Can anyone explain to me what the following ADCON settings represent? I understand bits and pieces but the harder I try to wrap my head around the whole picture, the more confused I get:

ADCON0 = 0x00000101;
ADCON1 = 0b00001011;
ADCON2 = 0b10000001;

A bit by bit explanation would be ideal however any assistance would be extremely helpful as my textbook does not clearly define these registers (ADCON2 is not even in the book).

 

They are clearly explained in the datasheet, which you can get from the Microchip website.

 

ADCON0 does 3 things: turns the A2D hardware on, flags when a conversion is complete, and picks which channel is going to be converted.

ADCON1 picks the reference voltage sources (both low and high) for the end points, and picks which group of pins will be used for analog

ADCON2 picks if the result is left justified (useful for just using the upper 8 bits of the result) or right justified (useful when using the entire 10 bits), how long a delay between saying GO and the start of an acquisition, and the clock source for the A2D hardware.

Here's where the control bits appear in the code:

ADCON0 = 0x00000101;
//         --0001--    select AN1
//         ------01     GO/DONE (it's done)   
//         -------1     hardware main screen on

ADCON1 = 0b00001011;
//         --0-----     use Vss as a ref
//         ---0----     use Vdd as a ref
//         ----1011     AN0-AN4 enabled


ADCON2 = 0b10000001;
//         1-------     right justified result
//         --000---     0 TAD delay or no delay before reading
//         -----001     A2C clock is Fosc/8

BTW, that's typically how I document my code in my code so you can see how and why each bit is set, except I'll typically also tag the page number of where the register description is.

Additionally, the PIC18F4550 was an awesome device a decade ago when it was first introduced. There are much better parts available today for the same price.

 

VERY helpful. Thank you, sir.

 

ADCON0 does 3 things: turns the A2D hardware on, flags when a conversion is complete, and picks which channel is going to be converted.

ADCON1 picks the reference voltage sources (both low and high) for the end points, and picks which group of pins will be used for analog

ADCON2 picks if the result is left justified (useful for just using the upper 8 bits of the result) or right justified (useful when using the entire 10 bits), how long a delay between saying GO and the start of an acquisition, and the clock source for the A2D hardware.

Here's where the control bits appear in the code:

ADCON0 = 0x00000101;
//         --0001--    select AN1
//         ------01     GO/DONE (it's done)  
//         -------1     hardware main screen on

ADCON1 = 0b00001011;
//         --0-----     use Vss as a ref
//         ---0----     use Vdd as a ref
//         ----1011     AN0-AN4 enabled


ADCON2 = 0b10000001;
//         1-------     right justified result
//         --000---     0 TAD delay or no delay before reading
//         -----001     A2C clock is Fosc/8

BTW, that's typically how I document my code in my code so you can see how and why each bit is set, except I'll typically also tag the page number of where the register description is.

Additionally, the PIC18F4550 was an awesome device a decade ago when it was first introduced. There are much better parts available today for the same price.

which better parts would you recommend?

 

Which better parts would you recommend?

 

Hi,
This thread is from 2011. It is old. The TS has moved on. Please start your own thread, where you explain what you want to do, or what you have problems with.

Oh, and welcome to AAC. Hope you like it here.

 

Which better parts would you recommend?

P18F23k22 P18f46K22?
Max.

 

They are clearly explained in the datasheet, which you can get from the Microchip website.

Hello friend,

I think when help is needed, one should offer it. reading the data sheet is not as easy as those who have the ability to do so want it to sound.

 

Hello friend.

 

Hello friend,

I think when help is needed, one should offer it. reading the data sheet is not as easy as those who have the ability to do so want it to sound.

Come on; what he asked is explicitly mentioned, bit by bit, in the datasheet.

Most of the time you do not need to come here to ask that kind of questions.