It is good practice to check for : after each command is sent to prevent errors. An echo function is provided to
enable associating the DMC-41x3 response with the data sent. The echo is enabled by sending the command EO 1
to the controller.
Unsolicited Messages Generated by Controller
When the controller is executing a program, it may generate responses which will be sent via the USB port or
Ethernet handles. This response could be generated as a result of messages using the MG command OR as a result
of a command error. These responses are known as unsolicited messages since they are not generated as the
direct response to a command.
Messages can be directed to a specific port using the specific Port arguments – see the MG and CF commands in
the Command Reference. If the port is not explicitly given or the default is not changed with the CF command,
unsolicited messages will be sent to the default port. The default port is the main serial port. When
communicating via an Ethernet connection, the unsolicited messages must be sent through a handle that is not the
main communication handle from the host. The GDK software automatically establishes this second
communication handle.
The controller has a special command, CW, which can affect the format of unsolicited messages. This command is
used by Galil Software to differentiate response from the command line and unsolicited messages. The command,
CW1 causes the controller to set the high bit of ASCII characters to 1 of all unsolicited characters. This may cause
characters to appear garbled to some terminals. This function can be disabled by issuing the command, CW2. For
more information, see the CW command in the Command Reference.
USB and RS-232 Ports
The USB port by default is an interpreted serial communication port for the DMC-41x3 and will receive and
respond to DMC commands. The RS232 (DB9) port is the auxiliary port by default, and is used to connect to
external devices that do not use DMC code, such as bar code readers or other RS232 sensors and displays. The
controller can read and write generic data but the user must write their own communication routines. A full
description of the USB and RS232 default configuration settings can be found in the following sections.
The US command (Rev D firmware or greater) can reverse the main and auxiliary port such that the RS232 port
would interpret DMC commands and the USB port would be available for generic data. The following are several
points to consider when switching the USB and RS232 ports with US.
• A null modem cable is required for interfacing to the RS232 port. Baud rates are set via the controller's
jumpers.
• Firmware cannot be loaded from the RS232 port. The user must switch back to USB mode to load
firmware via serial. Ethernet firmware updates are supported in both modes.
• When using the USB port in swapped mode, the remote device must interface to the USB to serial
converter on the controller. On a PC this is done with a device driver. The USB to serial UART is an FT232
from FTDI.
See the US command in the command reference for further detail. Contact Galil if a permanent swap is required.
Several options are available.
USB Port
The USB port on the DMC-41x3 is a USB to serial converter. It should be setup for 115.2kB, 8 Data bits, No Parity, 1
Stop Bit and Flow Control set for Hardware. The baud rate can be changed to 19200 baud by installing the 19.2
jumper on JP1, but this configuration is only recommended if a slower baud rate is required from the host
Chapter 4 Software Tools and Communication ▫ 39 DMC-41x3 User Manual
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