Cbus Interface; Fbus Interface; Eci Interface; Usb Charger Interface - Nokia RM-333 Service Manual

CBUS interface

CBUS is a main system control bus in BB5. RAPIDO controls the functionality of EM ASICs AVilma (N2200) and
Betty (N2300) with CBUS.
CBUS is a four-wire half-duplex master-slave interface. In HW53 CBUS clock frequency is 4.39 MHz.

FBUS interface

FBUS is a 2-wire serial communication bus between HW53 engine and service SW.

ECI interface

The ECI (Enhancement Control Interface) is a point-to-point, bi-directional, single line serial bus.
The purpose of the ECI is to identify and authenticate the accessory, and to act as a data bus (intended for
control purposes) between the phone and the accessory .

USB charger interface

The main battery can be charged from the USB port. Default charging current level is 80 – 100 mA during the
initial charging. Primary charging current level is up to 500 mA from USB Host and up to 1.25A from USB wall
charger with external switch-mode USB Charger BQ24150.
Page 8 –14
Figure 67 HS USB block diagram
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RM-333; RM-334; RM-335
System Module and User Interface
Issue 2