Using a VTAP Wiegand reader for access control

A VTAP100 Wiegand reader (VTAP100-PAC-W) can interface directly with a Wiegand controller, as a door or turnstile reader in an access control system.

Many customers want to replace an existing access control reader with a VTAP reader, in order to add the capability to use NFC wallet passes in addition to using an existing population of cards or tags. This may be during a temporary migration phase in the roll out of mobile wallet passes, or to create a permanent hybrid solution, able to accept both cards/tags and NFC mobile passes.

There are several steps in adding a VTAP reader to an access control system with a Wiegand interface:

1. Check your access control system data requirement:

   Check the format of data expected by your access control system from existing cards or tags, if any. Your access control system may already accept credentials from more than one type of card or tag. For each type of card or tag, find out:

   • Does your system use the card UID or block data?

   • How many bits of data are transferred?

   • Are digits used by the access control system decimal or hexadecimal?

   • In which order are the bytes read?

   • Is there any site or facility code?

   • Are there any checksum bits?

   A good understanding of your access control system in this step, will make it much easier later to achieve a configuration where interchangeable, equivalent data can be extracted from both mobile passes and cards/tags.

2. Mobile pass design:

   Design a mobile pass containing the type of data required by your access control system. If this will be used in an existing or hybrid access control system, ensure the pass design includes either the ASCII, hex or decimal version of the binary data you store on existing cards/tags.

3. VTAP reader configuration:

   Connect the VTAP reader to a PC using a USB cable.

   Edit the VTAP config.txt file to Send pass payload over a Wiegand interface, in the format expected.

   If cards/tags will be presented to the VTAP reader in addition to mobile passes, don't forget to set up the additional configuration needed to Send UID or block data from a card/tag over Wiegand.

   There may then be some fine tuning of that configuration required, to ensure you Format pass and card/tag data to match over Wiegand so that mobile passes and cards/tags are truly equivalent in your system.

   You may also need to delay startup of the Wiegand interface by a number of milliseconds to allow the power supply to stabilise. We recommend that you use a value such as 5000ms (setting StartupDelayMS=5000 in  config.txt) when using an external power supply, to prevent possible file system corruption during installation if VTAP could be wired up to a live external power supply.

4. Wire the VTAP reader Wiegand interface:

   Safely remove the VTAP reader from the PC and connect the VTAP to a controller to your access control system following the Wiegand wiring (for model VTAP100-PAC-W only).

   Depending on the type of controller you are using, you may need to use controller configuration software to identify and link the reader.