Memory Block; Security - Nokia NSB-9 Service Manual

NSB-9
System Module and User Interface
TEA5767
VAFR
VAFL
UEM
MIC3
XEAR

Memory Block

For the MCU UPP includes ROM, 2 kbytes, that is used mainly for boot code of MCU. To
speed up the MCU operation small 64 byte cache is also integrated as a part of the MCU
memory interface. For program memory 8Mbit (512k x 16bit) PDRAM is integrated into
UPP, and 8Mbit external SRAM is in separate COMBO MEMORY chip. RAM block can also
be used as data memory and it is byte addressable. RAM is mainly for MCU purposes but
also DSP has also access to it if needed.
MCU code is stored into external flash memory, which is in a combo memory chip. The
size of the flash is 128Mbit (8M x 16bit). The NSB-9 baseband supports a burst mode
flash with multiplexed address/data bus. Access to the flash memory is performed as 16-
bit access. The flash has Read While Write capabilities which makes the emulation of
EEPROM within the flash easy.

Security

The phone flash program and IMEI code are software protected using an external secu-
rity device that is connected between the phone and a PC.
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Figure 15: IHF connections
Stereo
Amplifier
Rin
Lin
SPKRout -
Phone_in
IHF SPKRout +
Nokia Corporation
CCS Technical Documentation
IHF
Issue 1 04/03