Dual Boot Based on Hardware Setting

[Lorenz, Gregory]

I have recently worked with a team to design a custom I/O card.  We are using the GRUB boot-loader to load the VxWorks OS.  However, we have the need to be able to boot to DOS as well.  I currently have this working with the menu interface, but, since this is an embedded system, we are looking to make it so that we can boot to one of the two partitions based on the value set in an IO port location.  We have a CPLD on the custom I/O card that picks up the state of a physical switch and writes a corresponding 1 or 0 to a specified I/O port.  I want to take the GRUB boot-loader, read this I/O port location, and subsequently boot to the appropriate OS.  I have been looking through the source and believe I can do it.  I was just curious if anyone had done this before, or if there is a syntax for this type of thing already defined that can be put in the menu.lst file.  Any feedback would be appreciated.

 

Thanks,

Greg Lorenz

Systems & Electronics, Inc.

Software Engineer

314.553.4133

address@hidden