Door access card reader and BS2p

poguemomhoin

Hi,

I would like to read 125kHz Wiegand cards to get the user ID. I have a BS2p available, but from reading the forums I see that the BS2 is not fast enough to read the Wiegand output from this type of card reader.
The card reader I have does not have an RS232 output, but it can output in clock/data format, which is a synchronous form of serial communication, where the clock as well as the data is supplied from the card reader. This means I can't use the SHIFTIN command, as the BS2 provides the clock.

Anyone know of another way I can get the info from the card reader into the stamp?

davejames

...just thinking out loud - how about the SERIN command?

Is the mentioned 125kHz the frequency of data coming from the Wiegand card?

poguemomhoin

Serin is asynchronous, so there is no clock info. 125kHz relates to the communication between the card, and the card reader, rather than from the card reader to the host.
Keep thinking out loud though!

Mike Green

You're going to need some significant amount of hardware to tie these two together. You could use a serial to parallel shift register to hold the output of the card reader, then either another shift register (parallel to serial) to let the Stamp clock the data in or some other control logic so the Stamp can take over the shift register from the card reader to clock the data in. The details would depend on the details of the card reader. You could also use some kind of 8-pin microcontroller to do the serial to serial conversion. You'd have to do the programming.