atapicam(4) [debian man page]
ATAPICAM(4) BSD Kernel Interfaces Manual ATAPICAM(4) NAME
atapicam -- CAM XPT (transport) module for ATAPI devices SYNOPSIS
To compile this driver into the kernel, place the following lines in your kernel configuration file: device scbus device ata device atapicam Alternatively, to load the driver as a module at boot time, place the following line in loader.conf(5): atapicam_load="YES" DESCRIPTION
The ATAPI/CAM module allows ATAPI devices (CD-ROM, CD-RW, DVD drives, floppy drives such as Iomega Zip, tape drives) to be accessed through the SCSI subsystem, cam(4). ata(4) and scbus(4) must be configured in the kernel as well. The SCSI target drivers (cd(4), da(4), or st(4)) can then be used to access the devices. The generic passthrough device, pass(4), can also be used to send SCSI commands directly to the devices through the CAM API. A separate CAM bus is created for each ATA bus in the system. On each of these buses, target ID 0 is assigned to the master device, and ID 1 is assigned to the slave (provided they are ATAPI devices). IMPLEMENTATION NOTES
Some SCSI commands are intercepted by the driver, and undergo special processing in order to work around limitations of ATAPI devices. Such limitations can be consequences of the ATAPI specification. For example, ATAPI devices do not implement the 6-byte versions of MODE_SELECT, MODE_SENSE, READ, or WRITE. They can also be common bugs, such as hanging when queried for extended INQUIRY information. EXAMPLES
device ata device atapicam device scbus device cd device pass Add the atapicam driver to the kernel. camcontrol devlist Print the list of all devices available through CAM. mount -t cd9660 /dev/cd0 /mnt Mount a CD-ROM from an ATAPI CD-ROM drive (the command above assumes that the ATAPI drive is the only CD-ROM unit). SEE ALSO
ata(4), cam(4), scsi(4), atacontrol(8), camcontrol(8) HISTORY
The ATAPI/CAM driver first appeared in FreeBSD 4.8 and FreeBSD 5.0. AUTHORS
The ATAPI/CAM driver was written by Thomas Quinot <thomas@FreeBSD.org>. BUGS
atapicam and ATAPI-specific target drivers (acd(4), ast(4), and afd(4)) can be configured in the same kernel. Simultaneous access to the same device through the SCSI generic drivers and the ATAPI-specific drivers may cause problems and is strongly discouraged. BSD
October 22, 2009 BSD
Check Out this Related Man Page
atapi_ide(7) Miscellaneous Information Manual atapi_ide(7) NAME
atapi_ide - Interface for ATAPI or IDE (PC) devices SYNOPSIS
PCI bus CMD/Acer ATAPI/IDE adapter: bus pci0 at * bus ata0 at * controller scsi0 at ata0 slot 0 controller scsi1 at ata0 slot 1 PCI bus Cypress ATAPI/IDE adapter: bus pci0 at * bus ata0 at * bus ata1 at * controller scsi0 at ata0 slot 0 controller scsi1 at ata1 slot 0 PCMCIA bus ATA/IDE disk card: bus pcmcia0 at * bus ata0 at pcmcia? controller scsi0 at ata0 DESCRIPTION
Devices commonly known for their use on PC devices as ATA or IDE devices are supported using the SCSI CAM device driver. The ATA standard has also been expanded to include what are known as ATAPI devices. The SCSI CAM device driver is also used for those disks and CD-ROM devices. These devices may also be known under the names EIDE, ATA-2, Fast-ATA, or Ultra-ATA. Beacuse the ATA/IDE standard was not developed until after many of the devices that used this standard were produced, there are many devices which do not strictly comply with the standard. While it is possible some industry standard devices may appear to work, it is also possible they will cause hang or data corruption cases when used under more stressful situations. For this reason, it is recommended that only the supported devices be used. These devices have been tested and are certified for correct operation. ATAPI/IDE controllers allow the connection of two devices. These two devices are known as the master device and the slave device. If only one device is connected, that device must be the master (slave-only configurations are not supported). When used by the SCSI CAM device driver, the IDE master device is assigned SCSI id 0 for that controller. The slave device is assigned SCSI id 1 for that controller. No other SCSI ids are assigned on that controller. Most ATAPI/IDE adapters contain two channels (known as the primary and secondary). Each of these channels may contain their own master and slave devices. Therefore, a dual channel ATAPI/IDE controller may contain up to 4 devices (a master and slave pair on each channel). These 4 devices are then accessed as SCSI id 0 and 1 on each channel. Many SCSI operations translate perfectly for use on IDE. For example, read and write operations are the same. However, many SCSI disk mode pages are emulated by the IDE device driver. For example, you can display the SCSI inquiry mode pages using the following command: % scu show inq pages pages are created by the device driver to contain the long (full IDE) form of the device name, serial number, revision, and the operational modes of the device. Only a shortened version of this information is available with the standard SCSI inquiry command. Note also that the following command: % scu show pages Shows that the SCSI mode pages contain only partial information. Only that informa- tion (such as geometry) that the drive reports to the system is able to be reformatted into these emulated SCSI mode pages. Much of the information (such as RPM) is simply not available from the drive, and therefore not accurately reported. ATAPI devices are much more closely related to SCSI devices, and as such contain their own mode pages. Therefore, for these devices, the mode page values reported are those from the device, and no emulation is involved. ATAPI tape devices are not supported at this time. FILES
/dev/disk/dsk??? /dev/disk/dsk??? RELATED INFORMATION
SCSI(7), rz(7), and disklabel(8) delim off atapi_ide(7)