Chip Siemens SM 680 BUSDEC-H7988 Doc

[Bufere]

I am looking for the documentation of the hardware chip Siemens SM 680 BUSDEC-H7988 used in each card input and output of the S5 100U and S595U
also be inserted in each bus double standard connector.
I only realized that this is a shif register autoconfigurable, requires no additional components or quartz.
I would like to create custom cards privately.
Anyone can help me out, even indications sites.
thanks to all
Bufere