dtmf relay

PLC uses a ladder chart language that is extremely similar to the circuit diagram of the relay. If PLC is used to transform the relay control system, it is a shortcut to design a ladder chart based on the relay circuit diagram. This is because the original relay control system has been used and tested for a long time a

Profile This article describes how to configure a remote domain for the Internet Information Services (IIS) Simple Mail Transfer Protocol (SMTP) mail relay server. IIS in Windows Server 2003 includes a full-featured SMTP virtual server that you can use to deliver messages on your internal network. The SMTP virtual server can also be used to accept messages from the Internet. Although the SMTP service does not provide an easily accessible message retri

In the networking settings of the DHCP server, we sometimes involve DHCP Relay content. Next, we will explain how to use DHCP Relay to bind IP addresses and MAC addresses. I hope it will be helpful to you. Functional requirements and networking description Use DHCP Relay to bind IP addresses and MAC addresses "Configure Environment Parameters 』 1. the IP address

The relay drive current generally needs to be 20-40ma or larger, the coil resistance is 100-200 ohm, so the drive circuit should be added1. The transistor is used to drive the relay and the transistor's emitter must be grounded. Detailed circuits such as the following:NPN transistor PNP transistor NPN Transistor driver: When the transistor T1 base is input high, the transistor saturation conduction, the co

Article Title: Application of mail relay on a Linux server. Linux is a technology channel of the IT lab in China. Includes basic categories such as desktop applications, Linux system management, kernel research, embedded systems, and open source. Yesterday I received a help call from the apprentice. He said that he deployed the Sendmail mailbox server on the Linux server. However, we encountered a strange problem. You cannot use the client software to

R1: VLAN 2 Interface fastethernet1/0 Switchport Access VLAN 100 ! Interface FASTETHERNET1/1 Switchport Access VLAN 100 ! Interface FASTETHERNET1/2 Switchport Access VLAN 100 R2: Interface Tunnel23 No IP address No IP route-cache Tunnel Source fastethernet0/0 Tunnel Destination 192.168.234.3 ! Interface Tunnel24 No IP address No IP route-cache Tunnel Source fastethernet0/0 Tunnel Destination 192.168.234.4 ! Interface fastethernet0/0 IP address 192.168.234.2 255.255.255.0

Tags: mysql relay_log failure master-slave copyFirst, the problem descriptionIn MySQL master-slave replication mode, slave reported the wrong "relay log read failure", causing the master-slave synchronization to stop.Mysql> Show Slave Status\g1. Row ***************************Slave_io_state:master_host:10.0.0.93Master_user:slaveusermaster_port:3306Connect_retry:60 master_log_file:dd-bin.002542read_master_log_pos:752973519relay_log_file:dd-

LINUX 6 builds an experiment as a DHCP server--and uses a DHCP relay link------------------------------------DHCP-------------------------------------------DHCP Relay Agent--to help the DHCP service broadcast across VLANs- How DHCP is assigned:1. Automatic assignment: Permanent use after assigning to an IP address2. Manual assignment: The IP address is specifically specified by the DHCP server admi

In the process of learning the SIP protocol, we need to be clear about a concept, that is, the concept of SIP relay. In order to help you better understand this aspect, we use a comparison between Chinese and English translations to help you understand this aspect. The specific information is as follows: A sip Trunk is a logical connection between an ip pbx and a Service Provider's application servers that allows voice over IP traffic to be exchanged

The speed of network development is amazing. With the application of various network protocols, more and more devices can graft a variety of platforms to complete some of the settings that people need. Here we will discuss the working principles of dhcp relay. With the expansion of the network scale and the improvement of network complexity, the network configuration becomes more and more complex, and frequent computer location changes such as hosts o

When there are a large number of hosts in the LAN, if you set the IP address, default gateway,DNS server address and other network parameters, it is obviously a laborious and may not be pleasing method, then use DHCP to distribute the IP address, The ability to dynamically configure the network address parameters of each client greatly reduces the cost of management and maintenance. The following is an example of installing a DHCP server and a DHCP relay