I thought I'd try chase up what gave me the impression of a JMPF. I'm guessing it was the mention of a far-jump here:
Although, looking more closely, it turns out that Paul mentions you need to do "SED, SED, then JMP low_word, high_word" to make this happen.
So looks like I was mistaken, there's no JMPF, it was just my misunderstanding.
Still, typing such a far-jump via the in-built assembler would be a bit tricky too, right? So my little example would still be a little problematic.
A 80C000 INC $D020
80C003 INC $D021
80C008 JMP $C000
80C00B how to type ".word $0080" here?
Perhaps you could insert the $0080 value into the desired $80c00b address manually by entering the byte values there via the monitor, but again, that feels a little cumbersome. And also, when you try disassemble that region of code, it'll look garbled too, with the extra byte after the JMP interpreted as an opcode.
Anyway, I'm sure the in-built monitor will be fine for a bit of manual tinkering, but once you really want to sink your teeth into it, and use new techniques like the far-jump, then an a cross-compiler, such as the ones mentioned before, is probably the way to go.