Help me to figure out how to connect this device

[kenev]

Hello,
I have this cycling computer:

http://ciclosport.com/en/produkt/171/cm-4-41-a

which can be connected to a PC via this USB Interface:

http://ciclosport.com/en/produkt/194/pc-set-tool-cm

Since this interface which is sold separately as an accessory for a substantial amount of money (considering the shipping cost as well) and since I had a spare handlebar bracket like this:

http://ciclosport.com/modules/cicloSport/frontEnd/images/product_1_16_13.jpg

I thought of building the USB interface myself. The USB interface has just two contacts, which should normally be for the D+ and D- lines.

Since I am not an expert, but just a quite experienced DIYer (mainly in audio), I searched around to find any information useful for my "project". As far as I found out, one of the differential data lines needs to be pulled up through a 1.5 kohm resistor, namely, for full bandwidth devices, D+ must be pulled high and for low bandwidth devices, D- must be pulled high. Is that the scheme I must follow to connect this device? And if yes, which line must be pulled high? I am a bit reluctant to proceed with this, since I want to get first an expert's opinion and advice.

Here is the download link for the program (Windows):

http://ciclosport.com/en/download/start/125/settingsbox-windows

and here is the download link for the Windows driver:

http://ciclosport.com/en/download/start/126/pc-set-tool-driver-windows

Looking forward for any expert's advice,

Evangelos

[Jan Axelson]

From the photo, it looks like the adapter has a conventional USB series-A plug and a socket for the device. I will assume that the two contacts you mention are in the socket (and on the device).

Besides the data lines, every USB device must have a connection to the VBUS and GND lines so it can detect attachment.

So I'm wondering if the socket and/or plug have USB intelligence built into them. In other words, circuits inside the socket or plug manage the USB communications using data from the device. In that case, you would need to duplicate that functionality by programming a USB controller that connects to the device.

Maybe the two contacts just detect the device's presence and the adapter uses wireless to communicate with the device.

Without a device to look at, it's hard to say. But in any case, I think you would need much more than some wires and a resistor.

[kenev]

Dear Jan,

Thank you for your immediate reply.

So it seems it's something more complicated than I first thought and it is beyond my skills and not worthy trying it. I have no other option than buying the USB adapter.

Thank you once again,

Evangelos