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Thank you for your patience.

Says: " Why not split the "PICList" into multiple mailing lists (i.e.,,, etc...)? " James Newton replies: Mostly because we don't own the mailing list server (MIT is kind enough to host the list and pay for the bandwidth) and so can not ask for more than one list. The topic tag system allows you to filter out the types of messages you don't want.

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christopher dahn Says:

please can anyone supply a total newbie with any asm source code for using a ds1307 with my 16f877. i've spent 3 days searching the net for some complete code without any luck i've found some projects but have no idea what part of their code is specific to the ds1307. i'm sure there must be someone out there who uses and understands how to opperate the ds1307

please email me at

Robin C Fawell of Rhotech Says:

Sajid Naqvi of Waders Power Control Says:

I am making a 300VAC voltmeter on PIC. I need circuit diagram for linear conversion from 0-300VAC to 0-5.00VDC FSD. Both the supplies are to be isolated. Optocoupler based circuit would be great.

Derick Q Siu of EbCon Systems Ltd. Says:

Hi there,

I'm having a problem with the PIC18F452 Microcontroller specifically with the PORTA module.

I have gone through this site for tips in dealing with PIC ports, and have followed the advice of eliminating all floating pins, setting unused pins to inputs, and grounding them with a 10K pull-down resistor. Currently I am just trying to simply test my port pins so I can interface it with my LCD display.

What I have is timer1 interrupting every 500MS and turning on and of RA0,RA1,RA2, and RE0. for the most part RA2, and RE0 work fine, I am getting a pulse from them, but as for RA0 and RA1, they constantly are at 0V, and I am not sure why that is. here is a snippet of my init code and isr function:
void port_init(void)
// set PortA to output
TRISA = 0xF8;
TRISA = 0;
ADON = 0; // turn off A/D converter
//PORTA = 0x00; // clear PORT A

// set PORTB to input
TRISB = 0xFF; // set portb as inputs
PORTB = 0x00; // clear Port B
RBIP = 1; // set port b interrupt priority high
INTEDG1 = 1;
INTEDG2 = 1;
INT1IP = 1;
INT2IP = 1;
INT0IE = 1;
RBIE = 1; // enable the external interrupts

// set PORTD to output
TRISD = 0x00;
PORTD = 0x00; // clear Port D

PORTC = 0x00;
TRISC = 0xBF; // set RC6 as output

// set PORTE to output
PORTE = 0;
// part of isr routine
TMR1L = 0; // reset the timer
TMR1H = 0;
if(buff != 0xFF){
count ++;
if(count == 5)
/*--------------------Test routine------*/
if(stat == 0xFF)
RA0 = 1;
RA1 = 1;
RA2 = 1;
count = 0;
TMR1IF = 0; // reset the timer interrupt
} // end if TMR1IF

I'm not sure if it is my circuit, or in my programming, since I've been hearing that microchip is tyring to phase out the TRIS function, yet it is included in the include files and datasheets.
if anyone can helpme in this matter, it would be greatly appreciated.

Thank you,



my project is implementation of space vector modulation to multilevel inverter.
i am using pic16f877a. i need help on how to implement it in hardware and how to proceed...

See also: