Keithley 2657A, Reference Manual, Page: 184 / 805

Section 3: Functions and features Model 2657A High Power System SourceMeter® Instrument Reference Manual
3-70 2657A-901-01 Rev. B/December 2012
The display of the Model 2657A can be used to display user-defined messages. For example, while a
test is running, the following message can be displayed on the Model 2657A.
Test in Process
Do Not Disturb
The top line of the display can accommodate up to 20 characters (including spaces). The bottom line
can display up to 32 characters (including spaces) at a time.
The
display.clear()
,
display.setcursor()
, and
display.settext()
functions (which are
explained in the following paragraphs) are overlapped, nonblocking commands. The script will NOT
wait for one of these commands to complete.
These nonblocking functions do not immediately update the display. For performance considerations,
they write to a shadow and will update the display as soon as processing time becomes available.
Clearing the display
When sending a command to display a message, a previously defined user message is not cleared.
The new message starts at the end of the old message on that line. It is good practice to routinely
clear the display before defining a new message.
After displaying an input prompt, the message will remain displayed even after the operator performs
the prescribed action. The
clear()
function must be sent to clear the display. To clear both lines of
the display, but not affect any of the indicators, send the following function:
display.clear()
Cursor position
When displaying a message, the cursor position determines where the message will start. On power-
up, the cursor is positioned at row 1, column 1 (see the following figure). At this cursor position, a
user-defined message will be displayed on the top row (row 1).
Top line text will not wrap to the bottom line of the display automatically. Any text that does not fit on
the current line will be truncated. If the text is truncated, the cursor will be left at the end of the line.
Figure 64: Row/column format for display messaging
NOTE
XXXXXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
Row 1
Row 2
Columns (for Row 1) 1 20
Columns (for Row 2) 1 32
Display
X = display character