peb20560 Infineon Technologies Corporation, peb20560 Datasheet - Page 50

• Manufacturer Part Number: peb20560
• Description: Dsp Oriented Pbx Controller Doc
• Manufacturer: Infineon Technologies Corporation

PEB 20560
Functional Block Description
The PCM-interface reads periodically from the upstream (writes periodically to the
downstream) data memory (cyclical access), see Figure 2-1.
The CFI reads periodically the control memory and uses the extracted values as a
pointers to write to the upstream (read from the downstream) data memory (random
access). In the case of C/I- or signaling channel applications the corresponding data is
stored in the control memory. In order to select the application of choice, the control
memory provides a code portion.
The control memory is accessible via the µP-interface. In order to establish a connection
between CFI time-slot A and PCM-interface time-slot B, the B-pointer has to be loaded
into the control memory location A.
2.1.2.3.4
Pre-processed Channels, Layer-1 Support
The EPIC-1 supports the monitor/feature control and control/signaling channels
according to SLD- or IOM-2 interface protocol.
The monitor handler controls the data flow on the monitor/feature control channel either
with or without active handshake protocol. To reduce the dynamic load of the CPU a
16-byte transmit/receive FIFO is provided.
The signaling handler supports different schemes (D-channel +C/I-channel, 6-bit
signaling, 8-bit signaling).
In downstream direction the relevant content of the control memory is transmitted in the
appropriate CFI time-slot. In the case of centralized ISDN D-channel handling, a
16-kbit/s D-channel received at the PCM-interface is included.
In upstream direction the signaling handler monitors the received data. Upon a change
it generates an interrupt, the channel address is stored in the 9-byte deep C/I FIFO and
the actual value is stored in the control memory. In 6-bit and 8-bit signaling schemes a
double last look check is provided.
Semiconductor Group
2-4
2003-08