[EricMao]

Hi all
I want to develop program in cortexA8, If i choose --cpu=Cortex-A8 in compiler , assembler, linker options, and the Debugger target as Cortex-A8

Welcome to RealView Debugger v4.1.2

Recent Images:
'E:\DSP\arm_ws\yuv2rgb\Debug\yuv2rgb.axf'
Recent Connections:
ARM_Cortex-A8_0@ISSM_1 (connected)
ARM_Cortex-A8_0@ISSM

After load the image,the disassembly window shows:
PC_start:
S:00000000 00000000 ANDEQ r0,r0,r0
S:00000004 00000000 ANDEQ r0,r0,r0
S:00000008 00000000 ANDEQ r0,r0,r0
S:0000000C 00000000 ANDEQ r0,r0,r0
S:00000010 00000000 ANDEQ r0,r0,r0
S:00000014 00000000 ANDEQ r0,r0,r0
S:00000018 00000000 ANDEQ r0,r0,r0
S:0000001C 00000000 ANDEQ r0,r0,r0
S:00000020 00000000 ANDEQ r0,r0,r0
S:00000024 00000000 ANDEQ r0,r0,r0
S:00000028 00000000 ANDEQ r0,r0,r0
S:0000002C 00000000 ANDEQ r0,r0,r0
S:00000030 00000000 ANDEQ r0,r0,r0
S:00000034 00000000 ANDEQ r0,r0,r0
S:00000038 00000000 ANDEQ r0,r0,r0
S:0000003C 00000000 ANDEQ r0,r0,r0
S:00000040 00000000 ANDEQ r0,r0,r0
S:00000044 00000000 ANDEQ r0,r0,r0
S:00000048 00000000 ANDEQ r0,r0,r0
S:0000004C 00000000 ANDEQ r0,r0,r0
S:00000050 00000000 ANDEQ r0,r0,r0
S:00000054 00000000 ANDEQ r0,r0,r0
S:00000058 00000000 ANDEQ r0,r0,r0
S:0000005C 00000000 ANDEQ r0,r0,r0
S:00000060 00000000 ANDEQ r0,r0,r0

[ttfn]

Could of possibilities spring to mind....

1) The debugger by default sets the PC to the image's entry/start address. You may de-selected this option, in which case the PC would stay at the reset value.
2) The image's entry point is deliberately 0x0, and the image has 0s at address 0x0. This seems unlikely - but possible.
3) You image doesn't have an entry point, in which the default is (I belive) 0x0. This seems the most likely.

For three, the linker sets the entry point in the ELF header. The entry points are specified in source file. If multiple source files define entry points the linker won't know which one to use, so you have to specify one. Oddly, if you forget to specify it doesn;t set any.

[EricMao]

Hi ttfn
Thank you for reply!
I'v sloved the problem. If channge to cortexa8, must add a function init_cpu before main() function.