MVME376工控备件模块
如果远程子网的大小超过“远程子网大小”组中定义的限制，则在连接时跳过该子网。该组包含：•最大值定义远程子网的最大大小。•如果绝对最大值小于最大值，则使用绝对最大值。OPC服务器DriveWindow 2 7-41搜索设备组该组定义是否使用广播方法在连接时搜索DDCS/UDP设备。通常情况下，您不会同时使用这两种方法。该组包含：•近表示使用本地以太网段UDP广播（IP=255.255.255.255，RFC 919）。•Intranet表示使用PC子网UDP广播（IP=IP或非子网掩码，RFC 922）。请注意，如果PC属于多个子网，则会广播所有子网。OPC服务器7-42 DriveWindow 2设备请求组该组定义用于查询DDCS/UDP设备存在的参数。如果您无法连接到DDCS/UDP设备，可以尝试增加Tries和/或Response Wait。缺点是连接和可能断开连接的时间将增加。该组包含：•Tries定义如果使用广播方法并且查询IP地址的最大尝试次数，则发送广播消息的次数。•响应等待是对查询的响应等待的时间（广播方法）或最长时间（IP地址）。•Parallel Requests是在开始等待响应之前发送的查询消息数。•在广播查询中使用静音时间，以防止已找到的DDCS/UDP设备在继续进行广播查询时引起不必要的响应。OPC服务器DriveWindow 2 7-43 DDCS读取超时组该组定义各种DDCS读取消息的超时。如果在找到DDCS/UDP设备（DDCS/UDP配置对话框中的测试按钮）时，在DDCS网络中找到连接到DDCS/UDP的驱动器时遇到困难，可以尝试增加标识超时。缺点是连接时间会增加。通过限定DDCS节点组中的节点数量，可以补偿增加的数量。请注意，状态和数据超时可以显著延长，而不会降低通信速度，因为它们实际上在UDP消息丢失时生效。如果系统软件备份/恢复有问题，可以尝试增加数据读取超时。该组包含：•状态定义DDCS/UDP设备DDCS寄存器读取的超时。•日期定义从DDCS网络中的驱动器获取响应的超时。•Identify告诉在查询DDCS网络中的驱动器是否存在时等待驱动器响应的最长时间。请注意，文件DWC_def.ini的[DWC_DDCS]部分中的recshorttimeout_ms可以延长所有设备的超时时间。OPC服务器7-44 DriveWindow 2 DDCS节点组该组定义驱动器的节点号以及DDCS/UDP设备的DDCS网络中是否存在分支单元。这些设置用于缩短启动时间，以防您对DDCS网络有详细了解。通常，查询DDCS网络中所有节点号（1…254）的存在，并默认假设存在分支单元。该组包含：•节点列表是一个以逗号分隔的节点列表或驱动器节点编号的节点范围，可查询是否存在。范围-n表示1-n，n-表示n-254。•分支单元可用于指定DDCS/UDP设备的DDCS网络中没有分支单元。设备地址组该组定义IP地址（固定IP）或IP地址和子网掩码（远程子网）。
A Remote Subnet is skipped at connection time if its size exceeds the limits defined in the Remote Subnet Size group. The group contains: • Maximum defines the maximum size of a remote subnet. • Absolute maximum is used instead in case it is less than Maximum. OPC Server DriveWindow 2 7-41 Search Devices group The group defines, whether the broadcast methods are used to search DDCS/UDP devices at connection time or not. Typically you never use both of them. The group contains: • Near means that local Ethernet segment UDP broadcast (IP=255.255.255.255, RFC 919) is used. • Intranet means that the PC subnet UDP broadcast (IP=IP or not subnet mask, RFC 922) is used. Note that if the PC belongs to several subnets, all of them are broadcasted. OPC Server 7-42 DriveWindow 2 Device Request group The group defines parameters for querying presence of DDCS/UDP devices. If you have trouble to connect to DDCS/UDP devices, you can try to increase Tries and/or Response Wait. The drawback is that connect and possibly disconnect times will increase. The group contains: • Tries defines how many times a broadcast message is sent if a broadcast method is used and maximum number of tries an IP address is queried. • Response Wait is the time (broadcast methods) or maximum time (IP address) a response to a query is waited for. • Parallel Requests is the number of query messages sent before starting to wait responses. • Mute Time is used in broadcast queries to prevent already found DDCS/UDP devices causing unnecessary responses while further broadcast queries are still made. OPC Server DriveWindow 2 7-43 DDCS Read Timeout group The group defines timeouts for various DDCS read messages. If you have trouble to find the drives in the DDCS network connected to the DDCS/UDP device when the DDCS/UDP device is found (Test button in DDCS/UDP Configuration dialog box), you can try to increase Identify timeout. The drawback is that connect time will increase. By delimiting number of nodes in the DDCS Nodes group you can compensate the increase. Note that Status and Data timeouts can be prolonged considerably without slowing down the communication speed because they actually take effect just when an UDP message is lost. If you have problems with system software backup/restore you can try to increase the Data read timeout. The group contains: • Status defines the timeout for DDCS/UDP device DDCS register read. • Date defines the timeout for getting response from a drive in the DDCS network. • Identify tells the maximum time to wait a response from a drive in the DDCS network when querying its presence.Note that the timeout for all devices can be prolonged by recshorttimeout_ms in the [DWC_DDCS] section of the file dwc_def.ini. OPC Server 7-44 DriveWindow 2 DDCS Nodes group The group defines the node numbers of drives and whether there is a branching unit in the DDCS network of the DDCS/UDP device. These settings are used for shortening the start-up time in case you have detailed knowledge about the DDCS networks. Typically presence of all node numbers (1...254) in a DDCS network is queried and the presence of branching units is assumed by default. The group contains: • Node List is a comma separated list of nodes or node ranges of drive node numbers, presence of which are queried. A range -n means 1-n and n- means n-254. • Branching Unit can be used to specify that there are no branching units in the DDCS network of the DDCS/UDP device. Device Addresses group The group defines the IP address (Fixed IP) or an IP address and subnet mask (Remote Subnet).
