According to a few references I found.. the T7250C is nearly identical to the
DBRI chip found in sparcs.  According to the linux driver, the T7903 is also
very similar.

Crystal audio has full documentation for the 4215 on thier web page..  and
there is also the very limited tadpole documentation on the DBRI.

T7250C Enhanced User-Network Interface for ISDN and Proprietary Endpoints
Data Sheet (DS95-029ISDN)
http://www.lucent.com/micro/isdn/docs/DS97404.pdf

T7903
http://www.lucent.com/micro/isdn/docs/DS97161.pdf

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Tim Rightnour <root@garbled.net>
NetBSD: Free multi-architecture OS http://www.netbsd.org/
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