Display Information: Contact Service - Nokia NSE-6 SERIES Service Manual

NSE–6
PAMS
Disassembly & Troubleshooting Instructions Technical Documentation

Display Information: Contact Service

This fault means that software is able to run and thus the watchdog of
CCONT (N100) can be served. Selftest functions are run when power is
switched on and software is executed from flash. If any of the selftests
fails, a "contact service" text is shown on display.
MCU self tests are devided to those executed while power up (start up
tests) and ones that can be executed with connected PC. The tests and
included items are as follows:
1. MCU ROM checksum
Calculates 16 bit checksum out of Flash code and compares it to one
found in Flash. Items being checked are:
MAD2 <––> Flash data– and address lines, CE0,CE1, WE, BYTE, Vcc,
GND, Flash internal functionality
2. MCU RAM interface
3. MCU RAM component
4. MCU EEPROM interface
5. MCU EEPROM component
6. RTC battery
7. CCONT interface
8. A/D converter
9. SW reset
A Power off
B. Security data
C. EEPROM tune checksum
D. PPM checksum
E MCU download DSP
F. DSP alive
G. COBBA serial
H COBBA parallel
I. EEPROM sec checksum
K. PPM validity
Original 08/98
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