My project was many years ago, but I will have a look in the files to see if I can some of the code.
In my case, I was able to configure the card reader for rs-232 serial output, which was necessary to get the BS2sx to read the data. Can you confirm that your device can be set to rs-232?
I have not yet been able to find the notes on my project. But, I did find the following on Wikipedia which refreshed my memory a bit.
"The Wiegand interface uses three wires, one of which is a common ground and two of which are data transmission wires usually called DATA0 and DATA1, alternately labeled 'D0' and 'D1' or 'Data Low' and 'Data High'. When no data is being sent both DATA0 and DATA1 are pulled up to the 'high' voltage level - usually +5 VDC. When a 0 is sent the DATA0 wire is pulled to a low voltage while the DATA1 wire stays at a high voltage. When a 1 is sent the DATA1 wire is pulled to a low voltage while DATA0 stays at a high voltage.
A high voltage level of +5VDC is used to accommodate for long cable runs (most reader manufacturers publish a maximum of 500 feet) from door readers to the associated access control panel typically located in a secure closet."
The card reader I used was able to be switched to RS-232 so the only challenging part was to decode the 26 bits. The BS2sx allowed the long string of digits to be captured in the scratchpad RAM and then parsed.
dioher
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I don't think the BS1 has the power to deal with the Weigand format. I had to use a BS2sx to get sufficient speed and available memory.
Cheers,
Thank you.
In my case, I was able to configure the card reader for rs-232 serial output, which was necessary to get the BS2sx to read the data. Can you confirm that your device can be set to rs-232?
Cheers,
"The Wiegand interface uses three wires, one of which is a common ground and two of which are data transmission wires usually called DATA0 and DATA1, alternately labeled 'D0' and 'D1' or 'Data Low' and 'Data High'. When no data is being sent both DATA0 and DATA1 are pulled up to the 'high' voltage level - usually +5 VDC. When a 0 is sent the DATA0 wire is pulled to a low voltage while the DATA1 wire stays at a high voltage. When a 1 is sent the DATA1 wire is pulled to a low voltage while DATA0 stays at a high voltage.
A high voltage level of +5VDC is used to accommodate for long cable runs (most reader manufacturers publish a maximum of 500 feet) from door readers to the associated access control panel typically located in a secure closet."
The card reader I used was able to be switched to RS-232 so the only challenging part was to decode the 26 bits. The BS2sx allowed the long string of digits to be captured in the scratchpad RAM and then parsed.
I will keep looking.
http://forums.parallax.com/showthread.php?83367-Wiegand-Input&highlight=stamptrol
There is some discussion on an SX/B program which should be adapatable to a Stamp.
Cheers,