PEB3264FV1.4 Datasheet, PDF (60/374 Pages) Infineon Technologies AG – Dual Channel Subscriber Line Interface Concept

DuSLIC
Functional Description
DuSLIC-E/-E2/-P FSK Generation
Different countries use different standards to send Caller ID information.
The DuSLIC-E/-E2/-P chip set is compatible with the widely used Bellcore GR-30-
CORE, British Telecom (BT) SIN227, SIN242, and the UK Cable Communications
Association (CCA) specification TW/P&E/312 standards. Continuous phase binary
Frequency Shift Keying (FSK) modulation is used for coding that is compatible with
BELL 202 (see Table 7) and ITU-T V.23, the most common standards. The SLICOFI-2
can be easily adapted to these requirements by programming via the microcontroller
interface. Coefficient sets are provided for the most common standards.
Table 7
FSK Modulation Characteristics
Characteristic
ITU-T V.23
Bell 202
Mark (Logic 1)
1300 ± 3 Hz
1200 ± 3 Hz
Space (Logic 0)
2100 ± 3 Hz
2200 ± 3 Hz
Modulation
FSK
Transmission rate
1200 ± 6 baud
Data format
Serial binary asynchronous
The Caller ID data of the calling party can be transferred via the microcontroller interface
into a SLICOFI-2 buffer register. The SLICOFI-2 will start sending the FSK signal when
the CIS-EN bit is set and the CID-data buffer is filled up to CIS-BRS plus 1 byte. The data
transfer into the buffer register is handled by a SLICOFI-2 interrupt signal. Caller data is
transferred from the buffer via the interface pins to the SLIC-E/-E2/-P and is fed to the
Tip and Ring wires. The Caller ID data bytes from the CID-data buffer are sent with the
Least Significant Bit (LSB) first.
DuSLIC-E/-E2/-P offers two different levels of framing:
• A basic low-level framing mode
All the data necessary to implement the FSK data stream—including channel
seizure, mark sequence, and framing for the data packet or checksum—must be
configured by firmware. SLICOFI-2 transmits the data stream in the same order in
which the data is written to the buffer register.
• A high-level framing mode
The number of channel seizure and mark bits can be programmed and are
automatically sent by the DuSLIC-E/-E2/-P. Only the data packet information must
be written into the CID buffer. Start and stop bits are automatically inserted by the
SLICOFI-2.
The example below shows the signaling of a CID on-hook data transmission in
accordance with Bellcore specifications. The Caller ID information applied on Tip and
Ring is sent during the period between the first and second ring burst.
Preliminary Data Sheet
60
DS3, 2003-07-11