PSB7238 SIEMENS [Siemens Semiconductor Group], PSB7238 Datasheet - Page 61

• Manufacturer Part Number: PSB7238
• Description: Joint Audio Decoder-Encoder - Multimode
• Manufacturer: SIEMENS [Siemens Semiconductor Group]

In the rest of this paragraph, for the sake of simplicity, a reference to “Host” (or “Host
software”) implies HDLC driver software running on a host (e.g. provided by the user) or
on the DSP (e.g. firmware).
HDLC Applications
The integrated HDLC controller opens the way for numerous applications that may be
realized with the PSB 7238 in a very cost-effective manner. Some of the more obvious
are:
Figure 26
For non-HDLC serial protocols, the transparent mode of the HDLC controllers can be
used.
Functions of the HDLC Controllers
The HDLC controllers perform the following functions:
In HDLC Mode
Bit level functions:
– flag generation/detection
– zero bit insertion/deletion after 5 ones
– CRC generation/check
– abort generation
– inter-frame time fill generation.
Programmable features for HDLC transmission:
– Idle (‘1’) or flag (‘0111111’) as inter-frame time fill
– CRC generated yes/no (if no, the frame is closed with a closing flag only).
Semiconductor Group
a) D-channel handling in point-to-point configurations, e.g. on Digital Circuit
b) Packetized voice e.g. with G.728.
Multiplication Equipment.
61
Data Sheet 1998-07-01
Functional Blocks
PSB 7238