Electronic Circuits and Projects Forum

0x3D14 IS only 14 bits!! 11 - 1101 - 0001 - 0100. the ' D' really should be 1 as bits 12,11 and 10 are unused..

I want to clear this why there is double __ underscore???
__config 0x3D14

so, we are using this Oscillator:-
100 = INTOSC oscillator: I/O function on RA4/OSC2/CLKOUT pin, I/O function on RA5/OSC1/CLKIN

and

MCLRE: RA3/MCLR pin function select(5)
1 = RA3/MCLR pin function is MCLR

what does this mean?

bit 13-12 BG1:BG0: Bandgap Calibration bits for BOD and POR voltage(1)
00 = Lowest bandgap voltage
11 = Highest bandgap voltage

New code for you ritesh..... Put this into oshonsoft assembler it works ok now

Code :

	;include "P16F676.inc"		;include the defaults for the chip
	__config 0x3114			;sets the configuration settings (oscillator type etc.)
							; HERE SET TO INTERNAL OSCILLATOR 4MHZ
	ORG 0
	GOTO INIT
 
INIT
	CLRF OPTION_REG
	BSF STATUS,RP0
	CLRF VRCON
	MOVLW 0x3f
	MOVWF TRISA 	; porta as input
	MOVLW 0x0
	CLRF ANSEL 	; disable ADC
	MOVWF TRISC 	; portb as output
	BCF STATUS,RP0
	MOVLW 0x7
	MOVWF CMCON
 
START
 
	btfss PORTA,1 	; test bit 1
	call delay
 
	GOTO START
 
delay
	movlw 0xff
	movwf PORTC 
	movlw 0fh
	movwf 0x21
	dECfsz 0x21,f
	clrf PORTC
	RETURN
 
end

Band gao voltage associated with BOD & POR Brown Out Detect and Power On Reset Read section 9.3.5 on this topic.

Thanks the code are working ...

ORG 0
GOTO INIT

What the need of this can't we start normally?
please explain more this part of code...

CLRF OPTION_REG??
CLRF VRCON??

Originally Posted by RITESH KAKKAR

please explain more this part of code...

CLRF OPTION_REG??
CLRF VRCON??

I was just trying to find out why the ADC wasn't being turned off.

VRCON is for the voltage reference module (it's unused, so I disabled it)
OPTION_REG has interrupt settings so I disabled them all.

ORG 0
GOTO INIT

Try to get into the habit of including this. When you use tables and interrupts you'll need to jump over them.

Sticky.
PIC16F676 Datasheet Typo.

Please clear one more doubt __config why two underscore not single is that also set in data sheet??

__config is a makro.. written by someone in microchip... To know why there is two underscores you'll need to find him and ask him.

Usually the underscore is used in C for assembler routines... purely for keeping identifiers apart.... If it was declared just config... It would mean no-one could use this identifier.

The datasheet may well have two, its depends on the font used.

Sorry... Its a directive for the assembler / linker, not a makro.....