DSP application

[justin_t]

Hi

This past while ive been working on a PCB with an atmel microcontroller for controlling a motor and heater for an application.

I am now at a stage where i wish to monitor the process while it is running and produce a data logging facility.

Ive considered using an SD card with some type of driver on the board that will store the events as the happen on the application, this may well be the best option.

Last night i was thinking about the possibility of using DSP as the interface between the application and the data logger.
My idea is that each application in the system will produce its own unique frequency when operating. Im considering producing a device that sits on/in the application and looks for these frequencies, when one occurs the times are logged in a dedicated chip. This means that the data logger will be seperate and retro fittable (if thats a word) to any of the applications.

The main frequencies to look for are as follows:
small motor
small heater
opening and closing of magnetic switch
buzzer

Ive done some dsp stuff with Matlab in uni but now need to apply that to a real time application.

Does anyone have any experience in this type of application?, what would i use to monitor the frequencies of the application (ive heard of an accelerometer i think for condition monitoring).

Any help appreciated

Justin_t

 

[3v0]

You could do this but there are much easier ways to log data.

The most reasonable thing is to add memory to the existing system and write to it each time you turn a device on or off.

 

[justin_t]

How difficult would it be to change the information from a micro controller to extra memory to something that would beeasily interfaced with computer software. It needs to be easily read, thats why i was thinking of using an SD card as extra memory. I rather use that method that the frequency spectrum option.

 

[3v0]

How difficult would it be to change the information from a micro controller to extra memory to something that would beeasily interfaced with computer software. It needs to be easily read, thats why i was thinking of using an SD card as extra memory. I rather use that method that the frequency spectrum option.

There is an active thread on this board where people are interfacing PICs to SD cards. Not trivial but people do it on a regular basis. If you want to interface a AVR to SD check the AVRFreeks forum.

There are two options. You can modify the existing code to do the logging as I suggested or you can add a 2nd microcontroller with sensors and have it log the data. The first is less complex.

Either way you need to know how to program. You first post seemed to indicate that you have written the code for the AVR board so adding the code to log the data should not be overly difficult. As I said adding a SD card is more difficult. An I2C EEPROM is much easier but you need to provide the hardware/software to read it on a PC.

EDIT: There is a 3rd option which is a mix of the first two. Have the AVR send info to a 2nd microcontroller which logs the data.

I do not see where using frequencies will help.