B&B Electronics 232D4SS8 manual Smart Switch Operation, Smart Switch Mode

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Another option available on the 232D4SS8 is the slave ports set up as RS-422 ports. This means that the driver and receiver will be enabled all the time. RS-422 allows point-to-point operation or up to 10 receive only units up to 4000 feet on two pair of lines.

Smart Switch Operation

The 232D4SS8 has two modes in which it can select ports, smart switch, and smart switch/port combiner.

Smart Switch Mode

Position 6 of SW1 must be in the off position to enable this mode. Refer to Figure 2 and Table 1. The Smart Switch is a listen only device. It constantly monitors the serial data received on the Master port for a command control string. A command can switch on or switch off any desired port. The command control string can be configured as a three-character command or a four-character command. In this mode Port "A" will be selected at power up.

Three Character Command String

The first character is user defined by setting SW2, an eight- position DIP switch. SW2 is programmed at the factory to the ASCII character STX (decimal 2). The second character represents the hexadecimal address of the Smart Switch where the desired port is located. The address for the 232D4SS8 is always zero (0). The third character is the ASCII upper case letter that represents the desired port. Letters "A", "B", "C", "D", "E", "F", "G" or "H" (decimal 65, 66, 67, 68, 69, 70, 71, or 72 respectively) are used to select ports on the 232D4SS8.

Example 1: To turn on port E of the 232D4SS8 (address zero) with ASCII STX (2 decimal) character set as the user defined character.

Send to the Master Port: STX 0 E

(2 48 69 decimal)

When you are done with a port you can either select a new one directly or turn off the selected port and then turn on the next one. It is recommended that the selected port be turned off before selecting the next port. For this reason, if port A is currently selected and a command is sent to select port E, the command characters (STX 0

E)will pass through to the port A device and because characters "0" and "E" are printable they may appear on that device.

Documentation Number 232D4SS84502 Manual

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B&B Electronics Mfg Co – 707 Dayton Rd - PO Box 1040 - Ottawa IL 61350 - Ph 815-433-5100 - Fax 815-433-5104 B&B Electronics Ltd – Westlink Comm. Pk – Oranmore, Galway, Ireland – Ph +353 91-792444 – Fax +353 91-792445

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Contents Port Smart Switch CE Table of Contents Introduction HardwareSwitching Baud Rate From 300 to 38.4 Kbps Front ViewRear View Serial Data Configuration Simplified Functional Diagram ChecklistCommunication & Configuration Switch DIP Switch Setting Port ConfigurationMaster Port Printed Circuit Board Outline Master Port DCE/DTE Jumpers Description Port DCE Master Port Chart Signal Direction Pin #DTE Master Port Chart Signal Direction Pin # Description Clear to Send Input Data Set Ready Input Signal Ground Carrier DetectRS-232 Configuration Request to Send OutputRS-422/485 Ports a H Signal Pin # Description Direction Simplified RS-232 Schematic RS-422/485 Slave Port OptionRS-422/RS-485 Mode Simplified RS-422/485 Schematic4800 6001200 2400Smart Switch Operation Smart Switch ModeThree Character Command String Four Character Command String Programming the User Defined Character Smart Switch/Port Combiner Mode SW2 Weight Chart DIP SwitchPort Select Test Binary File TransferSoftware 232D4SS8 UsersMethod One Method Two Smart Switch SetupDefault Values Description Default ValueSelecting Ports Uninstalling Windows Smart Switch Selector ProgramDecimal to HEX to Ascii Conversion Table Appendix a Ascii Character CodesAppendix B Cable Charts Master Port DTE Chart 3. Modem DB25 Connector to Master PortChart 4. DCE Device w/DB25 Connector to Ports a H DTE Async Modem 232D4SS8Chart 6. IBM PC DB9 Connector to Ports a H DTE Chart 5. IBM PC DB25 Connector to Ports a H DTEChart 8. IBM PC DB9 Connector to Ports a H DTE Chart 7. IBM PC DB25 Connector to Ports a H DTEPorts a H Declaration of Conformity Appendix C Declaration of Conformity