[2G] Serial over IP

• Overview
• Type 1 (Dumb Redirection)
• Type 2 (Guest Mode)
• Type 3 (CLI Access)

Overview

Just Add Power supports 3 Types of serial management of endpoint devices:

• Type 1: Commands enter the system via the RS232 port on a Transmitter. Commands are passed to all Receivers watching that Transmitter. The Receivers pass the command through the RS232 port. 2-directional, can pass from Receiver to Transmitter in the same way.
• Type 2: Commands enter the system via an IP telnet connection to port 6752 of a Transmitter or Receiver. The command passes out of the RS232 port. 2-directional, can receive commands from the endpoint device to the telnet session.
• Type 3: Commands enter the system via an IP telnet connection to port 23 of a Transmitter or Receiver. The Linux shell redirects the commands to the RS232 port. 1-directional; can only send commands.

Type 1 (Dumb Redirection)

Description

Any serial commands sent into a Transmitter are sent out the RS232 port of all connected Receivers. Any serial commands sent into a Receiver are sent to the RS232 port of the Transmitter it is watching.

* Baud-rate settings and pin-outs on Transmitter and Receiver must match. Straight-through RS232 extension over IP.

Usage

Serial strings input to the RS232 port of a Transmitter are output from the RS232 port of all Receivers actively watching that Transmitter. Serial strings input to the RS232 port of a Receiver are output from the RS232 port of the Transmitter that the Receiver is watching.

Baud rate of the control system, the Receiver, and the Transmitter must match the baud rate of the serial-controlled device.

Type 2 (Guest Mode)

Description

A TCP connection is made from the control system to the IP address of a Transmitter or Receiver at  TCP port 6752. Type 2 offers 2-directional serial communication: the control system sends commands to the endpoint serial device, and the endpoint serial device can respond to the control system. Serial commands sent via Type 2 are sent via the IP connection of the control system not a serial port.

* Transmitter and Receiver must be linked together in order to access serial port.

Usage

The serial port of the device is written by opening a telnet socket to port 6752 of the device. The open socket provides direct 2-way access to the serial port of the Just Add Power device. Commands are passed through as entered.

Baud rate of the Just Add Power device must match the baud rate of the serial-controlled device.

Type 3 (CLI Access)

Description

A TCP connection is made from the control system to the IP address of a Transmitter or Receiver at TCP port 23 (standard telnet). Type 3 offers 1-directional serial communication: the control system sends commands to the endpoint serial device; no feedback is registered. Serial commands sent via Type 3 are sent via the IP connection of the control system not a serial port.

Usage

The serial port of the device is written using the 'printf' function through the standard command line interface.

Command format:

stty 9600 -F /dev/ttyS0;printf "SERIAL_CODE_HERE" > /dev/ttyS0

Hex formatted characters in the serial code must be specially formatted by preceding each Hex pair with \x

Example: Samsung displays use Hex characters for serial control. The command for power on is 08 22 00 00 00 02 D4. To send that through Type 3, send:

stty 9600 -F /dev/ttyS0;printf "\x08\x22\x00\x00\x00\x02\xD4" > /dev/ttyS0