CTI 2572-A, Installation And Operation Manual

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CTI 2572-A Installation and Operation Guide V1.3 33
Offset 3 Protocol Manager Number - Protocol Managers control the operation of the serial and
network ports. The Protocol Manager Number for the CAMP Client protocol
manager is decimal 36 (hex 24).
Offset 4 Startup Option Bits -
Bits 1 - 14 Bit 15 - IP Address Location Bit 16
Reserved 0 = Use IP Address in C
REATE
S
OCKET
Command Block.
1 = Use IP Address in M
EMORY
T
RANSFER
Command
Block (UDP Only)
Not Used
in 2572-A
When bit 15 is set to 1 (Offset 4 = 0x0002) and the UDP protocol is selected (in
Offset 5), the Command Blocks used for Memory Transfer (R
EAD
R
EMOTE
, W
RITE
R
EMOTE
, and M
EMORY
E
XCHANGE
) will specify the IP Address and Port Number for
the remote device.
This feature allows you to use a single socket to communicate with different remote
devices. When bit 15 is set to 0, the IP address and port number entered in this
C
REATE
S
OCKET
command block will be used. The TCP protocol, since it is
connection-oriented, will always use the IP address and port number in this C
REATE
S
OCKET
command block. If you select TCP and set bit 15 to 1, the 2572-A will
return an error.
NOTE:
Even if you set bit 15 to 1, you still must provide a valid IP address and Port number in the Command
Block of the C
REATE
S
OCKET
command. If you don’t do this, a Command Error will be generated
when you execute the C
REATE
S
OCKET
command.
Offset 5 Type of Service - Selects TCP or UDP/Multicast service. Using TCP, a connection is
established with the other node. If the TCP connection cannot be established, the
2572-A will indicate an error. Using UDP/Multicast, the local socket is created but
no connection is established with the target node.
NOTE:
If TCP is selected and the connection with the target node (remote host) is lost, the 2572-A will report
a socket connection error code (such as 240A - Socket not Connected) the next time you attempt to
read/write data. After the error is acknowledged, the 2572-A will complete error recovery by
automatically closing the socket. A subsequent attempt to read/write data will result in a 00A6
(connection not active) error. See Appendix B for error code listings. Your logic should re-execute
the Create Socket command if the connection is not active.
Offset 6-7 IP Address - If the IP A
DDRESS
S
ELECTION
option bit in Offset 4 is set to 0, these
words specify the IP address of the destination node. Since the IP address consists of
32 bits, the address is contained in two 16 bit words. An IP address of 0.0.0.0 will
return an error. If you are using TCP, the largest valid IP address is 223.255.255.255.
If you are using UDP/Multicast, you can also enter multicast addresses ranging from
224.0.0.2 through 239.255.255.255.
Offset 8 Unused - This word is not used when creating a TCP/IP socket. It should be set to 0.