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TonyDuell · 12th Sep 2017, 4:46 am

Actually, isn't the 6802 a 6800 with a little bit of RAM on-chip too?

After a reset, these processors read the 2 bytes at the very top of memory, locations 0xFFFE and 0xFFFF. They stick those together to make a 16 bit number (I can't remember which is the high byte and which is the low byte, but it's in the datasheet) and then jump to that address. And start executing code there. The top 2 locations are not themselves a JMP (or any other) instruction.

12th Sep 2017, 4:46 am	#4
TonyDuell Dekatron Join Date: Jun 2015 Location: Biggin Hill, London, UK. Posts: 5,208	Re: Help with 6802 Microcontroller Actually, isn't the 6802 a 6800 with a little bit of RAM on-chip too? After a reset, these processors read the 2 bytes at the very top of memory, locations 0xFFFE and 0xFFFF. They stick those together to make a 16 bit number (I can't remember which is the high byte and which is the low byte, but it's in the datasheet) and then jump to that address. And start executing code there. The top 2 locations are not themselves a JMP (or any other) instruction.