TODO: add connectors and pins from manufacturers such as NI, B&B, ADAM, etc. Volunteers? Many cable manufacturers can recommend a 120 Ω cable intended to work with RS-422 or RS-485. A 120 Ω resistor on a 100 Ω cable will dramatically reduce the ringing compared to no termination. The termination resistor should be equal to the characteristic impedance of the cable. A long 3-conductor cable intended for RS-232 can often be switched to half-duplex RS-485, allowing communication at higher speeds and at higher external noise levels than the same cable used with RS-232 signaling. RS485 will support 32 drivers and 32 receivers (we are talking about bi-directional - half duplex - multi-drop communications over a single or dual twisted pair cable !!). The 8-lines of U1’s Port RD (Pins 19-22 and 27-30) are the bi-directional I/O data bus connecting U1 to the SMINI’s 3 input ports and 6 output ports. When the latch output is low, Q1 is turned off and the load is de-activated.

Auto start models are available for simple engine applications such as pump sets and also for Diesel Generators (DG) where electrical parameters and load control are also available. In the event that the Mains is out of specification the Load is automatically disconnected, the generator is automatically started and the load transferred to the generator. The legends and folklore, not to mention the flat out wrong information that has grown around the line length and data rate limits inherent in RS-485 are truly astounding. The RS-232 standard includes secondary serial data circuits (secondary TX data, and secondary RX data), three clocks (timing elements) for synchronous serial data transfer, Signal Quality Detector, RS485 standard and more. Typically Telecom applications are more I/O intensive than standard controllers. A Compressor Controllers uses interstage temperature and pressures to efficiently control production of compressed air in multi stage compressors. An Auto Start controller is an enhances Manual controller which uses a digital input to control the Start / Stop of the engine. Ability to specify the parity, word size, and number of stop bits. An Engine Controller Unit (ECU) is an integrated electronic device, which controls start and stop sequencing for Diesel Engines. The EMS power meters are specifically designed for Diesel Generator operation and require 12/24 DC to operate.

A Power Meters monitors 1 or 3 phase AC power connections for Voltage, Current and Power Factor. It also monitors and display engine operating parameters (Oil Pressure, Engine Temperature, Battery Voltage, Speed etc). It calculates and displays the measured parameters and calculated active and reactive powers. The RO and DI terminals are the output of the receiver and the output of the driver respectively. D0 and D1 output the information to the serial port on the PC side. Again many thought that the UART protocol used in the serial port were part of the RS-485 standard, but the RS-485 standard contains even less of the OSI model layer one than RS-232 does. For example, one of the circuits is "AB". This is a example of point to point (one port communicates with one device). When two pair of wires are used for full-duplex communications, one pair is used for the interface generator (driver) to talk to the other device(s) on the RS-422 network, and the second pair is the interface receiver used to listen to an other device (not devices, since only one driver can be on this pair of wires) on the network.

Two STM32 development board, we use Waveshare Xnucleo-F103RB board (with STM32F103R chip) in this manual. Communication between two boards: connect the CANH and CANL to another one’s CANH and CANL of the CAN port separately. Connect the A and B to another one’s A and B of the RS485 port separately. Note: RS485 CAN Shield can only use a 3.3V power supply, UNO, Leonardo, and other Arduino cannot use the CAN function due to hardware limitations. Based on the standard Arduino interface design, it is compatible with development boards including UNO, Leonardo, NUCLEO, and XNUCLEO. It can’t be denied that the UART IBM selected for its implementation of the serial port is considered by many as the definition of RS-232, but these parts are not in the RS-232 standard. 3 of Xnucleo are Serial to USB ports as default. 8) are CAN's sending and receiving ports respectively as default. D14 and D15 are CAN's sending and receiving port respectively as default. You can choose UART1 or UART2 for the RS485 transceiver port by setting jumper 485 RXD/TXD JMP.