csmstr - Omega Engineering

USING RAW PORTS
SENDING DATA
The example above listens on a TCP/IP socket for a frame that starts with an asterisk and
ends with a carriage return. It then converts the frame to a decimal value, stores this in an
integer tag, and echoes the value back to the client.
SENDING DATA
To send data on a raw port, use the PortWrite or PortPrint functions, as documented in
the Function Reference section of this manual. The first function sends a single byte, while
the second function sends an entire string. To send numeric values, use the IntToText
function to convert them into strings.
NOTES FOR EDICT USERS
Users of Red Lion’s Edict-97 software should note…
• The raw serial port device driver controls the port’s handshaking lines, so there
is no need to call SetRTS, HoldTx or any of the various other port management
functions. These functions are thus not provided by Crimson.
• When sending data, Crimson automatically handles buffer overflow events, and
ensures that no data is lost. The PortWrite and PortPrint thus neither provide
a return value, nor is such a value required.
• To directly emulate GAF, use a program similar to the example shown above,
but store the received string in a string tag, and increment an integer tag. Such
direct emulation is not recommended, as you will nearly always then have a
trigger to respond to the change in the sequence number, in which case you
might as well handle this logic within the communications program.
• Crimson’s enhanced programming support allows much higher performance
levels when using raw port drivers. Performance typically exceeds that of the
equivalent Edict configuration by an order of magnitude or more.
REVISION 6 PAGE 273