[syslinux] "Boot error" message

[braiamserafim at terra.com.br]

 Hi,
 I'm getting a "Boot error" message when the BIOS tries to boot a SPI
flash disk. I installed the syslinux on SPI flash disk mounted as a
block device. The flash was formatted as FAT12. The BIOS emulates the
flash as floppy.
 I also tried to install the bootloader using a DOS version of
syslinux running on FreeDOS. If I use this way so the BIOS boots
correctly.
 Why am I getting that error message?