Clear-Com 4000 series II, Technical Manual

Page: 94 / 134

Technical Manual Issue 2.1 4000 Digital Series
II
Page 70 STA0381
4.1.3 PDE4641 60-way SIMM card
Figure 64 - PDE4641 60-way SIMM Card
This sub-assembly is a 60 way SIMM card which is uniquely programmed with a PROM(U1) for
identification of allowed features by the PDE4642 processor card.
It is fitted to the rear of PDE4629/4639 backplanes.
4.2 Front Cards
The digital and control processing for the system is carried out by a number of electronic cards. A brief
description of each of the cards follows. Specific configuration (quantities, etc. is system-dependent).
4.2.1 PDE 3601A - Digital Matrix Card (DMC)
Figure 65 - PDE3601A Digital Matrix Card
The function of the DMC is to route matrix output signals by combining inputs with variable gains applied
at each crosspoint. The mapping of inputs to outputs, and the respective crosspoint gains, are controlled
via the Control bus.
Each card carries four `routers' which are identical microprogrammable routing and mixing processors.
Each has its own Audio Input RAM, Routing (microprogram) RAM, Gain RAM, MAC (Multiplier-
ACcumulator) and control circuits; however they all share a Common Output Conditioner (shift-limiter)