Datasheet

ManualsBrandsMICROCHIP TECHNOLOGY ManualsMicrocontrollers, Microprocessors & QuartzesEmbedded microcontroller SOIC 14 8-Bit 20 MHz I/O number 11

PIC12F510/16F506

9.1.6 ANALOG CONVERSION RESULT

The ADRES register contains the results of the last

conversion. These results are present during the sam-

pling period of the next analog conversion process.

After the sampling period is over, ADRES is cleared

(= 0). A ‘leading one’ is then right shifted into the

ADRES to serve as an internal conversion complete

bit. As each bit weight, starting with the MSB, is con-

verted, the leading one is shifted right and the con-

verted bit is stuffed into ADRES. After a total of 9 right

shifts of the ‘leading one’ have taken place, the conver-

sion is complete; the ‘leading one’ has been shifted out

and the GO/DONE

bit is cleared.

If the GO/DONE

bit is cleared in software during a con-

version, the conversion stops. The data in ADRES is

the partial conversion result. This data is valid for the bit

weights that have been converted. The position of the

‘leading one’ determines the number of bits that have

been converted. The bits that were not converted

before the GO/DONE

was cleared are unrecoverable.

R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-0 R/W-0

ANS1 ANS0 ADCS1 ADCS0 CHS1 CHS0 GO/DONE ADON

bit 7 bit 0

Legend:

R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’

-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown

bit 7-6 ANS<1:0>: ADC Analog Input Pin Select bits

(1), (2)

00 = No pins configured for analog input

01 = AN2 configured as an analog input

10 = AN2 and AN0 configured as analog inputs

11 = AN2, AN1 and AN0 configured as analog inputs

bit 5-4 ADCS<1:0>: ADC Conversion Clock Select bits

00 = FOSC/16

01 = F

OSC/8

10 = F

OSC/4

11 = INTOSC/4

bit 3-2 CHS<1:0>: ADC Channel Select bits

00 = Channel AN0

01 = Channel AN1

10 = Channel AN2

11 = 0.6V absolute voltage reference

bit 1 GO/DONE

: ADC Conversion Status bit

(4)

1 = ADC conversion in progress. Setting this bit starts an ADC conversion cycle. This bit is

automatically cleared by hardware when the ADC is done converting.

0 = ADC conversion completed/not in progress. Manually clearing this bit while a conversion is in

process terminates the current conversion.

bit 0 ADON: ADC Enable bit

1 = ADC module is operating

0 = ADC module is shut-off and consumes no power

Note 1: When the ANS bits are set, the channels selected will automatically be forced into Analog mode, regard-

less of the pin function previously defined. The only exception to this is the comparator, where the analog

input to the comparator and the ADC will be active at the same time. It is the users responsibility to ensure

that the ADC loading on the comparator input does not affect their application.

2: The ANS<1:0> bits are active regardless of the condition of ADON.

3: CHS<1:0> bits default to 11 after any Reset.

4: If the ADON bit is clear, the GO/DONE bit cannot be set.