Motorola SC140 user manual First Code Section

Compiler Support on StarCore

The following instructions require data to be aligned on the specified boundaries:

move.w	(r0),d0	2-byte boundary
move.f	(r0),d0	2-byte boundary
move.2w	(r0), d0:d1	4-byte boundary
move.2f	(r0), d0:d1	4-byte boundary
move.4w	(r0),d0:d1:d2:d3	8-byte boundary
move.4f	(r0),d0:d1:d2:d3	8-byte boundary
move.l	(r0),d0	8-byte boundary
move.2l	(r0),d0:d1	8-byte boundary

Hands On

1.Open the Ex4.c file, which contains a series of assembly instructions within a C framework using asm statements. For alternative (and nicer) ways of incorporating assembly code, consult the SC100 C/C++ Compiler User’s Manual.

2.Look at the assembly instructions to understand the wide data move instructions. Notice that the code comprises two sections: the first section with aligned data and the second with non-aligned data.

3.For each instruction, write the result you expect from each section in the boxes provided here (in the Expected Columns). Array “data[ ]” is of type long int and therefore aligns on a 4-byte boundary.

data:	0x01	0x231 0x45 0x67 0x89 0xAB				0xCD		0xEF
	0xAA	0xBB 0xCC 0xDD 0xEE 0xFF					0x11	0x22
move #data,r0				Expected				Simulator
		r0
			00	0000	0100
move.w (r0),d0
		d0
move.2w (r0),d0:d1
		d0
		d1
move.2f (r0),d2:d3		d2
		d3
move.4w (r0),d4:d5:d6:d7		d4
		d5
		d6
		d7
move.2l (r0),d8:d9		d8
		d9

First Code Section

14 Introduction to the SC140 Tools