User Guide

PAMS Technical Documentation System Module & UI
NHM-8NX
Issue 1 05/02 ãNokia Corporation Page 61
FLASH Interface
Flash programming in production is done through the test pads (X103) on the PWB.
Flash programming is explained in section Flash Programming.
Table 32: Flash interface signals
FBUS Interface
FBUS is an asynchronous data bus having separate TX and RX signals. Default bitrate of
the bus is 115.2 kbit/s. FBUS is mainly used for controlling phone in the production.
Table 33: FBUS interface signals
MBUS Interface
MBUS interface is used for controlling the phone in R&D and AS. It is bidirectional serial
bus between the phone and PC. MBUS can also be accessed via bottom (headset) con-
nector. In production the phone initialization is made using MBUS. The default transmis-
sion speed is 9.6 kbit/s.
Table 34: MBUS interface signals
Signal
Min Nom Max Note
TX_D 2.7V
0V
3.0V
RX_D 2.7V
0V
3.0V
GND 0V
SCK 2.7V
0V
3.0V
VPP 0V 12V Flash programming voltage
BSI 0V 2.7V Battery size indication. Falling edge
required for flash programming.
Signal Min Nom Max Note
FBUS_TX Voh 0.7*VFLASH1 VFLASH1
Vol 0 0.3*VFLASH1
FBUS_RX Vih 0.7*VFLASH1 VFLASH1
Vil 0 0.3*VFLASH1
Rise time Tr 12.5 ns for TX and RX signals
GND 0
Signal Min Nom Max Note
GND 0