Campbell Scientific CR3000 CR3000 Micrologger - Page 210

Section 7. Installation • BaudRrate - 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 telecommunications. • Format - Determines data type and if PakBus® communications can occur on the COM port. If the port is expected to read sensor data and support normal PakBus® telemetry operations, use an auto-baud rate argument (0 or nnnn) and ensure this option supports PakBus® in the specific application. • BufferSize - The buffer holds received data until it is removed. SerialIn(), SerialInRecord(), and SerialInBlock() instructions are used to read data from the buffer to variables. Once data are in variables, string manipulation instructions are used to format and parse the data. SerialClose() must be used before SerialOpen() can be used again to reconfigure the same serial port, or before the port can be used to communicate with a PC. 7.8.8.5.1 Input Instruction Set Basics SerialOpen()1 • Be aware of buffer size (ring memory) • Closes PPP (if active) • Returns TRUE or FALSE when set equal to a Boolean variable SerialClose() • Examples of when to close o Reopen PPP o Finished setting new settings in a Hayes modem o Finished dialing a modem • Returns TRUE or FALSE when set equal to a Boolean variable SerialFlush() • Puts the read and write pointers back to the beginning • Returns TRUE or FALSE when set equal to a Boolean variable SerialIn()1 • Can wait on the string until it comes in • Timeout is renewed after each character is received • SerialInRecord() tends to obsolete SerialIn(). • Buffer-size margin (one extra record + one byte) SerialInBlock()1 • For binary data (perhaps integers, floats, data with NULL characters). • Destination can be of any type. 210