how can I get binary output '0'or '1' according to sign of the input value ?

Hi. I have output of ADC which give sampled value either negative or positive. I want to decode these values in binary form '1' or '0'. let say if positive value appear, the logic should show '1' otherwise '0'. it means it should be sign-based detection. this logic I need at the end of the system (difference block in attached file). is there any block in simulink or can I make customized code in MATLAB function block ? It would be appreciated if someone can help in this regard.

Thanks in Advance

[KSSV]

Have a look on sign

[Sarfaraz Ahmed]

The sign function gives -1 and 1. for example: V = [-0.5 3]; sign(V) Ans -1 1

But I want to get 0 and 1 because I have to forward these binary to XOR logic gate. so how can I decode signed values into binary ?

Thanks

Answer 1

[Ghetto blaster]

Actually what you would want is step function. heaviside() is most optimal except I assume that you want for the input value of 0 for output to also be 0? In that case you would need to set the HeavisideAtOrigin to be 0. Also I assume you want output to be logical or floating point? heaviside outputs floating.

oldparam = sympref('HeavisideAtOrigin',0);
output_logical = heaviside(input_voltage);

[Sarfaraz Ahmed]

Thanks Josip. Actually, I do not have input value 0. the model have only negative or positive values which I need to convert in 1 and 0 according to sign of the input value. Secondly, I want output to be logical not floating because in next these logical output have to be input of XOR logical gate.

[Ghetto blaster]

Okay, just add logical infront of heaviside, like this:

output_logical = logical(heaviside(input_voltage));

that oughta do it

[Sarfaraz Ahmed]

Thank you so much. It's working. I will embed these code lines in MATLAB function block and integrate with my ADC design. I accepted your answer.

So nice of you!

[Ghetto blaster]

No worries Ahmed. Glad I could help you.

[Sarfaraz Ahmed]

Hi. I embed this code in MATLAB function block but it shows an error that: Size mismatch for MATLAB expression 'heaviside'. Expected = 1x1 Actual = 1x0 and if I put output_logical = logical(heaviside(input_voltage)); then it shows an error Class mismatch for variable 'logical'. Expected 'double', Actual 'logical'.

it must be some dimension error how can I resolve this error ? snap is attached.

Thanks