User Guide

Nokia Customer Care System Module
6015/6015i/6016i/6019i (RH-55), 6012 (RM-20)
Issue 1 - Revision 002 09/2004 ©2004 Nokia Corporation Company Confidential Page 23
The following diagram illustrates accessory detection/external audio flowchart:
Figure 7: Accessories detection flowchart
Accessory
detection
Headint from hi to low tran
Power Vout line
Enable Vbus if USB not in use
Connect MBUS to Headint line
= 4.7k pullup to headint line
USB
detection
High to low tran in Vp
and Vm - lines
Connect 1.3k resistor to D+ line
Host with detect phone as
full speed device
USB host
detected
ACI or Fbus
accessory connected
Start ACI detection
Low to high tran in
Headint line in 20ms
Disconnect MBUS
from headint
Disable FBUS
Unpower VOUT line
Basic
headset
detected
Send ACI reset pulse
3.th trial?
Phone gets learning
sequence from ACI
ASIC
Read acc features
from ACI ASIC
Enable FBUS HW and
set FBUS to
requested command
mode, default is AT
command mode
Wait accessory ID
from Fbus Rx line
FBUS needed?
Nokia Serial Bus
accessory detected
(AT mode)
Fbus accessory
detected (phone
mode)
ACI accessory
detected
Headint YES
NO
YESNO
YES
YES
NO
NO