Campbell CR3000 Micrologger, Руководство оператора

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Section 7. Installation
308
Term: RS-232C
Refers to the standard used to define the hardware signals and voltage levels.
The CR3000 supports several options of serial logic and voltage levels
including RS-232 logic at TTL levels and TTL logic at TTL levels.
Term: RX
Receive
Term: SP
Space
Term: start bit
Is the bit used to indicate the beginning of data.
Term: stop bit
Is the end of the data bits. The stop bit can be 1, 1.5 or 2.
Term: TX
Transmit
7.7.18.5 Serial I/O CRBasic Programming
To transmit or receive RS-232 or TTL signals, a serial port (see table CR3000
Serial Ports
(p. 305))
must be opened and configured through CRBasic with the
SerialOpen() instruction. The SerialClose() instruction can be used to close the
serial port. Below is practical advice regarding the use of SerialOpen() and
SerialClose(). Program CRBasic example Receiving an RS-232 String
(p. 315)
shows the use of SerialOpen(). Consult CRBasic Editor Help for more
information.
SerialOpen (COMPort,BaudRate,Format,TXDelay,BufferSize)
•
COMPort — Refer to CRBasic Editor Help for a complete list of COM
ports available for use by SerialOpen().
•
BaudRate — Baud rate mismatch is frequently a problem when
developing a new application. Check for matching baud rates. Some
developers prefer to use a fixed baud rate during initial development.
When set to -nnnn (where nnnn is the baud rate) or 0, auto baud-rate
detect is enabled. Autobaud is useful when using the CS I/O and RS-
232 ports since it allows ports to be simultaneously used for sensor and
PC comms.