RS232/RS485 interface cable for Schneider PLC programming,3 meters,with master/slave switch,used for programming communication or other communication such as MODBUS. TSX08PRG connect with computer and communicate with Schneider PLC need to install Uni-Telway or MODBUS driver to at first, for using the corresponding various PLC programming software, to realize the operations as upload, download, control and communications. Then the programming software can be used to complete the normal communication with the PLC. These drivers are usually included in the programming software on CD-ROM And for the specific installation steps, please refer to the instruction files on the CD-ROM drivers, and details are not necessarily listed here. If more than one slave tried to drive the transmit line simultaneously, their serial drivers would fight with each other for control of the bus. You can use one or both of the PDQ Board’s RS485 links to create such a multi-drop serial network. This allows for basic error detection, in that if noise on the transmission line causes one bit to be received incorrectly, either received as a '0' when transmitted as a '1' or vice-versa, the error would be detected due to the count of '1' bits in the byte being odd when it is expected to be even, or vice-versa depending on the parity checking settings.
While these signals provide a data path, they do not provide hardware handshaking that allows the two communicating parties to let each other know when they are ready to send or receive data. While running this program, the parity settings of Mosaic Terminal may be adjusted, and in each case the message that matches current settings will appear clearly while the other messages will appear garbled. In this case, cable connections may be made to Serial 2 on either the 10-pin PDQ Board Serial Communications Header, or the Docking Panel’s 10-pin right-angle Serial Header, or the Docking Panel’s Serial2 DB-9 Connector. To provide a convenient means of attaching two grounds to the serial cable, there are several pins (labeled DGND) on the communications connector that are connected to the controller’s ground plane. In this case, cable connections may be made to Serial 1 at pins 5 and 6 of the PDQ Board’s 10-pin Serial Header , or pins 5 and 6 of the Docking Panel’s 10-pin right-angle Serial Header. Bias termination - Using resistive termination decreases noise immunity, particularly if the cable is loaded with many devices. In fact, you have been using it all along as you worked through the examples in this document.
If PT is set, all transmitted bytes with a parity bit will have an odd number of total '1' bits. If PT is cleared, then all transmitted bytes with a parity bit will have an even number of total '1' bits. RS485Receive() to wait for any pending character transmission to complete, then disable the transmitter, and then execute a routine such as Key() to listen to the communications on the serial bus. The BAUD routine described at the start of this subsection configures the baud rate of each of the Serial1 and Serial2 channels. The Serial1 and Serial2 ports are is supported by the HCS12's dual on-chip hardware UARTs, and do not require interrupts to work properly. Using the primary Serial1 port is easy. Because we chose the default baud rate (which the terminal is presumably already set for), you can simply move the serial cable from the Serial Port 1 connector to the Serial Port 2 connector on the Docking Panel to complete the change to the new port. The PDQ Board’s transmit data signal /TxD1 (pin 2 on the 9-pin serial connector) is connected to the terminal’s receive data signal /RxD (pin 2 on its 9-pin connector). For seven data bits with a parity bit, M would be cleared (equal to zero), and PE would be set in order to make the most-significant bit of a normal eight-bit byte be used by the serial port as a parity bit.
Before running the program, let’s switch to the secondary serial port. Because all of the serial I/O routines on the PDQ Board are revectorable, it is very easy to change the serial port in use without modifying any high level code. In that case, when using very long cables you can improve noise immunity and assure a valid idle level when the transceiver is not active by installing bias resistors. Thus in the table, /RTS1 is connected to /CTS1, and /DSR1 is connected to /DTR1 and /DCD1 onboard the PDQ Board using zero ohm shorting resistors. The mating 10-pin connectors that join the H6 header of the PDQ Board to the H4 header of the Docking Panel are typically not accessed directly, and are not discussed in detail here. Once the project is open, click Build→ Build, and after the compilation is done, enter the Mosaic Terminal by clicking Tools→ Mosaic Terminal and use the Send File menu item to send GETSTART.DLF to the PDQ Board.
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