WRLONG x,ptra[y] + SETQ

ManAtWork

Why does this work

		add 	ptra,#(18)*4
		setq	#writeEnd-writeStart-1
		wrlong	writeStart,ptra
		sub 	ptra,#(18)*4

but this doesn't ?

		setq	#writeEnd-writeStart-1
		wrlong	writeStart,ptra[18]

Are the uses of indexed pointer access and block transfer mutually exclusive?

ersmith

ManAtWork wrote: »

Are the uses of indexed pointer access and block transfer mutually exclusive?

Yes. The hardware only allows block transfer with a subset of pointer modes (basically just plain pointer and pointer post-increment, I think, although you should check the docs to be sure).

evanh

Huh, Eric is right. I was going to say that the plain PTRx by itself was the only sensible option but reading the docs I see there is five valid PTRx uses - https://docs.google.com/document/d/1gn6oaT5Ib7CytvlZHacmrSbVBJsD9t_-kmvjd7nUR6o/edit#heading=h.hht2hg8s4wef

Chip has thrown in some bonus combinations I hadn't even pondered.