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Engine module
Test Interfaces
The test pattern is placed on engine PWB, for service and production purposes, same test
pattern is used for after sales purposes as well.
Through MBUS or FBUS connections, the phone HW can be tested by PC software (Phoe-
nix) and production equipment (FLALI/FINUI/LABEL).
The test points are listed in the schematic diagrams
Connections to Baseband
The flash programming box, FPS8, is connected to the baseband using a galvanic connec-
tor or test pads for galvanic connection.
The flash programming interface connects the flash prommer to the UPP via the UEM
and the connections correspond to a logic level of 2.7 V. The flash prommer is connected
to the UEM via the MBUS (bi-directional line), FBUS_TX, and FBUS_RX. The programming
interface connections between the UEM and the UPP constitute the MBUS_TX,
MBUS_RX, FBUS_TX, and FBUS_RX lines. The interface also uses the BSI
(Battery_Size_Indicator).
FBUS Interface
FBUS is an asynchronous data bus having separate TX and RX signals. Default bit rate of
the bus is 115.2 kbit/s. FBUS is mainly used for controlling phone when flashing.
MBUS Interface
MBUS interface is used for controlling the phone in service. It is bi-directional serial bus
between the phone and PC. The default transmission speed is 9.6 kbit/s.
Page 26
Company confidential
Nokia Corporation.
CCS Technical Documentation
Issue 1 10/03