stop most human heartbeats. Voltage as low as 35 VDC or RMS AC should be considered dangerous and hazardous since it can produce a lethal current under certain conditions.
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2 Front Panel Overview 5
Front Panel Overview BNC 505 Front Panels Display Layout and Indicators A 2 line x 16 character, backlit LCD display module displays all system parameters and status information. The status information is located in the upper-right corner of the display. There are two enunciators: • Rotating Pie • Vertical Arrow Indicates the unit is actively generating pulses, or armed and waiting for an external trigger. Indicates the function key has been pressed.
• Rotary Knob • Channel Outputs • External Input The Rotary Knob may be used to adjust the current parameter as an alternate to the ARROW keypad. The step size is controlled by the position of the cursor. However, turning the knob faster will increase the step size. Pushing the knob performs the same function as pushing the NEXT key, selecting the next parameter in the currently displayed menu. The pulse generator output is available from BNC connectors on the front panel.
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3 Pulse Concepts and Pulse Generator Operations 9
Pulse Concepts and Pulse Generator Operation Counter Architecture Overview Arm Gate * Start To Internal System Tim er and S ystem Mode Generator Internal To Pulse RUN Command External Input Start Gate ** Arm Channel Timers and Channel Mode Generators Output MUX Output Pulses * Start source is: RUN button in Internal Modes in External trigger modes. * Start source is:External RUN buttoninput in Internal Modes External i nput i n E xternal trigger modes ** Channels are armed by the RUN button.
Channel Timer Functions The Channel Timer functions as a non-retriggerable, delayed, one shot pulse generator. This means that the timer will only generate one delayed pulse for every start pulse received. Once the channel timer has started counting, additional start pulses will be ignored until the pulse has been completed (nonretriggerable). The start pulse for each channel is provided by the internal To pulse generated by the Internal System Timer.
Numeric Input Mode When the current item is numeric, the system enters the Numeric Input Mode. In this mode data may be edited in one of two ways. Using the arrow keypad, the Left and Right arrow keys are used to select a digit to edit. The selected digit blinks to identify itself as the active digit. The Up and Down arrow keys are then used to increment or decrement this digit.
Configuration # The configuration # specifies the location to store the current system configuration. Numbers range from 1 to n, where "n" is the number of stored configurations. *NOTE: The number of storage locations is model dependent; see the specifications for your model. You cannot store to the zero location, as that contains the factory default values. • From the Store menu, press the setup button (function + setup).
Enabling External Gate Control • EXTin Selects external input usage for controlling To: disabled, edge triggered or level gated. *NOTE: When the gate disables the System Timer, the timer is reset. The gate edge, to enable the timer, will restart the System Timer, which synchronizes the To pulse to the gate and minimizes jitter relative to the gate. The trigger threshold applies to all uses, channel and system, of the trigger/gate input.
Setting Key and Knob Volume • Key Volume • Knob Volume Sets the key click volume. Sets the parameter adjustment knob click volume. Setting Pulse Timing Parameters Within the CHANNEL menu, set the delay until the start of a pulse and the pulsewidth: • Delay • Width Sets the delay from the sync source to the start of the pulse. Sets the width of the active portion of the pulse.
This allows other channels to be run continuously without interruption while generating individual pulses or a burst of pulses on the single shot or burst mode channels. Setting Pulse Gate Control Enables the use of the external input to gate the channel output (within the CHANNEL menu): • Gate Enables/disables the channel gating using the external trigger. Enables the gate by selecting either active high or active low. This function is independent of any other use of the trigger input.
• AutoStart Disable or enable the autostart feature.
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4 505 Menus 19
505 Menus 505 Menu Structure CHANNEL Menu Channel Sync Delay Width Mode #/Burst On Cycle Off Cycle Wait Polarity Amplitude Gate MODE Menu Period Mode #/Burst On Cycle Off Cycle TRIG/GATE Menu EXTin Level Gate Edge 20 Disable/enable channel output. Select sync source. Sets delay from sync source until pulse is started. Sets width of active portion of pulse. Selects the channel timer mode. Sets the number of pulses in the burst mode. Sets the number of pulses in the duty cycle mode.
SYSTEM Menu Baud Rate Comm Echo GPIB Addr Key Vol Key Rate Knob Vol Autostart Mark Selects the RS232 baud rate. Enables RS232 input echo. Sets the GPIB address. Sets the key beep volume, 0 is off. Sets the key repeat rate. Sets the knob beep volume. Enables pulse output on startup. Selects the decimal point character. SETUP Menu Store# Recall# Store the current configuration. Reloads the requested configuration.
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5 Operating the 505 23
Operating the 505 Quick Start - Normal Internal Rate Generator Operation The 505 has a powerful set of functions providing a number of modes of operation. Most of these functions can be ignored if all one wants to do is generate a simple continuous stream of pules. Starting from the default settings, which can be loaded by recalling configuration 0, the following parameters need to be set: Pulse Width, Delay Enter the CHANNEL menu by pressing the FUNCTION key and then the CHANNEL key.
Edge Press the NEXT key until the Edge parameter is displayed. Set the instrument to trigger off the rising edge or falling edge as desired. Pulse Width, Delay Enter the CHANNEL menu by pressing the FUNCTION key and then the CHANNEL key. Enter the required pulse width and delay. Repeat for each output channel. Start Press the RUN key to start/arm the instrument. The 505 will now generate a pulse for every valid trigger. Stop Press the STOP key to stop/disarm the instrument (i.e.
Pressing the RUN key will now generate a stream of “n” pulses, at a rate specified by the period parameter. To Use Duty Cycle Mode To generate a stream of pulses which oscillates on for “n” pulses and off for “m” pulses - within the MODE menu set the following parameters: Mode DC On DC Off Period Select Duty Cycle for the system mode. Select the number of “on” pulses. Select the number of “off” pulses. Select the desired period.
To Use Channel Burst Mode Function The Burst mode generates a burst of pulses every time the RUN key is pressed. If the unit is in the active, (i.e. channels which are set to the Normal mode are producing pulses), pressing the RUN key will reset the Burst counters and generate a new set of pulses in sync with the other channels running in the Normal mode. To use the Burst mode - within the CHANNEL menu, set the following parameters: Channel Delay Width Mode #/Burst Select Enable to enable channel output.
To Generate a Pulse on Every Trigger Input To generate a pulse on every external trigger received, set the following parameters: - within the Mode menu: Mode Select the Single Shot mode. - within the TRIG/GATE menu: EXTin Select Triggered mode. Level Set the trigger threshold level. Edge Select which edge, rising or falling, to trigger on. Pressing the RUN key will arm the unit. Once the unit is armed, it will generate a To pulse for every external trigger received.
- within the TRIG/GATE menu: EXTin Select Triggered mode. Level Set the trigger threshold level. Edge Select which edge, rising or falling, to trigger on. Pressing the RUN key will arm the unit. Once the unit is armed, it will begin generating pulses after an external trigger is received. Triggers that occur after the pulses start are ignored. Pressing the STOP key will disarm the unit. To use the External Gate to Control the System The external trigger may be used to control the output of the unit.
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6 Programming the 505 31
Programming the 505 Talking to the Pulse Generator The 505 comes standard with an RS232 serial interface and an optional GPIB interface. All menu settings can be set and retrieved over the computer interface using a simple command language. The command set is structured to be consistent with the Standard Commands for Programmable Instruments (SCPI). Although due to the high number of special features found in the 505, many of the commands are not included in the specification.
Programming Command Types and Format The 505 Pulse Generators use two types of programming commands: IEEE 488.2 Common Commands and Standard Commands for Programmable Instruments (SCPI). The format is the same for both the RS232 interface and the optional IEEE 488 interface. Hyperterminal (in Windows) or any other generic terminal program may be used to interactively test the commands using the RS232 interface. The format of each type is described in the following paragraphs. IEEE 488.
Any parameter may be queried by sending the command with a question mark appended. For example: :PULSE1:STATE? Will return: 1 Will return: :PULSE1:WIDT? 0.000120000 Will return: :PULSE1:POL? NORM SCPI Keyword Separator A colon (:) must always separates one keyword from the next lower-level keyword. A space must be used to separate the keyword header from the first parameter.
Represents a single binary condition that is either true or false. True is represented by a 1 or ON; false is represented by a 0 or OFF. Queries return 1 or 0. Selects from a finite number of predefined strings. Error Codes The unit responds to all commands with either: ok or ?n Where "n" is one of the following error codes: 1 2 3 4 5 6 7 Incorrect prefix, i.e. no colon or * to start command. Missing command keyword. Invalid command keyword.
To arm the instrument use either of the following commands: :PULSE0:STATE ON :INST:STATE ON arms the instrument alternate form A software generated external trigger can be generated by using the following command: *TRG generates a software external trigger 505 SCPI Command Summary K eyword Parameter Std/ N ew C omments :IN STrument Std Subsystem. Supports treating each channel as a logical instrument. :C ATalog? Std Q uery only.
505 SCPI Command Summary K eyword Parameter [:PULSe] [0] Std/ N ew C omments Std Subsystem. C ontains commands to control the output pulse generation. C ommands without suffix refer to the currently selected logical instrument. See IN STrument subsystem. :STATe Std Enables / Disables the output for all channels. C ommand is the same as pressing the RUN or STO P button. :PERiod Std Sets the To period.
505 SCPI Command Summary K eyword Parameter :PULSe [1 / 2 / n] Std/ N ew C omments Std Subsystem. C ontains commands to control the output pulse generation. Valid suffix range depends on the number of channels (C HA = 1, C hB = 2, etc). C ommand without suffix refers to the currently selected logical instrument. See IN STrument subsystem. Enables/Disables the output pulse for selected channel. :STATe Std :WIDTh Std Sets the width or duration of the output pulse.
505 SCPI Command Summary K eyword Parameter :SYSTem Std/ N ew Comments Std Q uery only. Returns the state of the machine: returns ACTIVE if the machine is armed and/or N ew generating pulses or IDLE if the machine has been disarmed. :STATe :BEEPer Std Subsystem. Controls the audible beeper. :STATe Std Enables/disables the beeper. :VO Lume Std Sets the volume of the beeper. Range is 0 to 100, where 0 is off and 100 is maximum volume. Std Subsystem.
IEEE 488.2 Common Commands Mnemonic Command N ame Parameters Comments Identification Q uery Q ueries the Pulse Generator Identification. The ID will be in the following format: model#- option#- version# *RCL Recall Command Restores the state of the Pulse Generator from a copy stored in local nonvolatile memory (0 through 10 are valid memory blocks). *RST Reset Command Resets the Pulse Generator to the default state.
Appendix 41
Appendix A - Specifications 505 Specifications DELAYS CHANNELS MODES DELAY PULSEWIDTH RESOLUTION ACCURACY TIMEBASE RMS Jitter BURST MODE EXTERNAL TRIG / GATE RATE THRESHOLD INPUT RANGE TRIGGER SLOPE RMS JITTER INSERTION DELAY 2, 4 or 8 independent outputs, with digitally con trolled delay and pulsewidth Normal, Single, Shot, Burst, Duty Cycle 0 to 999.9999999 sec 100 ns to 999.9999999 sec 10 ns 10 ns + .
COMPUTER INTERFACE RS232 4800, 9600, 19200, 38400 Baud. All instrument functions and settings may be con trolled over the interface bus. GENERAL STORAGE DIMENSIONS WEIGHT POWER Storage for 6 complete configurations may be stored and recalled from the front panel or the computer interface. 7.
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