Baseband Testing; Alignments; Baseband Startup For Testing - Nokia NSB-6 Series Technical Documentation Manual

NSB–6
System Module

Baseband Testing

The MCU software enters a local mode at startup if a dummy battery is
attached and the battery temperature value is high enough. This means
that the fixed resistor on the BTEMP line must correspond to a tempera-
ture higher than +85 C. 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. By connecting
MAD2 pin ROW5 to ground, MAD2 pins are toggled as a daisy chain,
which can be used for detecting short circuits in MAD2 pins. Test pads will
be placed on engine pcb for service and production trouble shooting pur-
poses in some supply voltage and signal lines.

Alignments

Within alignment those parameters are adjusted, that cannot be set accu-
rate enough by design, because of component tolerances.
Due to use of 5% resistor values, the channels of the CCONT A/D con-
verters need to be aligned in the production phase.
Within battery voltage VBATT tuning the MCU software reads the A/D
reading from CCONT at 3.6V and stores this reading to EEPROM
memory as a reference point. Another reference point is created by as-
suming that when the input voltage is zero, A/D reading is also zero. Now
the slope is known and A/D readings can be calibrated. Calibration is in-
cluded in VBATT A/D reading task.
Battery charging voltage VCHAR and current ICHAR are calibrated using
one test setting. Test jig in production line must have a connection to bat-
tery terminals. ICHAR is adjusted to 500mA and VCHAR to 8.4V with ap-
propriate load connected to the battery terminals.
BTEMP is calibrated with 47kohm resistor.
BSI is calibrated with 22kohm resistor.

Baseband Startup for Testing

When an unprogrammed module is powered up the first time the MCU
starts from the boot rom inside the MAD2. The MBUS line is to be kept
low to inform the MCU that the flash prommer is connected and the MCU
should stop after the boot and wait for a download code.
When the flash programming is performed successfully the MCU switches
to flash prom software. If the baseband is powered up for the first time the
MCU will remain in local mode as the factory set has not been executed.
To allow re–programming of working modules the MCU is at startup
forced into local mode by connecting the BSI and BTEMP signals to
ground using specified resistors.
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PAMS Technical Documentation
Issue 1 06/2000