Red Lion GEMINI 52 - Manual (Page 27)

SENDING COMMANDS & DATA TO THE GEM52 [Cont’d]
As shown, all commands must be terminated with a “Command Terminator”
(* or 2AH). The Gemini 5200 will not process the command until the terminator
is sent. If illegal commands or characters are sent to the Gemini 5200, they still
would need to be terminated by an (*). If they are not terminated, the next
command will not be accepted.
When writing application programs in Basic, the transmission of spaces or
carriage return and line feed should be inhibited by using the semicolon delimiter
with the Print statement. The Gemini 5200 will not accept a carriage return or line
feed as valid characters. See “Terminal Emulation Program” section for a listing
of a terminal emulation program written in Basic.
When a “Change Value” command is sent to the Gemini 5200, a short amount
of time is required for the unit to process the data. This time increases with the
count rate. During this time, only one additional command may be sent to the
Gemini 5200. This may be done 80 msec after the transmission of the “Change
Value” command. After the second command has been transmitted, the unit will
ignore any further commands until 10 msec after both the “Change Value” and
second command have been processed. It is recommended that a “Transmit
Value” command follow a “Change Value” Command. If this is done, the
reception of the data can provide a timing reference for sending another
command and will insure that the change has occurred.
Note: When Preset tracking is enabled, before changing Preset 2 via serial
communications, the Preset 2 value must be interrogated in order to establish
the Preset 1 value.
The timing diagrams show the timing considerations that need to be made.
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FIG. 2: TIMING FOR SENDING COMMANDS
FIG. 3: RESET COMMAND TIMING
(**) This is the time that it takes the Gemini 5200 to process the preset. It
varies with the Count Rate and Scale Factor Value.