bryan@ihnet.ATT.COM (b. k. delaney) (01/16/88)
When you use AHDI to boot off of a hard disk you should have a floppy disk in drive A. The ST will not boot off of this disk unless it has a boot sector on it. With a formated disk in drive A the ST will boot Very quickly from the hard disk. I usually keep a copy of "SHIP.PRG" on drive A, which I usually run before I turn off the HD. Note be sure there are no open windows to the Hard Disk when you run SHIP.PRG. As for why the light stays on, I can only guess it has to do with the fact the ST is trying to read drive A when no disk is in drive A, and therefore is getting some sort of read/drive error. Unlike MS-DOS system The ST looks for a BOOT sector first at the Cartridge Port then on Drive A, Drive B then it looks for a Boot sector on DMA Logical Unit 1 (The Hard Disk), If it finds a boot sector on drive A it boots drive A and If It Does not Find a boot Sector on Drive A it looks else where until it finds a Boot Sector. When you Instal AHDI you are actually installing a Boot Sector on the Hard disk. ihnp4!ihnet!bryan Bryan DeLaney AT&T Bell Laboratories.
landon@apple.UUCP (Landon Dyer) (01/21/88)
In article <593@ihnet.ATT.COM>, bryan@ihnet.ATT.COM (b. k. delaney) writes: > > When you use AHDI to boot off of a hard disk you should have a floppy disk > in drive A. The ST will not boot off of this disk unless it has a boot > sector on it. With a formated disk in drive A the ST will boot Very quickly > from the hard disk. I usually keep a copy of "SHIP.PRG" on drive A, which > I usually run before I turn off the HD. Note be sure there are no open > windows to the Hard Disk when you run SHIP.PRG. As for why the light stays > on, I can only guess it has to do with the fact the ST is trying to read > drive A when no disk is in drive A, and therefore is getting some sort of > read/drive error. The vbl routine that does floppy-disk deselection checks if the DMA chip is in use. If it's busy, the vbl can't do the deselect. Also, some drives don't return INDEX pulses unless a disk is inserted. > Unlike MS-DOS system The ST looks for a BOOT sector first at the Cartridge > Port then on Drive A, Drive B then it looks for a Boot sector on DMA Logical > Unit 1 (The Hard Disk), If it finds a boot sector on drive A it boots drive A > and If It Does not Find a boot Sector on Drive A it looks else where until it > finds a Boot Sector. When you Instal AHDI you are actually installing a Boot > Sector on the Hard disk. Not quite. The startup sequences goes more like: <various ways of starting up a cartridge, too baroque to mention here> <attempt to boot from drive A> (it might load and execute code, then continue, or it could take over the system) <attempt to boot from ACSI devices 0..7> o the first one "wins", because: o non-blitter ROMs have a nasty boot bug that causes the system to lock-up when reading device 1, if device 0 exists. "Fixed" by boot-stopper code written to device 0's boot sector that halts booting on the first device with this code. <run the AUTO folder on the boot drive> <bring up the desktop> In bootable AHDI, the last two steps are actually performed by the driver loaded from the hard disk. I also forget when RAM packages are executed (just before the AUTO folder, I think) but I know that they don't happen with AHDI, but they do with the ROM. Allan? -Landon -- I speak for me.
koreth@ssyx.ucsc.edu (Steven Grimm) (01/29/88)
In article <173@actisb.UUCP> federico@actisb.UUCP (Federico Heinz) writes: >Well, maybe I'm doing something wrong, but my Mega just refuses to boot from >floppy when the hard disk has a boot sector. It doesn't care whether there's >a diskette on drive A: or whatever. DCFormat has an option to write a "hard disk override" boot sector to a floppy. Usually the floppy boot code essentially passes control over to the DMA booter. > > /////// > //____ // > Federico // // "In dubio pro libido" > // __ // >BIX: fheinz // / / // >UUCP: ...!unido!tub!actisb /////// > >DISCLAIMER: I actually don't need any, but I didn't want to dissapoint you. +New! Improved! Now 100% Artificial-+-+-----------------------------------+ |# # @@@ **** &&&&& $$$$$ % %| |Steven Grimm | |# # @ @ * * & $ % %+-+ ARPA: koreth@ssyx.ucsc.edu | |### @ @ **** &&&& $ %%%%%| | UUCP: ...!ucbvax!ucscc!ssyx!koreth| |# # @ @ * * & $ % %+-+ ______________________________| |# # @@@ * ** &&&&& $ % %| | |"Let's see what's out there."| +-----with NutraSour(TM)! No natural colors or preservatives!------------+
tainter@ihlpg.ATT.COM (Tainter) (01/30/88)
In article <173@actisb.UUCP>, federico@actisb.UUCP (Federico Heinz) writes: > Well, maybe I'm doing something wrong, but my Mega just refuses to boot from > floppy when the hard disk has a boot sector. > This was pretty painful when I put a corrupted > desk accessory on the root directory of this drive: there was no way to boot > from diskette other than leaving the hard disk off, but then I was unable > to delete the dreaded accessory that kept trashing the machine every time > I left the disk on. > Federico // // "In dubio pro libido" Federico (sic) and others you may need to know: If you boot your machine with the HDisk off and then manually run the AHDI driver you get booted up from an alternative device and still have access to the harddisk. This is how you deal with the above problem. Also, DESKTOP.INFO is written to the boot device. --j.a.tainter