At89c2051

R

rakeshbedi

New Member

• Jun 11, 2012

• #1

if i use the pin 12 for my analog input, where will i receive my digital output in AT89C2051.

 

Ian Rogers

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• Jun 11, 2012

• #2

This chip ONLY has a comparator... no ADC.

 

R

rakeshbedi

New Member

• Jun 11, 2012

• #3

then after comparing the analog input, what will be the output.

 

R

rakeshbedi

New Member

• Jun 11, 2012

• #4

can you please explain to me briefly the working of this comparator...

 

Ian Rogers

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• Jun 12, 2012

• #5

A comparator measures one voltage against another... The result is either true or false.

CMCON register...
____________________________________________________
| C2OUT | C1OUT | C2INV | C1INV | CIS | CM2 | CM1 | CM0 |

C2OUT and C1OUT are the conditions
You can invert the out puts as well.

 

Last edited: Jun 12, 2012

R

rakeshbedi

New Member

• Jun 12, 2012

• #6

thank u.

 

Ian Rogers

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• Jun 13, 2012

• #7

Sorry............ I have given you the answer for a PIC..... I MUST be going mad

The output of the comparator on the at89c2051 is hard wired to P3.6 (as there is no physical pin, the pin IS readable from within )

So P1.0 and P1.1 are the inputs and you read P3.6 for your answer....

 

R

rakeshbedi

New Member

• Jun 13, 2012

• #8

then the output wiil be serial digital output, right???

 

Ian Rogers

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• Jun 14, 2012

• #9

rakeshbedi said:

then the output wiil be serial digital output, right???

Click to expand...

Its a single bit... P3.6... its either high or low depending on the outcome of the comparator.....

Are you looking to read a voltage on the AN1 pin? Because as I said in post #2, this device wont read analogue signals... It has no ADC.

 

R

rakeshbedi

New Member

• Jun 14, 2012

• #10

ok now i get it, it will just compare with the reference voltage and give the result in P3.6 either 0 or 1.thank u, now i have got a clear picture.