PSB7238 SIEMENS [Siemens Semiconductor Group], PSB7238 Datasheet - Page 167

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

the compressed audio through the host interface (ISEL(1-0) = 01).
After switching to IOM/host interface combination by programming the ISEL(1-0) bits in
the control block, an initialization phase is executed by the JADE in which the internal
firmware re-programs the configuration/control registers like in the default configuration
(see Section 5.3) to setup the IOM interface for the communication with the analog front
end (AFE). This initialization phase is < 10 ms.
The IOM interface is in TE mode (double DCL clock) and IC1/2 channels are selected
for the 16 bit linear data transfer between the JADE and the analog front end (AFE). The
DD line is output of the JADE, DU is input to the JADE.
This configuration may be changed by the host by just overwriting the corresponding
registers after the default initialization has been completed.
An interrupt handshake protocol is implemented for the data exchange on the host
interface. The basic timing for this protocol is determined by the uncompressed data rate
at the IOM interface. See Figure 49 for the interrupt handshake procedure:
6.2.3.2
The JADE can provide the uncompressed audio via the IOM interface while exchanging
Semiconductor Group
Uncompressed Data: IOM IF, Compressed Data: Host IF
167
Data Sheet 1998-07-01
Firmware Features
PSB 7238