I am trying to connect my RS 232 port to the galil tools software to get a connection going . I tried connecting to various ports from the controller to the box with all my ports but my galil tools software keeps saying that the connection is offline and it doesn't connect. anybody have an idea on how to fix this ?
Warren on 06/10/2015 - 13:05
Between your computer and the DMC-4040, you will need to use a cable wired straight through (no null modem). The DMC-4040 in its default state also expects to use hardware handshaking so you'll need to make sure your cable has the RTS/CTS signals wired through if you don't alter the controller's configuration.
The RS-232 standard identifies expected connector configurations for Data Terminal Equipment (DTE) and Data Communications Equipment (DCE).
The DTE produces and uses the data and is found on each end of an RS-232 data link. In your case the DTE would be your computer and the DMC-4040.
The DCE provides the link between two pieces of DTE. A modem or a "null modem" is the classic example of DCE.
According to the standard, for a DB9 connector used on a piece of DTE, the connector should have pins and pin #2 should be the pin used by the DTE to receive data while pin #3 is used by the DTE to transmit data. You can do a Google search on "DTE DCE RS232 DB9 pinout" if you wish to see what other signals are on the other pins.
According to the standard, in the case of a DB9 connector used on a piece of DCE, the connector should always have socket contacts and contact #2 is expected to be the contact used by the DCE to transmit data while contact #3 is used by the DCE to receive data. This is exactly opposite to and complements the DTE pinout.
Every computer I've ever seen that uses a DB9 serial connector for RS232 uses a male connector configured as DTE, just like it should.
According to the DMC-4040 manual, it too uses a DB9M connector for its main serial port but it is configured as DCE in violation of the RS232 standard. IMHO the designers at Galil messed up on this.
MattK on 06/11/2015 - 09:48
Hello jcist001, When connecting to a Galil controller over serial, you will need to use a "straight thru" serial cable with hardware handshaking. This means that the RX, TX, RTS, CTS and GND lines must be connected. A quick google search will provide pinouts for these signals on the DB9 connector and the differences between a straight through and null modem serial cable. You can use a multimeter to ensure the proper connections are made between pins.
Once you have the proper cable, connecting to the controller involves selecting the proper COM port and baud rate in the GalilTools or GalilSuite connections window.
The decision to use a straight through serial cable was made on one of our first motion controllers, the DMC-100, in 1984. One of our top priorities has always been upward compatibility to make moving from generation to generation of controllers as simple as possible. In addition, despite the protocol standards, null modem cables are far more rare than straight through cables. For these reasons we've continued to include the straight through cable connection on all of our controllers.