OS 9 Startup Disk Selector

When one does this a blue screen appears with a circular arrow icon button on the left and a right-pointing arrow icon button on the right. The candidate startup disk icons appear as buttons as the Mac polls the IDE and SCSI buses. The appearance of the disk buttons takes a while and the pointer becomes a watch with spinning hands during polling and mounting and switches back to a pointer when done. Clicking on the left circular button causes the Mac to poll again which is useful if inserting a bootable CD or turning on a startup disk at this point.

The currently selected startup disk button comes up depressed. By clicking on the other buttons, another disk can be selected to startup from. After selecting a new disk, clicking on the right-pointing arrow button continues the startup process.

This feature still needs some work. The issues are polling speed and the disk icons are indistinguishable unless they contain different operating systems. The disk icon shows the OS on the bootable disk. If you have Mac OS, Linux and/or Mac OS X, then there is no problem but if you have two or more disks with the Mac OS you can't tell which is which except for the current startup disk button which is depressed. Walt Petlevich also reported that the Startup Disk Selector continues to poll with his external SCSI chain attached to his Adaptec 2930U SCSI card which has ZIPs and Jaz drives.