A discussion group for the PICMicro microcontroller. Also called the Microchip PIC, this list is dedicated to the use and abuse of this fine, simple, microcontroller. Close to topic posts are welcome, ie. general electronics.
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Hi, I'm using the Tait Flash PIC Programmer and "Classic" interface, I can program a 16F877 but not a 16F877A, what is the difference between both? I can read, erase but not Write the 16F877A. With the 16F877 everything works OK. I try changing the differents software delays but I can not program the 16F877A |
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There is a HUGE difference in the programming algorithm. You can get the details from Microchip but basically the 'A' version is programmed 4 words at a time versus 1 word for the original. Unless your programmer is known to be capable of doing the 'A' version, you need to reconsider either the device or the programmer. --- In , fjch100 <no_reply@y...> wrote: > Hi, I'm using the Tait Flash PIC Programmer and "Classic" interface, > I can program a 16F877 but not a 16F877A, what is the difference > between both? > > I can read, erase but not Write the 16F877A. With the 16F877 > everything works OK. I try changing the differents software delays > but I can not program the 16F877A |
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> There is a HUGE difference in the programming algorithm. You can get > the details from Microchip but basically the 'A' version is > programmed 4 words at a time versus 1 word for the original. > > Unless your programmer is known to be capable of doing the 'A' > version, you need to reconsider either the device or the programmer. Agreed with the above, and I add: The *read* algorithm for all 14-bit PICs is the same, so the fact that you can read (using a 16F877 algorithm) does not imply that you can also write (or erase). Unless your programmer and/or PC software explicitly mention the 16F87xA you should not expect to be able to use this chip. Wouter van Ooijen -- ------------------------------------------- Van Ooijen Technische Informatica: www.voti.nl consultancy, development, PICmicro products |
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--- In , "Wouter van Ooijen" <wouter@v...> wrote: > > There is a HUGE difference in the programming algorithm. You can get > > the details from Microchip but basically the 'A' version is > > programmed 4 words at a time versus 1 word for the original. > > > > Unless your programmer is known to be capable of doing the 'A' > > version, you need to reconsider either the device or the programmer. I have to disagree with the above statement. It is the programming software, not the hardware that cares about the programming algorythm. Unless you are doing low-voltage programming, which I do not believe the original poster is doing since he mentioned measuring /MCLR at 12.68 volts, the programmer doesn't care if you are writing to a 16F877 or 16F877A |