Op 29-1-2012 16:19, Bret Johnson schreef: > USBDRIVE provides a device driver, but also provides an INT 13h interface. > There are lots of freely available DOS tools that will work with this type of > architecture, since the USB disk appears to be a simple removable hard drive. > DOS should have been natively supporting sectors other than 512 since the > early 1980's, anyway. > > OTOH, an ASPI driver might make sense for USB CDs and DVDs instead of an > MSCDEX-style driver approach, since ASPI allows for easy writing to disks > instead of just reading. The standard MSCDEX-style drivers aren't set up for > writing.
Traditional SCSI controllers had the following layout: [1] Mass Storage Controller driver (SCSI/ASPI) (providing int13?) [2] Disk controller driver (usually not needed), hooks into [1] [3] CD driver (hooks into [1], thus independent of [2]). LUN-support [4] CDEX-driver (hooks into [4], giving a DOS driveletter) As USB and Firewire are simplified (ahem..) SCSI implementations anyway, various operating systems use SCSI stacks for this. Think IOMEGA used ASPI/SCSI also a lot for their infamous ZIP drives. I think some (Linux-based?) backup software went through ASPI. Most notable are indeed CD-writing software like CDRECORD and WODIM, only requiring [1] to be loaded to talk to a device. Some commercial USB/Firewire CD-drivers might also depend on ASPI. Jack has his own private reasons for not being a fan of ASPI, thus his UIDE driver (PCI IDE/SATA storage and optical disk driver) doesn't implement nor hook into ASPI. I'm not aware of opensource CD-writing software that doesn't require ASPI. My solution in VMware for example has been attaching the physical CD-drive as a SCSI (Buslogic) drive to the virtual machine, then loading the BTDOSM.SYS driver followed by using WODIM. Slightly more convenient/generic might be the ASPI.SYS driver by OAK Technologies. An opensource generic ASPI driver for USB and/or IDE could be a very nice addition. Even if your purpose is 4K sector support :) Bernd ------------------------------------------------------------------------------ Try before you buy = See our experts in action! The most comprehensive online learning library for Microsoft developers is just $99.99! Visual Studio, SharePoint, SQL - plus HTML5, CSS3, MVC3, Metro Style Apps, more. Free future releases when you subscribe now! http://p.sf.net/sfu/learndevnow-dev2 _______________________________________________ Freedos-user mailing list Freedos-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freedos-user
