User`s guide

Serial Line I/O
The V+ controller has several serial lines that are available for general use. This section
describes how these lines are used for simple serial communications. To use a serial line for a
special protocol such as DDCMP and Kermit (described later in this chapter), the line must be
configured using the Adept controller configuration utility program.
1
I/O Configuration
In addition to selecting the protocol to be used, the Adept controller configuration program
allows the baud rate and byte format for each serial line to be defined. Once the serial line
configuration is defined on the V+ system boot disk, the serial lines are set up automatically
when the V+ system is loaded and initialized. After the system is running, the FSET program
instruction can be used to reconfigure the serial lines. The following byte formats are
available:
l Byte data length of 7 or 8 bits, not including parity
l One or two stop bits
l Parity disabled or enabled
l Odd or even parity (adds 1 bit to byte length)
The following baud rates are available:
110, 300, 600, 1200, 2400, 4800, 7200, 9600, 19200, 38400
In addition, V+ provides automatic buffering with optional flow control for each serial line.
The I/O configuration program can be used to enable output flow control with which V+
recognizes Ctrl+S (19 decimal) and Ctrl+Q (17 decimal) and uses them to suspend and
resume, respectively, serial line output. The configuration program can also enable input
flow control, with which V+ generates Ctrl+S and Ctrl+Q to suspend and resume,
respectively, input from an external source. With Ctrl+S and Ctrl+Q flow control disabled, all
input and output is totally transparent, and all 8-bit data bytes can be sent and received.
Serial lines may also be configured to use hardware modem control lines for flow control.
(The RTS/CTS lines must be installed in the modem cable-standard modem cables often
leave these lines out.) For pin assignments, see the documentation on serial I/O connectors
in the Adept SmartController User's Guide or Adept MV Controller User's Guide.
Attaching/Detaching Serial I/O Lines
Serial lines must be attached before any I/O operations can take place. Note that only one
control program task can be attached to a single serial line at any one time. All other
attachment requests will queue or fail, depending on the setting of the mode parameter in
the ATTACH program instructions.
Attaching or detaching a serial line automatically stops any output in progress and clears all
input buffers. Serial lines are not automatically detached from a program unless it completes
Serial Line I/O
(Undefined variable: Primary.Product_Name_V)Language User's Guide, version
17.x
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