PEB20534H-10V2.1 Infineon Technologies, PEB20534H-10V2.1 Datasheet - Page 128

• Manufacturer Part Number: PEB20534H-10V2.1
• Description: Communication Controller 208-Pin FQFP
• Manufacturer: Infineon Technologies

7
7.1
The Serial Communication Controller (SCC) distinguishes itself from other
communication controllers by its advanced characteristics. The most important are:
– Support of HDLC/SDLC, ASYNC, BISYNC/MONOSYNC, and point-to-point protocols
– Support of layer-2 functions (HDLC mode)
– In a special operating mode (auto-mode), the SCC processes the information transfer
– Extended support of different link configurations
– Telecom specific features
Data Sheet
(PPP).
In addition to those bit-oriented functions commonly supported by HDLC controllers,
such as bit stuffing, CRC check, flag and address recognition, the SCC provides a
high degree of procedural support.
and the procedure handshaking (I- and S-frames of HDLC protocol) autonomously.
The only restriction is that the window size (= number of outstanding unacknowledged
frames) is limited to 1, which is sufficient for many applications. The communication
procedures are mainly processed between the communication controllers and not
between the attached hosts. Thus the dynamic load on the host and the software
expense is greatly reduced.
The host is informed about the status of the procedure and has mainly to manage the
interrupt service. Receive and transmit data are managed by the on chip DMAC
autonomously. In order to maintain cost effectiveness and flexibility, the handling of
unnumbered (U) frames, and special functions such as error recovery in case of
protocol errors, are not implemented in hardware and must be done by the user’s
software.
Besides the point-to-point configurations, the SCC allows the implementation of point-
to-multipoint or multi-master configurations without additional hardware or software
expense.
In point-to-multipoint configurations, the SCC can be used as a master or as a slave
station. Even when working as slave station, the SCC can initiate the transmission of
data at any time. An internal function block provides means of idle and collision
detection and collision resolution, which are necessary if several stations start
transmitting simultaneously. Thus, a multi-master configuration is also possible.
In a special operating mode, the SCC can transmit or receive data packets in one of
up to 128 time-slots of programmable width (clock mode 5). Furthermore, the SCC
can transmit or receive variable data portions within a defined window of one or more
clock cycles in conjunction with an external strobe signal (clock mode 1). These
features make the SCC suitable for applications using time division multiplex
methods, such as time-slot oriented PCM systems or systems designed for packet
switching.
Serial Communication Controller (SCC) Cores
General
Serial Communication Controller (SCC) Cores
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PEB 20534
PEF 20534
2000-05-30