paride.txt

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individual co-ordinates when you load the driver.

For example, if you had two no-name CD-ROM drives both using the
KingByte KBIC-951A adapter, one on port 0x378 and the other on 0x3bc
you could give the following command:

	# insmod pcd drive0=0x378,1 drive1=0x3bc,1

For most adapters, giving a port address and protocol number is sufficient,
but check the source files in linux/drivers/block/paride for more 
information.  (Hopefully someone will write some man pages one day !).

As another example, here's what happens when PARPORT is installed, and
a SyQuest EZ-135 is attached to port 0x378:

	# insmod paride
	paride: version 1.0 installed
	# insmod epat
	paride: epat registered as protocol 0
	# insmod pd
	pd: pd version 1.0, major 45, cluster 64, nice 0
	pda: Sharing parport1 at 0x378
	pda: epat 1.0, Shuttle EPAT chip c3 at 0x378, mode 5 (EPP-32), delay 1
	pda: SyQuest EZ135A, 262144 blocks [128M], (512/16/32), removable media
	 pda: pda1

Note that the last line is the output from the generic partition table
scanner - in this case it reports that it has found a disk with one partition.

2.3  Using a PARIDE device

Once the drivers have been loaded, you can access PARIDE devices in the
same way as their traditional counterparts.  You will probably need to
create the device "special files".  Here is a simple script that you can
cut to a file and execute:

#!/bin/bash
#
# mkd -- a script to create the device special files for the PARIDE subsystem
#
function mkdev {
  mknod $1 $2 $3 $4 ; chmod 0660 $1 ; chown root:disk $1
}
#
function pd {
  D=$( printf \\$( printf "x%03x" $[ $1 + 97 ] ) )
  mkdev pd$D b 45 $[ $1 * 16 ]
  for P in 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
  do mkdev pd$D$P b 45 $[ $1 * 16 + $P ]
  done
}
#
cd /dev
#
for u in 0 1 2 3 ; do pd $u ; done
for u in 0 1 2 3 ; do mkdev pcd$u b 46 $u ; done 
for u in 0 1 2 3 ; do mkdev pf$u  b 47 $u ; done 
for u in 0 1 2 3 ; do mkdev pt$u  c 96 $u ; done 
for u in 0 1 2 3 ; do mkdev npt$u c 96 $[ $u + 128 ] ; done 
for u in 0 1 2 3 ; do mkdev pg$u  c 97 $u ; done 
#
# end of mkd

With the device files and drivers in place, you can access PARIDE devices
like any other Linux device.   For example, to mount a CD-ROM in pcd0, use:

	mount /dev/pcd0 /cdrom

If you have a fresh Avatar Shark cartridge, and the drive is pda, you
might do something like:

	fdisk /dev/pda		-- make a new partition table with
				   partition 1 of type 83

	mke2fs /dev/pda1	-- to build the file system

	mkdir /shark		-- make a place to mount the disk

	mount /dev/pda1 /shark

Devices like the Imation superdisk work in the same way, except that
they do not have a partition table.  For example to make a 120MB
floppy that you could share with a DOS system:

	mkdosfs /dev/pf0
	mount /dev/pf0 /mnt


2.4  The pf driver

The pf driver is intended for use with parallel port ATAPI disk
devices.  The most common devices in this category are PD drives
and LS-120 drives.  Traditionally, media for these devices are not
partitioned.  Consequently, the pf driver does not support partitioned
media.  This may be changed in a future version of the driver. 

2.5  Using the pt driver

The pt driver for parallel port ATAPI tape drives is a minimal driver.
It does not yet support many of the standard tape ioctl operations. 
For best performance, a block size of 32KB should be used.  You will
probably want to set the parallel port delay to 0, if you can.

2.6  Using the pg driver

The pg driver can be used in conjunction with the cdrecord program
to create CD-ROMs.  Please get cdrecord version 1.6.1 or later
from ftp://ftp.fokus.gmd.de/pub/unix/cdrecord/ .  To record CD-R media 
your parallel port should ideally be set to EPP mode, and the "port delay" 
should be set to 0.  With those settings it is possible to record at 2x 
speed without any buffer underruns.  If you cannot get the driver to work
in EPP mode, try to use "bidirectional" or "PS/2" mode and 1x speeds only.


3. Troubleshooting

3.1  Use EPP mode if you can

The most common problems that people report with the PARIDE drivers
concern the parallel port CMOS settings.  At this time, none of the
PARIDE protocol modules support ECP mode, or any ECP combination modes.
If you are able to do so, please set your parallel port into EPP mode
using your CMOS setup procedure.

3.2  Check the port delay

Some parallel ports cannot reliably transfer data at full speed.  To
offset the errors, the PARIDE protocol modules introduce a "port
delay" between each access to the i/o ports.  Each protocol sets
a default value for this delay.  In most cases, the user can override
the default and set it to 0 - resulting in somewhat higher transfer
rates.  In some rare cases (especially with older 486 systems) the
default delays are not long enough.  if you experience corrupt data
transfers, or unexpected failures, you may wish to increase the
port delay.   The delay can be programmed using the "driveN" parameters
to each of the high-level drivers.  Please see the notes above, or
read the comments at the beginning of the driver source files in
linux/drivers/block/paride.

3.3  Some drives need a printer reset

There appear to be a number of "noname" external drives on the market
that do not always power up correctly.  We have noticed this with some
drives based on OnSpec and older Freecom adapters.  In these rare cases,
the adapter can often be reinitialised by issuing a "printer reset" on
the parallel port.  As the reset operation is potentially disruptive in 
multiple device environments, the PARIDE drivers will not do it 
automatically.  You can however, force a printer reset by doing:

	insmod lp reset=1
	rmmod lp

If you have one of these marginal cases, you should probably build
your paride drivers as modules, and arrange to do the printer reset
before loading the PARIDE drivers. 

3.4  Use the verbose option and dmesg if you need help

While a lot of testing has gone into these drivers to make them work
as smoothly as possible, problems will arise.  If you do have problems,
please check all the obvious things first:  does the drive work in
DOS with the manufacturer's drivers ?  If that doesn't yield any useful
clues, then please make sure that only one drive is hooked to your system,
and that either (a) PARPORT is enabled or (b) no other device driver
is using your parallel port (check in /proc/ioports).  Then, load the
appropriate drivers (you can load several protocol modules if you want)
as in:

	# insmod paride
	# insmod epat
	# insmod bpck
	# insmod kbic
	...
	# insmod pd verbose=1

(using the correct driver for the type of device you have, of course).
The verbose=1 parameter will cause the drivers to log a trace of their
activity as they attempt to locate your drive.

Use 'dmesg' to capture a log of all the PARIDE messages (any messages
beginning with paride:, a protocol module's name or a driver's name) and
include that with your bug report.  You can submit a bug report in one
of two ways.  Either send it directly to the author of the PARIDE suite,
by e-mail to [e-mail], or join the linux-parport mailing list
and post your report there.

3.5  For more information or help

You can join the linux-parport mailing list by sending a mail message
to 
		[e-mail]

with the single word 

		subscribe

in the body of the mail message (not in the subject line).   Please be
sure that your mail program is correctly set up when you do this,  as
the list manager is a robot that will subscribe you using the reply
address in your mail headers.  REMOVE any anti-spam gimmicks you may
have in your mail headers, when sending mail to the list server.

You might also find some useful information on the linux-parport
web pages (although they are not always up to date) at

	http://www.torque.net/parport/