4 – 60
Remote Operation
4.6.3.1 Standard event status enable (ESE)
The ESE acts as a bitwise AND with the ESR register to produce the
single-bit ESB message in the Status Byte Register (SB). The register
can be set and queried with the
*ESE(?)
command.
At power-on, this register is cleared.
4.6.4
Laser diode condition (LDCR)
The Laser Diode Condition Register consists of 10 condition flags
that reflect the real-time condition of the LD portion of the LDC500.
Reading the
LDCR
has no e
ff
ect on any values.
Weight
Bit
Flag
1
0
LD ON
2
1
CC
/
CP
4
2
BW
8
3
SCANNING
16
4
LD STABLE
32
5
ILIM
64
6
PLIM
128
7
VLIM
256
8
INTERLOCK
512
9
RANGE
LD ON : Set when the LD current source is on.
CC
/
CP : Set when the LD current source is in CP mode.
BW : Set when the LD current source is in high bandwidth mode.
SCANNING : Set when a multi-point scan is in progress (see
SCAN
).
LD STABLE : Set when laser current is stable.
ILIM : Set when the LD current source is at the current limit (
SILM
).
PLIM : Set when the photodiode reading is above the limit value (either
PILM
or
PWLM
).
VLIM : Set when the LD forward voltage is within 250 mV of the volt-
age limit (
SVLM
).
INTERLOCK : Set when the external interlock is open.
RANGE : Set when LD range is high (500 mA).
4.6.4.1 Laser diode positive/negative transition (LDPT/LDNT)
These two 16-bit wide registers control the mapping of transitions in
the LDCR to setting flags in the LDEV register. For any particular
event, if the corresponding bit is set in LDPT, then a 0
→
1 transition
LDC500 Series Laser Diode Controllers
