receive multiple data with a single ADC

[abhishekdixit]

hello frnds,
i am using 8051 micro controller in our prograimg in which i am getting data for various multiplexer andthen these data has to tansferred to a single ADC, so here i am getting a problem that how will i give data tio the ADC0808 so that these data transferred to the ADC one by one with a particular interval of time..
Please help me.


thanx
with regards,
ABHISHEK DIXIT

 

[babatundeawe]

if u having more than one anologue samples to take. use one of the multichannel adc. i am sure they have a channel select input. this usually come in the form off address. which will allow you to select the channel you want to sample. i dont use 8051 but if u can try the pic i can provide u with a schematic and some code to start with.

cheers

 

[abhishekdixit]

hi babatundeawe,
i also work on PIC micro controller. but perhaps you that their is a much more flexibility with PIC micro controller as compared to 8051 micro controller. so it is easier to make this program inPIC, but i wanna to use this logic in 8051.

 

[babatundeawe]

ok good luck with that but if u need help as per the pic i will be glad to offer to the best of my knowledge.

cheers

 

[karthikkrv85]

hello frnds,
i am using 8051 micro controller in our prograimg in which i am getting data for various multiplexer andthen these data has to tansferred to a single ADC, so here i am getting a problem that how will i give data tio the ADC0808 so that these data transferred to the ADC one by one with a particular interval of time..
Please help me.


thanx
with regards,
ABHISHEK DIXIT

Hai

Do you mean that you will be getting digital data for multiplexer? That multiplexers output goes to ADC?

Did you really meant ADC or DAC? Because i dont think you can send a digital data to ADC.

Can you please be clear your requirement?

All the best

Thanks

 

[akvii]

analog multiplexer

 

[abhishekdixit]

Hi karthikkrv85 ,
actually i m getting various analogue signal from different temperature sensors. now i want to convert these signal into digital form so that i can gibe these values to the 8051 micro controller. but giving these value one by one i am using multiplexer. now i am getting problem to initialize ADC. which will convert my analogue data into digital.

 

[karthikkrv85]

Hi karthikkrv85 ,
actually i m getting various analogue signal from different temperature sensors. now i want to convert these signal into digital form so that i can gibe these values to the 8051 micro controller. but giving these value one by one i am using multiplexer. now i am getting problem to initialize ADC. which will convert my analogue data into digital.

Thank for your explanation. So what problem you are getting with the initialization?

As per the explanation, your multiplexer gives different channels output at a particular period. Do you know how to control this channel selection of multiplexer?

If yes, select a channel of multiplex and start conversion of ADC for the particular channel and read the digital values at the port to which the data's are connected.

Can you brief the problem what you are facing?

Thanks

---------- Post added at 08:38 ---------- Previous post was at 08:37 ----------

If possible, upload the schematic or the datasheet of multiplexer

 

[Arch Zone]

ADC0808 has analog multiplexer, so you don't have to add more multiplexer.
For example :
Channel is selected by 3 pin, p1.0, p1.1, p1.2
ADC Address Latch at P1.3
Start Conversion at P1.4
EOC at P1.5
ADC Data Line at P2
Output Enable always High

Try this :

sbit A1 at P1_0_bit;
sbit A2 at P1_1_bit;
sbit A3 at P1_2_bit;
sbit ALE at P1_3_bit;
sbit SC at P1_4_bit;
sbit EOC at P1_5_bit;

//when reading channel 0 :
A1=0;
A2=0;
A3=0;

ALE=1; //Activate and Hold New Address 
ALE=0; 

SC=1; //Start new conversiom
SC=0; 

while (EOC==1);//Read EOC 
while (EOC==0);

ADC_Data=P2;//Get it

and when reading channel 5 :

A1=1;
A2=0;
A3=1;

ALE=1; //Activate and Hold New Address 
ALE=0; 

SC=1; //Start new conversiom
SC=0; 

while (EOC==1);
while (EOC==0);
ADC_Data=P2;