Sutter Instrument Lambda 10-3, Руководство по эксплуатации

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LAMBDA 10-3 OPERATION MANUAL – REV. 3.03 (20110829)
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8.4.3
8.4.3 8.4.3
8.4.3 Using the BUSY Line
Using the BUSY Line Using the BUSY Line
Using the BUSY Line
Reading the status of the BUSY BUSY BUSY BUSY line would allow the host computer to determine if the unit
is ready to receive a command, if a command has been received, and when the new filter has
been placed in position. Obviously, it is also possible for the host computer to control the
timing of events based on the expected behavior of the LAMBDA 10
LAMBDA 10 LAMBDA 10
LAMBDA 10----3
3 3
3 (as described above)
using the BUSY
BUSY BUSY
BUSY line only to verify that the controller is in the expected state.
The status of the BUSY BUSY BUSY BUSY line could also be used as a condition for timing other events. For
instance, the dropping of the BUSY BUSY BUSY BUSY line could be used as the trigger for opening a shutter or
beginning data collection. Using the BUSY BUSY BUSY BUSY line to trigger other events automatically allows
for time required to recover time from errors. The BUSY BUSY BUSY BUSY line can even be used as an
indication that an error has occurred. If the BUSY BUSY BUSY BUSY line fails to go low at the expected time
after a new command was issued, it may be assumed that the controller has detected an error
and the filter wheel is in the process of recovering.
8.4.4
8.4.4 8.4.4
8.4.4 Using the ERROR Line
Using the ERROR Line Using the ERROR Line
Using the ERROR Line
The ERROR ERROR ERROR ERROR line signals when an ERROR ERROR ERROR ERROR in Filter Wheel movement has been detected. The
ERROR ERROR ERROR ERROR line normally would not be used to determine timing of program execution in the
host computer, since it is active only after an error and, even then, it is not held high during
the entire ERROR recovery process. The use of the ERROR
ERROR ERROR
ERROR line will depend on two factors
What are the consequences of an error? What are the consequences of an error? What are the consequences of an error? What are the consequences of an error? Continuing normal program execution in the
host computer during recovery from an error might cause problems such as wasted data
storage, exposure of sensitive photo detectors, experimental preparation to strong light;
or the recording of faulty data.
What is the burden placed on the hos What is the burden placed on the hos What is the burden placed on the hos What is the burden placed on the host computer in checking the ERROR line. t computer in checking the ERROR line. t computer in checking the ERROR line. t computer in checking the ERROR line. The
ERROR
ERROR ERROR
ERROR line will go high only after a move that has been completed incorrectly, and will
remain high only during part of the recovery from that error. Thus, the host computer
would have to read the status of the ER
ER ER
ERROR
ROR ROR
ROR line just at the point in time at which data
collection should begin.
8.5 8.5 8.5 8.5 Using a Computer’s Parallel (Printer) Port Using a Computer’s Parallel (Printer) Port Using a Computer’s Parallel (Printer) Port Using a Computer’s Parallel (Printer) Port
The standard PC parallel port provided for printer control may be used to control the
LAMBDA 1
LAMBDA 1 LAMBDA 1 LAMBDA 10 0 0 0----3 3 3 3. This, however, does not mean that instructions can be sent to the LAMBDA LAMBDA LAMBDA LAMBDA
10 10 10 10----3 3 3 3 in the same manner that they are sent to a printer. A printer is designed to print at its
maximum rate and, if the computer generates output at a higher rate, the printer will store
the output in a buffer until the mechanism is ready. If the buffer becomes full, the printer
will indicate to the computer that it is not ready to accept more data. It follows that there is
not a tight time relationship between the output of a command from the computer and the
execution of that command by the printer.
The time relationship between output of data from the computer and response by the
LAMBDA 10
LAMBDA 10 LAMBDA 10 LAMBDA 10----3 3 3 3, in contrast, must be very tight. Thus, it is understandable that the mode
with which the parallel port is used will differ somewhat for the LAMBDA 10 LAMBDA 10 LAMBDA 10 LAMBDA 10----3 3 3 3 from that of a
printer.
The details of the input and output signals were described in previous sections. Now we will
discuss the way in which these signals may be used to control the LAMBDA
LAMBDA LAMBDA LAMBDA 10 10 10 10----3 3 3 3 from a PC
computer's parallel printer port. This information is provided as a limited example and is