Galil Motion Control RIO-47120, Руководство пользователя

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TCP/IP is a "connection" protocol. The master must be connected to the slave in order to begin
communicating. Each packet sent is acknowledged when received. If no acknowledgement is received, the
information is assumed lost and is resent.
Unlike TCP/IP, UDP/IP does not require a "connection". This protocol is similar to communicating via
RS232. If a cable is unplugged, the device sending the packet does not know that the information was not
received on the other side. Because the protocol does not provide for lost information, the sender must re-
send the packet.
Galil recommends using TCP/IP for standard communication to insure that if a packet is lost or destroyed
while in transit, it will be resent. However UDP is recommended in certain situations such as launching Data
Record information to a host for graphing or data collection.
Each packet must be limited to 470 data bytes or less. This is not an issue when using Galil software as the
Galil Ethernet driver will take care of the low level communication requirements.
The IK command blocks the controller from receiving packets on Ethernet ports lower than 1000 except for
ports 0, 23, 25, 68, 80 and 502. To receive packets on all ports, set IK to 0.
NOTE:
In order not to lose information in transit, Galil recommends that the user wait for an
acknowledgement of receipt of a packet before sending the next packet.
Jumper Configuration for 10BaseT
If 10BaseT communication is required, a jumper must be placed on the pins labeled OPT. The default is no
jumper which is 100BaseT Ethernet communication.
Addressing
There are three levels of addresses that define Ethernet devices. The first is the MAC or hardware address.
This is a unique and permanent 6 byte number. No other device will have the same MAC address. The RIO
MAC address is set by the factory and the last two bytes of the address are the serial number of the board.
To find the Ethernet MAC address for a RIO unit, use the TH command. A sample is shown here with a unit
that has a serial number of 3:
Sample MAC Ethernet Address: 00-50-4C-28-00-03
The second level of addressing is the IP address. This is a 32-bit (or 4 byte) number that usually looks like
this: 192.168.15.1. The IP address is constrained by each local network and must be assigned locally.
Assigning an IP address to the RIO board can be done in a number of ways.
The first method for setting the IP address is using a DHCP server. The DH command controls whether the
RIO board will get an IP address from the DHCP server. If the unit is set to DH1 (default) and there is a
DHCP server on the network, the controller will be dynamically assigned an IP address from the server.
Setting the board to DH0 will prevent the controller from being assigned an IP address from the server.
The second method to assign an IP address is to use the BOOT-P utility via the Ethernet connection. The
BOOT-P functionality is only enabled when DH is set to 0. Either a BOOT-P server on the internal network
or the Galil software may be used. When opening the Galil Software, it will respond with a list of all RIO
boards and controllers on the network that do not currently have IP addresses. The user must select the board
and the software will assign the specified IP address to it. This address will be burned into the controller
(BN) internally to save the IP address to the non-volatile memory. Note: if multiple boards are on the
network – use the serial numbers to differentiate them.
CAUTION: Be sure that there is only one BOOT-P or DHCP server running. If your network has
DHCP or BOOT-P running, it may automatically assign an IP address to the RIO board upon linking
it to the network. In order to ensure that the IP address is correct, please contact your system
administrator before connecting the I/O board to the Ethernet network.
RIO-47xxx Chapter 3 Communication ● 11