> >Questions: > >Is there a demand anywhere in the worldwide market for multi-drop >capability at this type of PBX/TE--NT1 node? In the US? In Europe? In >Japan? >
I know a little bit about Europe concerning this matter. - In Germany, you can often see PBX systems which have a bus configuration on, at least one, of their T ports (PBX - NT1). This is often used as emergency application (emergency phone or data adapters). Even if there is no requirements as I know so far, it is often used as an additional sales feature of PBX manufacturers. - In Spain, this is often used in the same manner than in Germany. But the Spain PTT, Telefonica, requires bus mode for the ISDN-PBXs, which they have in their sales program. Many banks in Spain need this application for emergency X.25 connections over ISDN. And banks are so far very important ISDN-PBX costumers in Spain. >Do you know of any PBX manufacturers who provide this capability? - There are different manufacturer, like SIEMENS (HiCom) and ASCOM (Ascotel). - As far as I know the only IC supplier, which has a chip solution for bus mode on the T interface is Siemens. The part is called ISAC-S PEB2086 and supports TE, LT-S and LT-T modes. There should be a data sheet on the web. (You should use the most recent version V2.3, since the older ones have a bug in the D-channel collision detection of the LT-T mode.)
