Old text backup: The address and baud rate setting method of single chip microcomputer node in industrial network

In industrial applications there are many single-chip unit network applications, whether it is 485 network, can network or any other network, will be related to the node address setup problem, the following to explore several ways to set the address:

1. Hardware settings

On the single-chip microcomputer circuit board, plus a dial-code switch, the binary switch state to indicate the address value, the dial switch by the single-chip microcomputer I/O to detect, single-chip microcomputer in each power to detect a code switch state, set the address of this node, can also be periodic such as 500mS to check the status of a switch, Dynamically set the address of this node, it is recommended to use the method of power-up detection, because the method is simple and practical, can be initialized after detection of some resources related to the address, if the use of dynamic detection method, not only occupy the system resources and address-related resources each time to re-initialize, which is very cumbersome and not conducive to system design.

1. Software Settings

Using the method of pure software, when the node factory, the initial address of the preset node, the node is attached to the Internet, the host computer through the network Communication command to set the address of the node, and then the node will store the address information in nonvolatile memory, each time the system restarts, the program must read the address information stored therein. This method requires the node to have non-volatile memory to read and write, and in the network can only have one node address as the initial address, otherwise it will cause network access chaos or even network crashes.

1. Hardware and software combination settings
   1. Multi-bit dial switch + software setup

   You can set the address through the dial switch, but also through the software settings, the problem of the two settings methods to listen to WHO, the solution is that when the dial switch set to the specified state (such as all 0), can be changed by the software node address, the node at each power-up to detect the dialing switch state, if it is the state, Go to non-volatile memory to find the node address information changed by the software, as the node address, if the power is detected in the other state then the address code represented by the corresponding State is the address of the node.

   1. One Toggle switch + software setup

   This method is actually belong to the software address setting mode, plus a toggle switch to the node address to switch back to the initial value, to avoid the host computer lost the node has been set to the address and cannot find the phenomenon of the node, and the bit switch to restore the default (factory) settings, and the software can be combined with the node address, Baud rate, the default configuration all revert to predefined values, the benefits of self-realization.

The baud rate is set up in the same way as the node address, but note that the baud rate change is the whole network of all nodes, more than the setting of the address.

Several ways have advantages and disadvantages, the specific application of which method should be based on the system design requirements and resources integrated consideration.

(2007.1.30)

Old text backup: The address and baud rate setting method of single chip microcomputer node in industrial network