How can I understand the compatibility of a bootloader?

[theasus]

How can I understand the compatibility of bootloader for any PICs?To determine the compatibility of bootloader for PIC,where should I look from datasheet?

[asmallri]

The PIC must support self programming of flash memory. If you want an incremental bootloader (one that can modify as little as a single byte of flash memory) then you need a PIC with RAM size > the PICs page erase size.
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Home of Ethernet, SD card and Encrypted Serial Bootloaders for PICs!!

[theasus]

For example I know that bootloader can't be load to 16f628. But I couldn't find anything about "self programming of flash memory" in 16f628's datasheet. How can I understand this specification?

[ckielstra]

If you want to know which processors support 'self programming' have a look at http://www.microchip.com/ParamChartSearch/chart.aspx?branchID=1002&mid=10&lang=en&pageId=74,
It is in the column named 'self-write'.

Another method is to check the datasheet. If it is not mentioned to support Self Programming then it doesn't. Microchip doesn't say 'this chip has no self programming', which is strange but I do understand from a marketing perspective. It would be a very long list to mention all the things the chip can not do (it does not fly to the moon, does not cook food, etc).
So check if there is a chapter on writing to Flash Program Memory, if this chapter is missing then the chip does not support this feature. So yes, for the PIC16F628 there is no information of self programming because the chip doesn't support it.

If you want to read more about Self Programming find a chip that does support the feature and read the datasheet.
There is also a separate manual on Flash Programming for most chips, for example for the PIC16F88: PIC16F87/88 FLASH Memory Programming Specification

[theasus]

OK thanks for your answers. I understand compatibility of bootloader for PICs thanks to you.