Data collection?

[SBWink]

hi guys i'm currently having a project that requires me to extract data from a pedometer and store the data collected into a PDA. I've opened a cheap pedometer to try to tap the signal but i don't know how to do that. Then i decided to come up with a counter circuit on the breadboard to simulate steps via pressing a button. My problem now is i don't know how to collect the signal and put them into the PDA via USB connection. How to program the USB interface? i know nothing about that as well. I found out that LABVIEW can program the PDA but i just don't know how to get the project up and running according to my plan.

Hope you guys can give me advices and guidance to this problem of mine. Thanks!!

 

[BartSimpson]

Doh! Talk about doing things the hard way.

If you have opened the Pedometer, what IC's are inside it ?
It will probably have an accelerometer in there somewhere. You may be able to tap into it's output signal provided you don't load the line.

As for USB, forget it. It is as messy as all hell and convoluted to buggery. Most if not all PDAs actually have a simple serial interface. When you plug them into their docking stations, base units or whatever, the dock handles the serial to USB stuff. Learn how to program the serial interface for your PDA it will be a lot easier. To do this you are going to need to learn how to program your PDA using whatever toolkits the PDA manufacturer will supply. Palms seem to be well supported in this area by both Palm and Open Source groups.

From what I have seen of Labview it is a product which is really aimed at getting you to buy their interface products. Their development tools ( if you could call them that ) are quite large, clunky, and build horrible front-end programs which seem to usually end up containing hundreds of little sub-modules to do the easiest things. IMNSHO, Labview is targeted more towards the automation blokes who need to build one off controllers for process control (factory automation) and the like.

For your project, you firstly need to learn how to write simple application programs for your PDA. Then you need to look closely at your pedometer, identify the components and try to determine which device is detecting the movement. You will do this by searching for the datasheets for the components. Once you have this, you should then see if you can tap a line out of this device. Alternatively, the pedometer must be displaying its output somehow.

 

[SBWink]

Thanks for the reply..i've tried to find the datasheets for the pedometer but i couldnt find any. I have opened up the pedometer but i cant really do anything with it. To make matters worse, my PDA doesnt have a serial interface, how am i going to get the project done?!?! If i cant get anything from the pedometer, i'll have to construct a counter circuit to simulate the counting but if that's the case, how am i going to interface it to the USB on the PDA?? i'm sorry for all the questions but can anyone help give me an idea?? Thanks!!

 

[Nigel Goodwin]

Thanks for the reply..i've tried to find the datasheets for the pedometer but i couldnt find any. I have opened up the pedometer but i cant really do anything with it. To make matters worse, my PDA doesnt have a serial interface, how am i going to get the project done?!?! If i cant get anything from the pedometer, i'll have to construct a counter circuit to simulate the counting but if that's the case, how am i going to interface it to the USB on the PDA?? i'm sorry for all the questions but can anyone help give me an idea?? Thanks!!

How about using a serial to USB converter, you can buy them cheaply at any computer shop - or you can buy chips to do it, but probably not a lot cheaper!.