Who Uses 'Clock & Data' Format In Electronic Access Control?

One aspect of readers/credentials seldom covered is the 'Clock & Data' format. In the obscure world of credential communication formats, it is another semi-obsolete serial bus that is not very secure and is not often used, especially since the advent of the ethernet network. However, like Wiegand, many current and new readers support the format. My curiosity is: why?

Maybe 'Clock & Data' formats are used outside the US, or are common in certain verticals. Is the cabling different? Any insights you can share?

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*** *** ** *** ** ** ********** ***** * ******** had ** ******** **** ** *** ****** ****** ******* *** they **** ******* ******* ** **** *&*. * ***** *** any ***** ** ****** *********** **** *** ******* ******* ** the **** ****. *'* *******, *** *'* **** ******* **** knows *** ***/*** *&* ***** *****.

**** ***** ******* ******** *************. ** ** **** * ************* protocol **** *** ** ******** ****** ** ***********, ** ********** at *** ********** ***** ** ***** ** ****** ** *** switch ********. **** ** *** ****** ***** ***** *** **** that *** ***** ******* **?

********* ********* ******** *** *****, ****** "*****" *** "****".The **** **** ** **** ** **** *** *** ******
data ** *** *****. This is accomplished by changing the state of the voltage on the line. Five (+5V) volts is
********** ** * "*" ***, *** **** (**) ** ***** to * "*" ***. ** ******** *** ***** **** **** to ***, *** *****
****** **** **** *** ******** ****** ** *** **** ** sent ** *** *****.

*** ****** **** **** *** *****/**** ********* ** **** ** tell *** ***** **** ** ****** *** **** ****.Each
time * *** ** **** ** **** **** *** **** ****, * ***** ** **** **** *** ***** ****, *********** *** ***** ** ****
a "******" ** *** **** **** *** ****** **** **** ***.

******* ********* ** ************* *********. ** **** *** ******** **** lines ** **** **** ** *** ***** ** ********* ** a ***** ****** ****. **** *** ****** "**** *" *** "Data *". ** *** ***** ******, **** * ** **** to ***** *** "*" **** ** *** *****, ***

*** **** * **** ******* *** "*" ****. *** **** data *****, *** ******* ** ******** **** (+**).When * *** ** *****
signaled, *** ******* ** *** *********** **** ** ****** ** **** (**) *****. Wiegand allowed very long cable runs. From wikipedia:

******* **** ** ***-****** ********, * ************* ***** ** ******, iron, *** ********. *********, *** **** ** ***** ********. ** this ***** *** ***** ** "****" ** *** ******** *****; that **, ** ** ********* ** ******* *** ** ******** field ***** **** ****** ************** **** *** *****, *** *** metal ******* **** * **** ***** ******** ***** **** *** external ***** ** *******.

****** ***********, ** **** *** **** *** ****** ******** **********, it ** ********* ** * ****** ** ******** *** ********** operations ** ****-**** *** ******* ***** ** *** **** ***** retaining * **** **** ****** *** ****, *** **** *** wire ** ****. *** ****** ** **** *** ******** ********** of *** ******* ***** ** **** ****** **** **** ** the ***** ****. **** **** ********** ***** ***** **** ****** an ******** ******** ***** **** **** *** *****'* ******** ****** is *******.

*** **** *** ******** * **** ***** ******** **********: ** a ****** ** ******* **** *** ****, *** **** ********** outer ***** ******** *** ******** ***** **** *** ***** **** core ***** *** ******** ********* ** *******, ********* *** ****** wire — **** *** ***** ***** *** ***** **** — rapidly ******** ************* ********. **** ********** ****** ** * *** microseconds, *** ** ****** *** ******* ******.

*** ***** ** *** ******* ****** ** **** *** ********** speed ** ************ **** **** * *********** ******* *** ** output **** * **** ***** * *******-**** ****. ******* *** voltage ******* ** * ******** ******** ***** ** ************ ** the **** ** ****** ** *** *****, * *******-**** **** can ******** *** ****** ******* ** * ******** ***** ****** by ******* ****** ** ********* ** ******** ** * ******* coil **** * ***-******* ****. **** ****** ******* *** ****** be ******** **************, *** **** ******** **** *** **** ************* threshold ** *** ******** ***** *********, ****** *** ******* ****** useful *** ********** *******. **** *** ******* **** *** ******* magnetization, ** **** ****** **** ************* ***** ******* ** *** other *********. ******* *** ********** **** *** *** ******* ****** must **** **** ********* **** *******.

*******, (*) ******** *** **** ***** ****, (*) ******* *** Wiegand ******** ** * **** ** ** ************* *** ******** into *** ****. *** **** ****** ** ************ **** * mag ****** ****. ******* *** ******* ****'* ********* ******* *** amount ** **** ** ** ****. **** ****** ******* ****** manufacturers ******* ******* **********, *** **** ******* **** *** *********** of **** * **** *** **** ***** (*-***) *** ** bits *** **** ******* (*-*****), ** **** ******** ***** *** formats **** ******* ********** ** ***** ******* *** ******* *** parity ******** ***** ******* **** *** *********** *****.

************* *** * ************ ****** **** *** **** ** *** door ** *** ** **** *** ******** ******* ******* *** convert **** ** ***** **** *** *** *****. *** ****** cards *** *** ******* **** ******. ******* ****** **** ******* per **** ***. *** ****** ***** ** ******* ** ***** data. ** **** **** **** ** **** ** * ****** booster ** ********* **** ****.