Communication

Both Wiegand and Serial protocols are provided by the reader, accessible through the reader harness. It is up to the installer to decide which to use for a specific location.

Serial

ASCII data is sent through serial at 9600 baud rate by default. This is the preferred method of receiving data from a TransCore reader and is used by PiTransCore provided by the transcore library.

Data sent through the serial port and directly processed by a connected machine is easy to parse directly. Here is what the data looks like:

Text	Description
#	Start of data
ABC	Tag facility
12345678	Tag ID
...	End of data, followed by newline \n

A typical serial console session after scanning various tags would look something like this:

#DFW12345678...
#DFW87654321...
#DFW42342343...

Converting ASCII to Wiegand

Should this data need to be converted to Wiegand for older access controllers, an additional adapter board can be used to convert the incoming ASCII data to Wiegand. Converting the serial data to Wiegand is better than directly using the TransCore reader's Wiegand output as you gain control over the format to use, such as the 34-bit Wiegand format. To do this, boards such as the Cypress CVX-1468-A come into play and provide a better alternative for using TransCore readers with legacy hardware and software.

This setup is common with legacy Linear AM3 commercial installations.

Warning

We advise against using Wiegand in new designs and systems. Wiegand is not encrypted and, as such, can be read and exfiltrated with an attack known as MITM (man-in-the-middle).

Lossy conversions in Wiegand bit formats can result in more than one tag being granted access to a facility.

Wiegand

For compatibility with older access controllers, Wiegand output is provided by the device itself. However, due to the reader only supporting the 26-bit Wiegand protocol, it will only read up to a 16-bit tag ID. This means that even when one needs to receive Wiegand data from the reader, it cannot be directly sent due to this limitation of the number of possible tag numbers.

Note

Wiegand is not supported by the transcore library.