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linux/Documentation/ez.txt (c) 1996  Grant R. Guenther <grant@torque.net>

This file documents the ez driver for the parallel port versions of 
SyQuest's EZ135 and EZ230 removable media disk drives.  
        
Special thanks go to Pedro Soria-Rodriguez for his help testing 
the EZFlyer 230 support.

The drive is actually SyQuest's IDE product with a ShuttleTech 
IDE <-> parallel converter chip built in.

Before attempting to access the new driver, you will need to
create some device special files.  The following commands will
do that for you:

                mknod /dev/eza  b 40 0
                mknod /dev/eza1 b 40 1
                mknod /dev/eza2 b 40 2
                mknod /dev/eza3 b 40 3
                mknod /dev/eza4 b 40 4
                chown root:disk /dev/ez*
                chmod 660 /dev/ez*

You can make devices for more partitions (up to 15) if you need to.

You can alter certain driver parameters on the LILO or LOADLIN 
command line.  The general syntax is

		ez=base[,irq]

where base is the base address of the parallel port you want to use 
and irq is the interrupt number for that port.   By default, the 
driver uses the ports at 0x378 and irq 7.  You can disable the 
interrupt by specifying it as 0.  For example, to run the driver 
on port 0x3bc without an interrupt, you would append the following 
to the LILO command line:

		ez=0x3bc,0

If you have configured the driver as a loadable module, you can 
adjust these parameters on the insmod command line using the 
variables ez_base and ez_irq.  For example:

                insmod ez ez_base=0x3bc

The driver can detect if the parallel port supports 8-bit
transfers.  If so, it will use them.

The driver can be used with or without interrupts.  If an IRQ
is specified the driver will use it - if it can. If the irq 
number is set to 0, an alternative, polling-based, strategy 
will be used.  Polling consumes more CPU time, but may be more 
stable on some systems.

If you experience timeout errors while using this driver - and
you have enabled interrupts - try disabling the interrupt.  I
have heard reports of some parallel ports having exceptionally
unreliable interrupts.  This could happen on misconfigured 
systems in which an inactive sound card shares the same IRQ with 
the parallel port. (Remember that most people do not use the
parallel port interrupt for printing.)

It would be advantageous to use multiple mode transfers,
but ShuttleTech's driver does not appear to use them, so I'm not
sure that the converter can handle it.

It is not currently possible to connect a printer to the chained
port on an EZ drive and expect Linux to use both devices at once.
If you need to do this, build both the ez and lp drivers as modules
and load one or the other as required.

When the EZ230 powers on, the "standby timer" is set to about 6
minutes:  if the drive is idle for that length of time, it will
put itself into a low power standby mode.  It takes a couple of
seconds for the drive to come out of standby mode.  So, if you
load this driver while it is in standby mode, you will notice
a "freeze" of a second or two as the driver waits for the EZ230
to come back to life.  Once loaded, this driver disables the
standby timer (until you next power up the EZ230 ...)

Keep an eye on http://www.torque.net/ez135.html for news and
other information about the driver.  If you have any problems
with this driver, please send me, grant@torque.net, some mail 
directly before posting into the newsgroups or mailing lists.