新手求教嵌入式汇编实验题

[py330316117]

要求：完成10个字节数据的升序排列
有个字节复制的例子可以参考：
#*********************************************************************************************
# NAME: ARMcode.s *
# Author: Embest *
# Desc: ARMcode examples *
# copy words from src to dst *
# History: shw.He 2005.02.22 *
#*********************************************************************************************

/*------------------------------------------------------------------------------------------*/
/* constant define */
/*------------------------------------------------------------------------------------------*/
.global _start

/*------------------------------------------------------------------------------------------*/
/* code */
/*------------------------------------------------------------------------------------------*/
.text
.equ num, 20 /* Set number of words to be copied */

_start:
ldr r0, =src /* r0 = pointer to source block */
ldr r1, =dst /* r1 = pointer to destination block */
mov r2, #num /* r2 = number of words to copy */

mov sp, #0x400 /* set up stack pointer (r13) */
blockcopy:
movs r3,r2, LSR #3 /* number of eight word multiples */
beq copywords /* less than eight words to move ? */

stmfd sp!, {r4-r11} /* save some working registers */
octcopy:
ldmia r0!, {r4-r11} /* load 8 words from the source */
stmia r1!, {r4-r11} /* and put them at the destination */
subs r3, r3, #1 /* decrement the counter */
bne octcopy /* ... copy more */

ldmfd sp!, {r4-r11} /* don't need these now - restore originals */

copywords:
ands r2, r2, #7 /* number of odd words to copy */
beq stop /* No words left to copy ? */
wordcopy:
ldr r3, [r0], #4 /* a word from the source */
str r3, [r1], #4 /* store a word to the destination */
subs r2, r2, #1 /* decrement the counter */
bne wordcopy /* ... copy more */

stop:
b stop

/*------------------------------------------------------------------------------------------*/
/* make a word pool */
/*------------------------------------------------------------------------------------------*/
.ltorg
src:
.long 1,2,3,4,5,6,7,8,1,2,3,4,5,6,7,8,1,2,3,4
dst:
.long 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0

.end


PS：因为是刚学汇编，理论学的倒是挺好，不知道实际怎么开发，看大多数人并不把重点放在写代码上，但是我想先打好基础，c语言我学的不错，但是汇编完全没思路 ，能介绍写嵌入式汇编的书吗，好的文章页行，在网上查的一些觉得不实用，只做实验部给经验的也很感谢，要是给我介绍下经验的就爱死你了

[py330316117]

还是没人答啊，人烟稀少啊

[py330316117]

我发错版块了吗？怎么没人回答

[py330316117]

我发错版块了吗？怎么没人回答