Hi Kenneth,

I posted a replay last week but it was not published in the forum ( I don’t know way).
I answer again.

1.
{{{. Can a general 8052 without any Programmable counter array interface the EM4095? Since I notice from EM4095's Datasheet that "the used uController should be able to measure pulse widths and pulse periods and to switch to the inverted measuring edge (falling/falling<->rising/rising) while reading."
But, I don't understand yet what "being able to switch to the inverted measuring edge (falling/falling<->rising/rising) while reading." mean. }}}

Yes, you can. Actually I used an AT89C2051 to do this job. It is an old project ( 7-8 years old I thing ) so I forgot details. The Manchester code decoding and the row-column parity calculation “eat” about 200 bytes. The remainder flash memory was used for an EEROM database management and PC communication.
There is a little trick regarding the 180deg phase incertitude introduced by Manchester scheme but it is easy to manage. I remember I wrote several decoding algorithms with or without interrupt. The last version used to decode the card in the background and other tasks in timer and uart interrupt routines.
An ordinary 8051 like processor running at al least 6 MHz is enough to do all the job but I used an 11.059 MHz clock for comm purposes.

2.

{{{{Is there any special difficulty using a 8052 to interface the EM4095, which may not be the case if another uC was used?}}}

No. I ported the software to an AVR atmega8 ( for some commercial reasons) and I found the software to be twice longer that for at89c2051; I thing this is because of the bit instruction facilities of the 8051 core and the automatic calculation of the parity in ACC.

So I strongly recommend 8051 core for such task.


Cristian Ceausescu