PDL Async protocol

PDL Async is a PDL-based driver for asynchronous serial interfaces. Communications through RS-232 connections are asynchronous in nature. For asynchronous communications, specify the port number and the behavior characteristics such as baud rate, number of data bits, parity, and other characteristics.

PDL Options pane

This table shows the parameters in the PDL Options and PDL Async panes:

Parameter Description
PDL Click List to view a predefined list of PDL script names.
Line The first device name. For example, tty0.
Modem Specify the modem initialization string to be used when the driver starts. A typical string is ATZ, which clears the modem registers for most modems.
Error Log Specify the error file name. This is optional.
Baud Click to open a menu of bandwidth rate options.
Bits After the start bit has been sent, the transmitter sends the actual data bits. Menu choices are 5, 6, 7, or 8 data bits. Both the receiver and transmitter must agree on the number of data bits, and the baud rate. Most devices transmit data using 7 or 8 data bits.
Parity A method of detecting errors in transmission. Click to open a menu of parity bit choices: None, Odd, or Even.
Require carrier Select this to require the carrier signal online before connecting.
Use RTS/CTS Select this to use hardware flow control.
Use XON/XOFF Select this to use software flow control.
Use 8 Bit Select this to enable ISTRIP.

Auto-Reconnect Options pane

This table shows the parameters in the Auto-Reconnect Options pane:

Parameter Description
Auto-reconnect Select this to automatically reestablish a broken connection.
Reopen Time Specify the minimum number of seconds to wait after connection failure before reconnection. The default is 5. This option is available only when Auto-reconnect is selected.

Start-up Procedures pane

Click Edit to open the TPS Editor. Use this to select the procedures to run when the thread starts. This is a TPS (Tcl Procedure Stream). Use it to trade messages with the remote end.

Configuration keys

The engine constructs use these keys to configure PDL Async with configuration lists:

  • TYPE: async
  • NAME: PDL name
  • BAUD : baud rate
  • PARITY: parity
  • DATA-BITS: word size
  • PATH: /dev/ttyname
  • REQUIRE-CD: Require Carrier Detect (boolean)
  • HW-FLOW-CONTROL: Use RTS/CTS flow control (boolean)
  • XON-XOFF: Use software flow control (boolean)