Sutter Instrument Lambda 10-3, Operation Manual

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LAMBDA 10-3 OPERATION MANUAL – REV. 3.03 (20110829)
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communication that you use. In Microsoft QuickBasic the communication channel may be
opened with a statement such as:
OPEN "COM1:9600,N,8,1, CD0,CS0,DS0 " FOR RANDOM AS #1 LEN = 256
This sets COM1 to the correct mode for bi-directional communication through channel #1.
The option list “CD0,CS0,DS0” causes QuickBasic to ignore the DCD, CTS and DSR control
lines. Other variants of the BASIC programming language (implemented for the PC) will
have a similar syntax for the above statement.
6.2
6.2 6.2
6.2 Input Command Set and Protocol
Input Command Set and Protocol Input Command Set and Protocol
Input Command Set and Protocol
Input Commands to the controller via the serial port are structured and adhere to the same
protocol as described in the REMOTE CONTROL chapter. The Filter, Shutter, and Special
commands, as described in the REMOTE CONTROL chapter, all apply to the serial port
interface. Each command consists of one byte (8-bits), and some commands are followed by
one or more bytes as parameters. The command protocol is the same as described in Chapter
5 (EXTERNAL COMMAND CONTROL): As a command is sent to the controller, it is
immediately echoed back to the computer, and when the controller has completed the task
associated with the command it has just received, it sends an ASCII CR (carriage return)
byte (13 decimal, 0D hexadecimal) to the computer.
Since the serial data stream format is a single byte, each command can be sent as an ASCII
character. If you have used a
BASIC language open statement to establish serial
communications the subsequent 8 bit command values may be sent using a BASIC PRINT #
command such as:
PRINT #1, CHR$(DATANUM);
…where #1 is the file number used in the open statement, and DATANUM is the value of
the command to be sent. Note that the CHR$ function allows the actual number to be sent
rather than the ASCII numbers of the characters that represent the number. Sending “;”
disables the automatic addition of characters such as a linefeed or a space.