1.6 User Interface
1 – 13
such as “
3 )
”, to help guide the user to keypad entry values. Menus
with “Y
/
N” selections do not display the numeric labels; keypad “0”
corresponds to “No”, while “1” corresponds to “Yes”. Modified val-
ues will remail pending, with the indicator blinking above the [Enter]
button, until [Enter] is pressed or the pending value is cancelled.
1.6.3.4 Wheel entry
Any numeric value can also be edited by turning the wheel on the
front panel. Typically, this will begin incrementing (clockwise) or
6
decrementing (counterclockwise) the value being displayed, and
the pending lamp above the [Enter] button will begin flashing. In
this mode, the wheel behaves similarly to the numeric keypad,
and pending values await acceptance by [Enter], or cancellation by
[Clear
/
Cancel].
Several parameters also have a real-time entry feature. For these
parameters (see list, below), the wheel can be used to dynamically
modify the operating point of the instrument. To turn on this real-
time entry, press the [Live Entry] button adjacent to the wheel. If the
Live
indicator illuminates, then the wheel is now in real-time mode
and continuously modifying the parameter selected—in this mode,
there is no need to press the [Enter] button. Pressing [Live Entry] a
second time toggles the live mode o
ff
. Note that live mode is only
available when the TEC controller is on, or the laser diode driver is
on.
Parameters with live entry available:
•
Laser current setpoint (
SILD
, 4 – 20 )
•
Photodiode current setpoint (
SIPD
, 4 – 20 )
•
Photodiode power setpoint (
SWPD
, 4 – 21 )
•
Photodiode bias (
BIAS
, 4 – 26 )
•
Temperature setpoint (
TEMP
, 4 – 34 )
•
Resistance setpoint (
TRTH
, 4 – 34 )
•
TEC current setpoint (
TCUR
, 4 – 34 )
•
TEC
P
Gain (
TPGN
, 4 – 38 )
•
TEC
I
Gain (
TIGN
, 4 – 39
•
TEC
D
Gain (
TDGN
, 4 – 39 )
1.6.4
Local/Remote
When the LDC500 is commanded over the remote GPIB interface,
the
REM
indicator illuminates, showing that the instrument is in
“remote” mode. While
REM
is lit, the LDC500 will not respond
7
to front-panel key presses. To exit remote mode, press the [Util-
ity
/
Local] button.
LDC500 Series Laser Diode Controllers