Date: Fri, 22 May 1998 14:55:56 -0700 From: Mike Smith <mike@smith.net.au> To: randal@comtest.com Cc: Andrzej Bialecki <abial@nask.pl>, freebsd-small@FreeBSD.ORG Subject: Re: Embeded applications? Message-ID: <199805222155.OAA02699@dingo.cdrom.com> In-Reply-To: Your message of "Fri, 22 May 1998 12:21:52 -1000." <199805222203.MAA07511@oldyeller.comtest.com>
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> 1. Software BIOS emulation, INT 13H. Also identified as Flash File System. > This mean that you can only access the flash through BIOS call interrupt 13H. > Using INT 13H you can specify CHS(cylinder,head,sector) values to access the > flash. It does not have any hardware compatibility with IDE I/O ports or > registers. Since DOS commands rely only on BIOS calls to access hard drives, > this type of emulation works with the standard DOS commands FDISK and FORMAT. > FreeBSD kernel cannot see this type of flash since it cannot call BIOS > routines. (this is the type of flash that is built onto the PC/104 CPU board I > am using) Actually, FreeBSD-current probably *can* talk to this sort of flash disk, although there are some missing components (the disk driver, eg.). Someone with a BIOS-only flash disk would be the perfect candidate to complete this support. > I will try using the rawboot, since I do not need FFS. Technically I do not > have access to FFS anyway as explained above, since I am using software BIOS > flash drive. You can use the normal boot1/boot2 bootloaders, as they have enough FFS support internally to read the kernel. > I still need to figure out once I have the kernel and MFS built. How to > transfer that to the flash drive? I need some kind of program that > can transfer an image to the flash drive using BIOS-INT 13H calls. Write the boot image to a floppy, boot DOS on the target system and use diskcopy. > This would be an alternative. Since I can format the flash drive as a > bootable DOS FAT partition. And put the fbsdboot.exe and a bootable kernel > image in it. And then boot DOS and have autoexec.bat execute fbsdboot.exe on > startup. This wastes (lots of) space. > NOTE: FYI, "FFS" acronyms is used in two ways. > In FreeBSD FFS stands for Fast File System. > In the PC/104 industry FFS stands for Flash File System. > It can get confusing at times... :) Yes. Although the Flash File System extends beyond just the BIOS interface. -- \\ Sometimes you're ahead, \\ Mike Smith \\ sometimes you're behind. \\ mike@smith.net.au \\ The race is long, and in the \\ msmith@freebsd.org \\ end it's only with yourself. \\ msmith@cdrom.com To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-small" in the body of the message
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