Nokia Customer Care
Troubleshooting Instructions
Company confidential
NPL-4/5/
Issue 2 05/05
Copyright
© 2005
Nokia Corporation. All rights reserved.
Page 81
Figure 35: MBUS
2
1
a
1
V
headInt
V
FLASH1
V
head_min
3
a
V
low
3
Mono Headset is
recognized.
4
4
a
20ms
1. Accessory is connected (insertion & removal resistor connect to ACI line)
1a) phone gets HeadInt interrupt after 20ms check that ACI line is still low (<Vhead min)
2. Connect MBUS with HeadInt line (MBUS switch)
3. The 20 ms timer elapsed and no transition has been on HeadInt line
3a) Disconnect MBUS from HeadInt line
4. Accessory is removed. Phone gets HeadInt interrupt from ACI line low to high transition.
4a) If no HeadInt interrupt comes in the next 100ms the accessory is really removed.