The SR-4 C/E Serial Network Controller.

Each controller can connect a serial path between one computer port and any combination of four motion systems. In addition, up to sixteen controllers can be "daisy-chained" together with simple pin-to-pin DB-9 serial cables. Power for each controller is obtained from the motion systems through the serial cables.

During operation, a three byte address is prefixed to a motion control command string. When the controller receives the address, a serial path is connected to the addressed motion system by a 1 to 4 serial data multiplexer. The motion command is passed to the motion system. The command terminator character (carriage return) also resets the multiplexer. Each command string must start with the controller address. The controller address compares to the setting of the controller switches. The multiplex code selects any combination of the four output paths to the motion system. In general, one system is selected at a time for setup commands and then all systems are directed to execute (Go) simultaneously. When requesting information from a system, only one can be selected.

When a motion system is preforming an operation, the CTS or Busy signal is input to the controller's status register. To monitor the busy status of the motion systems, a Read address, again consisting of three bytes, is sent to the controller. The first byte is the mode (Read); the second is the ID number; the last is always F HEX. The controller will return an ASCII character equal to a binary number. The first four binary bits are fixed at 4 HEX. The second four indicate the status of the four systems.

The host to controller serial ports are wired with standard RS-232 DB-9s connectors. Each controller has two, loop-in and loop out, communication ports. The first goes to the control computer and the second to the next controller in the daisy-chain. The last controller's second connector is terminated with a turn-around plug. The four motion system connectors are DB-9p.

The SR4 operates in RS-232 format using ASCII character mode and will Auto-Baud from 300 to 57K baud. Auto-Baud devices determine the baud rate automatically from two carriage returns sent during initialization of the system. Parity is none, 8 data bits, and 1 stop bit.

All MOTION GROUP (Electronic Products) motion systems connect to the SR4. The SID (Single Independent Drive) system supports up to four independent axes per controller with a maximum of 64 channels. With the MMC - 2S / 4S / 8S (Multiple Motor Controller) multiplex systems, up to 128 / 256 / 512 axes can be controlled from one serial port. >