I'm not sure what is that algorithm? I got my algorithms from
Programming Spcifications for PIC16C6X/7X/9XX OTP MCUs (30228h.pdf).

Robin Abbott wrote:
>
> Kyle
>
> I assume that you are using the EEPROM programming algorithm with the C84?
>
> Robin Abbott - robin.abbott@fored.co.uk
>
> **************************************************************************
> *
> * NEW from FED - WIZPIC - visual PIC development
> *     - see web site for more details !
> *
> * Forest Electronic Developments
> * http://www.fored.co.uk
> *
> **************************************************************************
>
> ----- Original Message -----
> From: Kyle Stemen <arkia@COLUMBUS.RR.COM>
> To: <PICLIST@MITVMA.MIT.EDU>
> Sent: 22 November 1999 23:59
> Subject: Problems with custom made programmer
>
> > I am trying to make my own programmer for the PIC16CXX series. I have
> > gotten to
> > successfully work with the PIC16C74A, but it does not work at all with
> > the PIC16C64. My
> > programmer interfaces through the parallel port. My VPP is very close to
> > 13 volts.
> >
> > What could the problem be? All of my timing is extra slow. Is there a
> > limit to how long I can
> > wait? The specifications do not mention any limit. Does VPP have to
> > first stay around 5V
> > before it goes up to 13V? What kind of voltages are needed for a logic 1
> > and 0 on the data
> > and clock lines? When the PIC is outputting data how much current can it
> > sink or source? Is it
> > ok if I keep the power on most of the time, even when VPP is not on?
> > What differences could
> > the be for programming between the PIC16C64 and the PIC16C74A? I have
> > checked both chips
> > with the official programmer and they both work