PSB7238 SIEMENS [Siemens Semiconductor Group], PSB7238 Datasheet - Page 42

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

Semiconductor Group
3.3.3
The DSP/host communication area contains the registers to support hardware and
software interrupts and special purpose registers that support communication between
the embedded DSP and the host. In demultiplexed mode, data are available on pins on
pins AD(0-7), whereas the address is supplied on pins A(0-3). This mode gives an
additional and more microprocessor-like way of accessing the DSP/Host Com Area. The
most important registers are accessible via 3 address pins only and by the use of an
additional pin (A3) it is possible to access the complete range of the DSP/Host Com
Area. The address mapping versus the multiplexed host interface is given in Table 12.
Table 12
Address
A0-3
Host Write
DSP/Host Com Area with a Demultiplexed Host interface
Address Mapping of Multiplexed/Demultiplexed Host Interface
Demultiplexed Mode
Data D0-7
Host Read
42
Address
AD0-7
FF
FD
77
76
75
74
73
71
70
6C
6A
H
H
H
H
H
H
H
Interfaces and Memory Organization
H
H
H
H
- FE
- FC
H
H
Host Write
reserved
reserved
Acknowledge
INT MSB
Acknowledge
INT LSB
Interrupt INT
Mask MSB
Interrupt INT
Mask LSB
Acknowledge
INTR
Interrupt
INTR Mask
MSB
Interrupt
INTR Mask
LSB
reserved
reserved
Multiplexed Mode
Data AD0-7
Data Sheet 1998-07-01
Host Read
reserved
reserved
Interrupt INT
Status MSB
Interrupt INT
Status LSB
Interrupt
INTR Status
MSB
Interrupt
INTR Status
LSB
reserved
reserved
PSB 7238