Access BIOS Programmatically (MS-DOS Level)?

I know this is an esoteric problem, but I'm hoping someone's come across this before. I boot my PowerEdge servers and OptiPlex workstations from USB memory keys, USB external hard drives, and CD-ROMs. Is there a way to programmatically access the boot settings from DOS, such that I can change the boot order without going into the BIOS via F2 during boot? What I'm after is the ability to (for instance) boot from the CD-ROM, run an imaging utility, then configure the BIOS to boot from the hard drive; otherwise, unless I eject the CD, the system would continuously boot the CD: I need a way to break out of that loop.

Thanks for any info,

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Jim