PEB2085 SIEMENS [Siemens Semiconductor Group], PEB2085 Datasheet - Page 28

• Manufacturer Part Number: PEB2085
• Description: ISDN SubscribernAccess Controller
• Manufacturer: SIEMENS [Siemens Semiconductor Group]

Features
Line Card Applications
An example of the use of the ISAC-S on an ISDN PABX line card (decentralized architecture)
is shown in figure 8.
The ISAC-S is connected to an Extended PCM Interface Controller (EPIC PEB 2055) via an
IOM interface.
This interface carries the control and data for up to eight subscribers using time division
multiplexing. The ISAC-S’s are connected in parallel on the IOM (IDP0 output; IDP1, DCL,
FSC1/2 as inputs), one ISAC-S per subscriber.
The EPIC performs dynamic B- and D-channel assignment on the PCM highways. Since this
component supports four IOM interfaces, up to 32 subscribers may be accommodated.
1.4.2
Microprocessor Environment
The ISAC-S is especially suitable for cost-sensitive applications with single-chip
microcontrollers (e.g. 8048, 8031, 8051). However, due to its programmable micro- processor
interface and non-critical bus timing, it fits perfectly into almost any 8-bit microprocessor
system environment. The microcontroller interface can be selected to be either of the Motorola
type (with control signals CS, R
W, DS) of the Siemens/Intel non-multiplexed bus type (with
/
control signals CS, WR, RD) or of the Siemens/Intel multiplexed address/data bus type (CS,
WR, RD, ALE).
An example how to connect the ISAC-S to a Siemens/Intel microcontroller is shown in figure 9.
Semiconductor Group
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