Cropico DO6, Handbook

Page: 55 / 107

DO6 Handbook
Jan 2006 55 of 107 pages
7.3 General information
7.3.1 Interface watchdog timer
7.3.1.1 Timer A (response timer)
Timer A is used by the DO6 to protect itself from an invalid response or no response at all.
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Start: Timer A is started after data transfer has been terminated with
<ETX>. The instrument waits for an acknowledgement by the master.
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Stop: Timer A is stopped if a valid response <ACK> has been received.
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Timeout: If a timeout occurs the DO6 sends an <EOT> and returns to the initial
state (ready for a new command).
The timeout for Timer A is set to 5 seconds.
7.3.1.2 Timer B (receive timer)
Timer B is used by the DO6 to protect itself from the non recognition of the <ETX>
character.
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Start: Timer B is started after receiving the <STX> character.
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Restart: Timer B is restarted as long as data is being received in order to allow
variable datablock lengths to be received.
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Stop: Timer B is stopped if a valid response <ACK> has been received.
•
Timeout: If a timeout occurs, the received data (command) is discarded. The
DO6 returns to the initial state (ready for a new command).
The timeout for Timer B is set to 5 seconds.
8. SPCI commands
8.1 General information
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Command sections contained in [ ] are optional
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Commands have a long form and a short form; both forms are valid
o
The short form is written in upper case
o
The long form is written in lower case
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The individual command levels are separated by a colon
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There must be a space between the command and the first parameter
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The individual parameters are separated by a comma
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The individual responses are separated by a comma
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The query form of a command is terminated with a question mark
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The query form can also be sent at the same time as the parameters; in this case the
command is executed first and then the result (setting) returned.