Testing - Nokia NSB-7 Series Service Manual

NSB-7
Disassembly & Troubleshooting
Figure 23: R211, VPP, WinTesla Self Test, MCU Eeprom interface

Testing

The MCU software enters a local mode at start-up if suitable resistors are connected to
the BTEMP and BSI lines.
NOTE! Baseband doesn't wake up automatically when the battery voltage is connected.
Power must be switched on by
pressing the Power key or
inserting a waking pulse BTEMP line or
connecting a charger
In the local mode the baseband can be controlled through MBUS or FBUS connections by
a PC-locals software. Baseband internal connections are tested with self tests if possible.
Parameters cannot be set accurate enough by design because of component tolerances.
Due to use of 5% resistor values, the channels of the CCONT A/D converters need to be
aligned in the production phase. With in battery voltage tuning the MCU software reads
the A/D reading from CCONT at 4.1V and stores this reading to emulated EEPROM mem-
ory as a reference point. Another reference point is created by assuming that while the
input voltage is zero, A/D reading is also zero. Now the slope is known and A/D readings
Page 22 ãNokia Mobile Phones Ltd.
PAMS Technical Documentation
Issue 1 06/00