System Logic Main Features; Memories - Nokia NSW-5 Series Service Manual

NSW-5
System Module UT5U
controls the transmit timing and at specified intervals sends the I/Q sam-
ples at 97.2 kHz to COBBA for TXI/Q D/A converters.
– Digital receive
In digital receive mode the second IF is 450 kHz, which is sampled at
194,4 kHz in COBBA, aliased to 61,2 kHz and then downconverted and
demodulated in DSP. The timing is controlled by System Logic. DSP per-
forms bit detection with equalizer and then convolutional decoding and
CRC checking. After this the (speech) bits are passed for speech decod-
ing (EFR). The decoded bits are converted to analog signal in COBBA,
then routed and fed to the earpiece.
– Analog modem functions
On the analog voice channel, DSP performs the signalling functions: SAT
receiving and transponding. Transmit function: ST and wide band data.
– Control and general functions
In all modes DSP controls the RF. Controlling is done physically through
System Logic, where all necessary timing functions are implemented, and
control I/O lines are provided for e.g. synthesizer loading, power control
etc.
In all transmit modes DSP takes care of the transmitted power control
(TXC) and frequency control (AFC). Also DTMF tone generation is made
in DSP.
All clocks and timing are generated from the RFC clock. In sleep mode
only the 32 kHz clock is used.

System Logic main features

– MCU related clocking, timing and interrupts (CTIM)
– DSP related clocking, timing and interrupts (CTID)
– DSP general IO–port
–reset and interrupts to MCU and DSP
– interface between MCU and DSP (API)
– MCU interface to System Logic (MCUif)
– MCU controlled PWMs, general IO–port and USART for MBUS (PUP)
– Receive Modem (Rxmodem)
– Interface to Keyboard, CCONT and LCD Drivers (UIF)
– Interface to MCU memories, address lines and chip select decoding
(BUSC)
– DSP interface to System Logic (DSPif)
– serial accessory interface (AccIf, DSP–UART)
– Modulation, transmit filter and serial interface to COBBA (MFI)
– Serial interface for RF synthesizer control (SCU)

Memories

FLASH
– size 2048k * 16 bit
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E Nokia Mobile Phones Ltd.
PAMS Technical Documentation
Issue 1 10/00