not getting output from ADC!

[upasana2007]

Hi all,

As a part of a larger project, I have to read analog data through ADC 0809, send the data to 8051 microcontroller and then to PC(MATLAB) serially. Everythings fine wen I am using the evaluation board in our lab...but the ADC n this board has only 1 channel available and i need 6....so I am using a separate ADC.....but using this I am not getting any output from adc at all!
I am using a 555 timer generating 640Khz wave(specified in datasheet) for clock.
I even tried using a square wave generator instead. i dint get any results.....so i connected the clock of the on board ADC to my external ADC....still no result.....wats going wrong?

 

[chetanctiemt]

hello upasna.
can i get some sort of illustration for the above statement.so i'll be able to understand your question well and will be able to reply you better..

 

[upasana2007]

hello upasna.
can i get some sort of illustration for the above statement.so i'll be able to understand your question well and will be able to reply you better..

Hi....thanks for taking an interest,,,,my problem is that the ADC is giving zero values for all input. The programming is correct as the onboard adc is working correctly.....
you want an illustration? as in ckt diagram?