AVE VSI-PRO operation manual Appendix D, RS-485 Networker

APPENDIX D RS-485 NETWORKER

RS-485 NETWORKER

The RS-485 Networker is designed to convert the RS-232 serial port output of the VSI-Pro to be a poll/select network. This allows all the transaction data to be collected by one computer for up to 64 VSI-Pros.

APPLICATION

Many users of the VSI-Pro want to capture all the transaction data from several units to one device. The RS-485 Networker allows all data from up to 64 VSI-Pros to be recorded on one PC or sent to one DVR. The user can then later search data history for evaluation. With remote software like PC Anywhere, a remote location could dial into many sites and review exception history and provide a value added service their existing customers.

THEORY

The VSI-Pro contains an internal data buffer of 24K bytes. The VSI-Pro can also be programmed for this buffer to hold all the on-screen data or just exceptions optionally containing Time/Date and other trigger text. The “handshaking” option in the VSI-Pro allows for external hardware handshaking for this output port to be controlled by the “RTS” input. When this hardware handshaking input is false, the data is saved to the internal buffer. When this input is true the data is sent out the serial port. The RS-485 Networker controls this handshaking signal to the VSI-Pro and when the networker is addressed by the host the data from the VSI-Pro is sent to the host. The data from each Networker is saved to a log file on the PC which can be read later as a data history from each VSI-Pro.

RS-485 NETWORK

Up to 64 RS-485 Networkers can be connected on one RS-485 2-wire network. A unique address for each RS-485 Networker is set by its internal dipswitch. The protocol is basically poll/select. The baud rate is set at 19.2K.

RS-485 to RS-232 CONVERTER

A standard PC or Laptop is used with the supplied software. The RS-485 to RS-232 Converter converts the PC or DVR RS-232 to RS-485. The handshaking signals of the PC control the direction of the RS-485 communications.

			RS-232
	Triport		Cable
		VSI-Pro 1	RS-485 Networker	RS-485
CASH REGISTER 1				Cable
			1
	Triport		RS-232
			Cable
		VSI-Pro “n”	RS-485 Networker “n”
CASH REGISTER “n”

Hydra

Controller

RS-232

Cable

RS-485 to RS-232

Converter

COM 1 (DB-9) COM 2 (DB-25)

DVR

MODEM

“n” means up to 64 Cash Registers / VSI-Pros / RS-485 Networkers can be connected on one RS-485 Network

Figure 1D: Connection Diagram for RS-485 Network

VSI-Pro VIDEO SERIAL INTERFACE

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