72
MASTER COMMUNICATION PROTOCOL

OPERATION

The VSI-Pro Max or Hydra/Regcom/Vnetworker/Networker use a bi-directional, 2-wire RS-485 databus to
communicate. A VSI-Pro Max can be a Slave or a Master. A Regcom, Vnetworker or Networker are used to convert
the VSI-Pro, ECR Cards or Adapters to be slaves. The Hydra is a “Master” device and only one unit required for up
to 16 Slaves. Only one master device can exist on a single network. When the VSI-Pro Max is used to connect to a
register that uses the emulate mode then it can not be a Master. However the VSI-Pro Max can connect to a normal
register in tap mode and still be configurable as a master or slave.
The master device controls the flow of data by polling each of the slaves in turn. When polled, a slave device will
either respond with a ‘‘No Data’’ code to say it has no data to send, or it will begin sending data from its buffer.
The Hydra or VSI-Pro Max can support many manufactures of DVR for direct storage of the transaction data on the
DVR as a file rather than just inserting in the video image for recording. It also supports the VSI-ADD (VSI Addressable)
format which allows multiple VSI-Pros or VSI-Pro Max to be mounted in a convenient rack and connected to a
Master for display of cash register data remotely. See Figure below.

HYDRA COMPAT ABILITY LIST

DVR
< Norbain Columbus
< GE StoreSafe
< Kalatel StoreSafe
< NOVAR VP
< Dallmeier
< Appro
< Pinetron
Figure 134: DS-20-OF VSI-Pro Max PCB Rack using VSI-ADD protocol
MASTER / HYDRA APPENDIX M
VSI-Pro Max POS / Cash Register Interface
Pair 3
1
2 3
4
5
6
7
8
Pair 2
Pair 4
Pair 1
T568B
The Network Port of a VSI-Pro Max, Regcom or Hydra use an RJ45 connector. Each unit has two RJ45s and the
Networking signals Pins 4&5 are in parallel. However in the VSI-Pro Max all pins are wired in parallel but the
Regcom or Hydra are not. The useage of an RJ45 connector allows the installer to use either RJ11, RJ12 or RJ45
connectors since all support the center two pins of the connector which are the only pins used.
Figure 133 : RJ45 Network Connector Pin Out