Boot problem in pc/104 system

I have made a boot image(floopy disk) by customization of the build file. If
I use this boot image to boot my PC, everything is ok. but when I use it to
boot my pc/104 system, it display

…altboot…

then reboot the system and display above message again, I don’t know why?

My pc/104 is configured as below.
CPU: ALI M6117D (X86 compatiable) (can run win95)
Memory: 4mb