My work partition came up unvalidated today, and I cancelled the requester, which meant it remained in that state.
I tried to boot from the OS4.1 CD and although the kickstart was?loaded from the CD, workbench was loaded from my hard drive, and everytime I tried to use Partition Wizard top sort out the problem my system just froze.
After several attempts I decided to re-boot from my OS4.0 partition, and see if I could sort out my problem from there. When going into Media toolbox I had the following boot priorities set up:-
All I did was change the OS4.1 boot prority to 8 to boot in to my old(?) OS4.0 partition.
So my question is, is the default boot priority of the optical drives 10, and is there anywhere to change that as this restriction isn't in the documentation anywhere?
As Chris says, the CD is at priority 10, so I would suggest you lower your HD priorities accordingly, or hold down the "Scroll-lock" key after kickstart has loaded to enter the Early Boot Screen, where you can select the CD manually.
So my question is, is the default boot priority of the optical drives 10,
Yes.
Quote:
and is there anywhere to change that
No.
Quote:
as this restriction isn't in the documentation anywhere?
What restriction? On classic Amigas it's +5 for the floppy and you can use even less priorities for HD partitions ("only" 132 different ones instead of 137 on the AmigaOne). HD partitions should have boot priorities <= 0, and unless you have more than 128 bootable partitions (0, -1, ..., -127) there is no restriction at all, but even if you do have more there is no restriction: There is always only one partition which boots by default, the one with the highest boot priority, and you have to select others in the boot menu. The boot partition you use should have priority 0 and for the currently unused ones it doesn't make any difference if they have different boot priorities (-1 ... -127) or all the same one (-1).
What restriction? On classic Amigas it's +5 for the floppy and you can use even less priorities for HD partitions ("only" 132 different ones instead of 137 on the AmigaOne). HD partitions should have boot priorities <= 0, and unless you have more than 128 bootable partitions (0, -1, ..., -127) there is no restriction at all, but even if you do have more there is no restriction: There is always only one partition which boots by default, the one with the highest boot priority, and you have to select others in the boot menu. The boot partition you use should have priority 0 and for the currently unused ones it doesn't make any difference if they have different boot priorities (-1 ... -127) or all the same one (-1).
OK, restriction is possibly the wrong word, but there is no documentation of these default uses by the OS. I couldn't find any details about +5 for floppies, or +10 for optical drives, or even using negative numbers for my hard drives. That's totally new to me, after 20+ years of using an Amiga. At the end of the day, it is all about documentation, and whilst I agree that side of OS development is not the fun side it needs to be done, and these default OS boot priorities should really be in it.
I want to go back to my OS4.1 installation, but whilst I am changing the boot priority of OS4.1, would I be better to set them all to negative numbers?
Just to pick your brains. What are those!? IIRC, I couldn't bootup OS4pre off the CD, back in July, 2004! The reason was '-127' was the preset for boot priority of the HD from pre-install. Well, that didn't work; you can't have a bootup priority greater that the CD ( by way of 'twos complement' )! Roy Leath , my favorite system analyst, suggested '+5' for HD boot priority. So, I've lived with that setting as the bootup HD. It's never conflicted with CD bootups until OS4.0 'final.' I couldn't get the CD identified using sii0680IDE.device? That was a good kick in the zero! I eventually tried the Sys:Prefs/Uboot/sii0680 setting devices. The "automatic" settings were skeptical. I changed them to device names and everything was corrected. Maybe my 'Adaptec Ultra ATA' card didn't like the 'automatic' definitions? What is your IDE device? I'm sure that's a factor.
I want to go back to my OS4.1 installation, but whilst I am changing the boot priority of OS4.1, would I be better to set them all to negative numbers?
Set the OS 4.1 partition boot priority to 0, the others to -1.
IIRC, I couldn't bootup OS4pre off the CD, back in July, 2004! The reason was '-127' was the preset for boot priority of the HD from pre-install. Well, that didn't work; you can't have a bootup priority greater that the CD ( by way of 'twos complement' )!
-127 should work, only -128 isn't supported and using it disables booting for the partition.
IIRC, I couldn't bootup OS4pre off the CD, back in July, 2004! The reason was '-127' was the preset for boot priority of the HD from pre-install. Well, that didn't work; you can't have a bootup priority greater that the CD ( by way of 'twos complement' )!
-127 should work, only -128 isn't supported and using it disables booting for the partition.
ISTR, processors do a 'twos complement' of the data to set the processor flags Carry, Plus, Minus, Negative, Zero, Overflow , true, false. The coder decides what to do from the data AND flag condition. Isn't this what happened: ( 128 < +10 )= false, don't bootup HD); or WAIT() to overflow clears? After the install, the system would not bootup. If I tried RESET, nothing but blackscreen. So, '+5' boot priority was suggested and that solved the problem; ( +5 < +10) = true, bootup HD). Am I misinterpreting the process using the bootup floppy/CD default value =+10 ?
No, -127 + (-1) = -128. There is no +128 in signed 8 bit integers, the range is -128 ... +127.
Oops, here come my favorite nightmares: Yes, but 128 must exist before -128 because of signs. The other nighmare is -0 must exist too.
http://www.vb-helper.com/tutorial_two ... ment.html#PositiveNumbers Two Weird Cases There are two weird cases that arise with twos complement... Because the leftmost bit in 10000000 is 1, the value is negative. When you invert it and add 1, you get 10000000 which is the binary representation of 128 so the original value must represent -128...
... The second weird case is zero. The twos complement of 00...00 is 11...11 + 1 = 100..00. When you drop the leftmost bit (which extends past the bit number B), you get 00...00, which is what you started with. This is kind of nice because it means -0 = 0. It also means there is only one value of 0 in twos complement (recall that sign-magnitude and ones complement have two values for 0).
------------------------------------------------------------ If it doesn't work there is a bug somewhere. Yes, in the conditional compiler, I would guess.
Set the OS 4.1 partition boot priority to 0, the others to -1.
No, -127 + (-1) = -128. There is no +128 in signed 8 bit integers, the range is -128 ... +127.
Oops, here come my favorite nightmares: Yes, but 128 must exist before -128 because of signs.
No. The nice thing about twos complement is that you don't need special signed operators, and don't have to convert between signed and unsigned for calculations, but can use the same ones as for unsigned integers: %10000001 (-127) + %11111111 (-1) = %10000000 (-128).
Quote:
If it doesn't work there is a bug somewhere. Yes, in the conditional compiler, I would guess.
With a compiler that broken you couldn't produce any working executable, and boot priorty -1 would fail already.