On 03/09/2010 09:51 AM, Darryl Miles wrote: > Andrew Thomas wrote: >> 1.33c gave me the option to boot from a CF card - as it would with 1.33. > > I'm not sure I understand your response. > > > The only storage I have installed is the CF card. I have it working > providing I make the /boot partition fit on the first cylinder (the > imaginary first cylinder when you convert to CHS geometry). So there is > no doubt that plain 1.33 supports a CF card for booting. > > The only background reading I can find is that 1.33b/1.33c were produced > in response to some issues/workaround with hardware production. Which > might explain why no release notes since only those affected need to > upgrade ?
1.33c solved the detection problem I was having with transcend 16GB cf cards, that that was repeatable given that I have more than one 5501 that we upgraded. > Nowhere has it been stated that any fixes/changes have been made in > 1.33c that affect this particular problem. > > > Infact I should ask, does anybody have a > 8Gb Compact Flash with GRUB > working without the 1 cylinder restriction ? > > The 8Gb limit comes from the C/H/S geometry returned by comBIOS for my > flash being 1946 cylinders, 255 heads, 63, sectors. This is larger than > the 1024 cylinder limit. > > That limit for the C/H/S range of 0/0/1 to 1023/254/63 is 1024*255*63 > sectors or 8225280 KiB or 8032.5 MiB or 7.8442 GiB or 8.422 Gb. So as > flash maybe rated in Gb not GiB it needs to be larger than 8 Gb to be > relevant. > > I do not have smaller CF cards to test and see what C/H/S geometry > net5501 returns for say a 4Gb or 2Gb or 1Gb flash card. It is possible > due to that geometry choice the particular bug I am being hit with does > not show itself. > > > > Also does comBIOS 1.33 (and later versions) provide these BIOS interfaces : > > > [INT 0x13 AH=0x41 BX=0x55aa] is used by GRUB for LBA mode check, it > expects a return of [Carry flag reset, BX=0xaa55] on return to indicate > LBA mode is supported (i.e. function AH=0x42 is supported for LBA mode). > > [INT 0x13 AH=0x42 various other registers used] is used by GRUB for > LBA read sectors from disk into memory. > > > > Thanks, > > Darryl > _______________________________________________ > Soekris-tech mailing list > [email protected] > http://lists.soekris.com/mailman/listinfo/soekris-tech > _______________________________________________ Soekris-tech mailing list [email protected] http://lists.soekris.com/mailman/listinfo/soekris-tech
