ICSP programming algorithm

[ratgod]

I have been searching everywhere for programming algorithms for the PIC, I would like to build a programmer for the PIC18F2550, PIC18F2580, PIC18F2520 and PIC16F877A.
does anyone have the algorithms for programming any of these PIC's? I have searched the microchip website and cannot find anything that says if for programming any of those.
I did come across this document http://ww1.microchip.com/downloads/en/DeviceDoc/39606c.pdf
which is entitles : PIC18FXX80/XX85 FLASH MCU Programming Specifications
it states: this document includes the programming specifications for the following devices : PIC18F6585, PIC18F6680, PIC18F8585 and PIC18F8680.

the only references I found on the CCS forum are this one: http://www.ccsinfo.com/forum/viewtopic.php?t=27209&highlight=programming+algorithm which seems to refer the PIC16F62x range.
and this http://www.ccsinfo.com/forum/viewtopic.php?t=26816&highlight= which refers to PIC12F629/675.

anybody and information?

[ckielstra]

- Go to the microchip website.
- Select Datasheet Finder
- Select your processor
- Half way down the page you find a section 'Programming Specifications'

I only checked for your first PIC18, but it seems like all PIC18F2xxx devices use the same algorithm.
PIC18F2XXX/4XXX Flash MCU Programming Specification

[ratgod]

Many thanks,
I just printed out the PDF you shown me and I found the PIC16F87xA one here http://ww1.microchip.com/downloads/en/DeviceDoc/39589b.pdf

I will read these through and try and implement them into a circuit.

thanks again

[mskala]

What is the purpose of making your own circuit when so many possibilities already exist, are pretty inexpensive, and basically guaranteed to work?

[ratgod]

It's just something I have been curious about for a while

I was also thinking of designing my own development board like the PICkit 1 type, which has its own programmer.

I was also thinking about making an open-source USB PIC programmer as I cannot see many about that catch my fancy, I have both the ICD2 and CCS IDC(USB) programmers but each have both good and bad points.

ICD2 is a very nice programmer, it has a Vdd supply but it has to be used with MPLAB (which I find very buggy) like some sort of ball and chain.

CCS ICD is an excellent programmer, it doesn't have to bootload every time you change chip family like the ICD2 does, but the only downside is that it doesn't have a Vdd feedthrough (you can enable 5v from the USB by putting the jumper inside but that is limited current), my way around that was to build a connector that sits between the ICSP cable from the ICD and the ICSP socket on the target and supplies 5v.

many thanks again

[Humberto]