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Connecting XDA to Nokia CARKIT

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Supergrobie

Member
Jan 22, 2003
27
0
Germany, Aachen
www.sto-it.de
HI!

Andrew has connected his XDA to the Carkkit (4Handy 3330).
Now I have the Carkkit (4 5110,6110,6210,7110) and the central module
is another than the one from Andrew. Is is the HFU-2.

Mic +, Ear + and Ground is no Problem. But I don't know to find the
Mic- (the pin to enable the car Kit).
It goes not online when no Nokia is connected... If somebody knows which Port to use???

An techmanual at : http://www.gsmzone.co.uk/Manuals/Nokia/Nokia_5110_Service_Manual/hfu2a3.pdf

it must be at x100 (connector)???

Thanx 4 helping!

Stevie
 
Jan 19, 2003
32
0
Dublin
Nokia HFU-2 to XDA

Hello,

I have done some investigation about connecting the xda to the hfu-2 using the link above. Its going to be a lot more difficult that connecting it to a 3330 kit (which is analogue, see www.farrella.com).

The 6210 etc gives its phone state through the MBUS lead. This information is in DIGITAL MODE!!, so an analogue voltage signal WILL NOT DO.

I connected just GND and MBUS of the phone to the cradle and the radio mute worked. I also measured the voltage of MBUS to GND in the cradle and its always 2.8V, there was no change in this voltage when on or off 'hook'. There might be another way via the headset/data connector. I will investigate this further.

Andrew Farrell 8)
 
Jan 19, 2003
32
0
Dublin
Supergrobie this is 4 u!

Here are the pin outs of the HFU-2 Kit

15 Pin Connector (Pin 1 nearest SPK)

1 NC
2 XMIC
3 SGND
4 XEAR
5+6 LOGIC_GND
7 CHARGE_CTRL
8+9 V_IN
10 MBUS
11 LOGIC_GND
12 VB
13 FBUS_RX
14 FBUS_TX
15 NC

10 Pin connector (pin 1 is nearest power input connector)

1 NC
2 +10V
3 FBUS_RX
4 MBUS
5 H/S_HOOK
6 FBUS_TX
7 GND
8 H/S_MIC
9 H/S_EAR

I'd say that using pins 5/7/8/9 that the XDA MIGHT be able to be connected to this 10 PIN connector (usually not used as its for a data/head-set).

Pin 5 could hold the key OR by using a schmitt trigger & 555 timer to hold for say 3 secs

I found an site that calculates the resistor values for a schmitt trigger:
http://hyperphysics.phy-astr.gsu.edu/hbase/electronic/schmitt.html

and for a 555 timer:
http://www.uoguelph.ca/~antoon/gadgets/555/555.html

So a Radio mute can be achived by combining these circuits together.

Andrew