Fig 35 Mbus - Nokia NPL-4 Series Troubleshooting Instructions

Nokia Customer Care
V
headInt
1
V
FLASH1
V
head_min
V
low
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.
Copyright © 2005 Nokia Corporation. All rights reserved.
Issue 2 05/05
Company confidential
Figure 35: MBUS
Mono Headset is
recognized.
20ms
2 3
a a
1 3
NPL-4/5/
Troubleshooting Instructions
a
4
4
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