Writing a mismatched biosdsi9.rom to a motherboard will almost certainly cause a no-boot situation. The firmware includes platform-specific initialization code for the CPU, memory controller, Super I/O, and embedded controllers. There is no universal BIOS file.
is a required system file for emulating the Nintendo DSi in ARM9 mode. It is a dump of the internal BIOS (Basic Input/Output System) from the DSi hardware. Functional Overview biosdsi9.rom
The Nintendo DSi utilizes a dual-CPU architecture featuring an processor and an ARM7 processor. Writing a mismatched biosdsi9
Quick checklist you can run now (copy-paste): biosdsi9.rom
Understanding biosdsi9.rom: The Core of Nintendo DSi Emulation