E STRUCTURA DE A UTOPROTECCIÓN

8. Pressing the Show Map soft key displays a list of acquired data numbers and the time at acquisition end.

9. Turn the jog shuttle to select the number of the waveform to be displayed and press SELECT. The waveform of the selected number is displayed.

Explanation

The acquisition memory retains waveform records generated by the most recent triggers. If a trigger is activated beyond the number of triggers that can be held, the oldest waveform data are cleared. Once the history becomes full, each new trigger causes loss of the oldest waveform record in the memory.

Selected Record Number

You can display any waveform from the history by entering its record number. The newest (current) waveform is Record 0, the immediately previous waveform is Record -1, and so on. The range for Selected Record No. is therefore [0 to - (retained waveforms - 1)]. The number of retained waveforms (triggers) depends on the record length, as follows. Record Length DL1620/DL1640 DL1640L 1 kword 1 to 4000 (2000) 1 to 16000 (8000) 10 kwords 1 to 500 (250) 1 to 2000 (1000) 100 kwords 1 to 50 (25) 1 to 200 (100) 1 Mword 1 to 4 (2) 1 to 20 (10) 4 Mwords – 1 to 4 (2) 8 Mwords 1 – 10 Mwords – 1 32 Mwords – 1

* For each count of the trigger, only the displayed waveform is preserved; past waveform data is not preserved.

* Values in parentheses above are only available if the high-resolution mode is ON.

Display

• Set to One to display the selected record only.

Select the waveform to be displayed using Select Record from the specified range between Start Rec and End Rec.

• Set to All to generate overlapped display of all history records from the Start Rec No. to the End Rec No. The waveform corresponding to the Selected Record No. will appear brighter than the other waveforms.

Show Map (A List of Time Stamps)

You can list the number of the waveform data stored in the acquisition memory and the time at acquisition end.

One screen displays 75 data points of information. You can scroll through the data by using the jog shuttle.

Precautions and Restrictions

• You cannot use the history function while the acquisition mode is set to Average. (Displayed history records will be meaningless.)

• The history memory function cannot be used in repetitive sampling mode.

• If you suspend waveform acquisition before the current record has been fully read, the record will not be recorded in the history.

• You cannot use the history function while roll mode is selected.

• History records are not lost when waveform acquisition is stopped and then restarted, provided that acquisition conditions remain unchanged.

• If you change the acquisition settings, history memory is cleared when you restart acquisition using the new settings.

• If CLEAR TRACE is pressed during waveform acquisition or after the waveform acquisition is stopped, data in the history memory are cleared when the data acquisition is restarted.

Precautions to be Taken when Recalling Data from the History Memory

• Acquisition will stop when the history memory menu is displayed. It is not possible to recall waveform data from the history memory while acquisition in progress.

• Acquisition can be restarted while the history memory menu is displayed. However, it is not possible to change history memory settings such as Selected Record No., while acquisition is in progress.

• Settings are restricted by the following formula. End Rec No. ≤ Selected Record No. ≤ Start Rec No.

• If you load a waveform record from floppy disk, or external storage device, the loaded waveform becomes Record 0. In the case of multiple records (sequential store), the records will be loaded sequentially, with the latest record as 0.

• Computation and automatic measurement of waveform parameters are always performed on the currently displayed waveform, i.e. the waveform identified by the record No. designated for Selected Record No. Analysis of old data is possible as long as the history memory content remains unchanged after acquisition is restarted. • In roll mode only the record most recently acquired when acquisition was stopped will

be loaded into record No. 0.

• Time at acquisition end is displayed under Show map.

• Turning OFF the power will delete the entire contents of the history memory.

Acquisition and Display

7

7.7

Searching the Historical Data Using Zone

(History Search Function)

<For a description of this function, see page 1-26>

Relevant Keys

ACTION DELAY

X - Y MENU MENU PHASE

SEARCH HORIZONTAL VERTICAL TRIGGER TRIG D HELP ESC SELECT RESET SIMPLE MODE POSITION MATH MISC FILE CLEAR TRACE HISTORY MEASURE SETUP PRESET DISPLAY CURSOR CH 1 CH 2 CH 3 CH 4 POWER

COPY IMAGE SAVE SHIFT

ZOOM GO/NO-GO ENHANCED ACQ START/STOP SNAP SHOT

V DIV TIME DIV

Operating Procedure

Selecting the Search Mode

1. Press HISTORY.

2. Pressing the Search Mode soft key displays the search mode selection menu.

3. Press the Zone soft key .

Selecting the Search Zone (Select Zone)

4. Pressing the Search Setup soft key displays the search condition setting menu.

5. Press the Select Zone soft key to display the search condition selection menu.

6. Press one of the soft keys corresponding to Zone1 to Zone4.

Setting the Search Conditions (Condition)

7. Press the Condition soft key several times to select OFF, IN, or OUT. Selecting IN or OUT displays a search window in the area displaying the Source channel.

Setting the Source Channel (Source)

8. Pressing the Source soft key displays the source channel selection menu. (CH3 and CH4 are not displayed on the DL1620.)

9. Press the soft key corresponding to the desired channel to select the source channel.

Setting the Search Window

10. Press the Upper Lower soft key.

11. Turn the jog shuttle to set the top of the search range. You can use the arrow keys to move between the digits. Pressing RESET resets the value to the default value. 12. Press the Upper Lower soft key.

13. Turn the jog shuttle to set the end of the search range. You can use the arrow keys to move between the digits. Pressing RESET resets the value to the default value.

14. By controlling both Upper and Lower using the jog shuttle, you can move the search window up and down without changing the vertical width.

15. In a similar fashion, set the horizontal range of the search window. 16. Repeat steps 6 to 15 to set Zone1 to Zone4.

Setting the Logic

17. Press the Logic soft key to select AND or OR.

Executing the Search

18. Press the Search Exec soft key to execute the search.