====== STACKS ======
The 6x09 microprocessors contain two stack pointer registers S, and U.

The microprocessor itself uses the S or System stack pointer for all of its operations which require stack.

The U or User stack pointer is available for the developer to use as their own stack.

===== CMOC EXAMPLE =====

<code>
void stacks(word sstack, word ustack) {
	asm {
		TFR S,D
		STD sstack
	}
	printf("S STACK = %4x\n", sstack);
	asm {
		TFR U,D
		STD ustack
	}
	printf("U STACK = %4x\n", ustack);
}
</code>

{{:tandy_color_computer:stacks-coco2b.png?direct&400|Color Computer 2B}} {{:tandy_color_computer:stacks-coco3.png?direct&400|Color Computer 3}}

===== SEE ALSO =====
The Color Computer 3 also uses a [[Secondary Stack]] memory block for high-resolution drawing commands.

===== RTS =====
Return to [[:Tandy Color Computer:]]