@database StatRam.guide

@node MAIN StatRam

                            StatRam 3.1


	@{" Introduction " Link Introduction}
	@{" Installation " Link Installation}
	@{" Configuration " Link Configuration}

	@{" StatRam and PC-Task " Link FixPCTask}

	@{" Removing a volume " Link RemSD0}

	@{" Hints and Tips " Link Hints}
	@{" Questions and Answers " Link Questions}

	@{" Note " Link Update} for users of previous versions of StatRam

	@{" Authors " Link Authors}
	@{" Distribution " Link Distribution}
	@{" Aknowledgements " Link Aknowledgements}

	@{" History " Link History}

@endnode

@node Introduction

StatRam is a recoverable ram drive.
It works on any Amiga using V2.04 or greater of the OS. It handles any
filesystem (either Amiga or foreign, like e.g. CrossDOS(tm)), has ten units
and may be layed out like a floppy disk for quick diskcopies.
It is dynamic, that is it allocates and frees memory as files are copied and
deleted, and is probably the most recoverable ram drive available. Even the
worst system crash will not erase it, as long as the portion of memory where
it resides is not corrupted.
@endnode

@node Installation

This section explains the basic installation, which will leave you with a
working StatRam volume. The setup may be modified to change the volume size
or use different filesystems; refer to section @{" Configuration " Link Configuration}.

	@{" Workbench 2.0 " Link 20Install}
	@{" Workbench 2.1 or later " Link 21Install}
@endnode

@node 20Install "Installation on Workbench 2.0"

- Copy statram.device to DEVS:
- Join the file named "mountlist" to DEVS:Mountlist
- Add the command
   Mount SD0:
  to S:user-startup

- Reboot.
@endnode

@node 21Install "Installation on Workbench 2.1+"

- Copy statram.device to DEVS:
- Drag the icon SD0 to DEVS:DOSDrivers

- To mount the volume, double click on the SD0 icon or just reboot.
@endnode

@node Configuration

You may control various aspects of StatRam volumes:
- Their size
- The filesystem they use
- Which type of memory they use to store the data

These changes are performed modifying some parameters in the mount
information.
If you are using Workbench 2.04, you have to edit DEVS:Mountlist by hand;
otherwise, modify the ToolTypes in the icon contained in DEVS:DOSDrivers.

You may mount up to ten volumes at the same time; to create a new volume,
just duplicate one of the sample entries (SD0 for DOS volumes, PC4 for
CrossDOS volumes), change the UNIT field and modify the other parameters to
obtain the desired result.


Modifiable parameters are:

UNIT
  This is the statram.device unit that the volume shall use. It can be any
  value from 0 to 9.
  @{b}Make sure to change the UNIT field of every mountfile so that there are
  no two volumes using the same unit.@{ub}


HIGHCYL
BLOCKSPERTRACK
  These two determine the @{u}maximum@{uu} size of SD0. The device will dynamically
  allocate memory only when it's needed, growing and shrinking as you copy
  and delete files in it.
  (Note: the dynamic @{i}allocation @{ui}is available for any filesystem; dynamic
  @{i}deallocation, @{ui}however, is available only for Amiga filesystems. Therefore,
  a CrossDOS volume will grow as you copy files in it, but will not shrink
  when you delete them).

  The total size in kilobytes of the volume is (HIGHCYL+1)*BLOCKSPERTRACK.

  @{b}Remember that it is @{u}much@{uu} better to fill the disk than to run out of
  memory. Make sure not to oversize the volume, or you'll get write errors
  when you run out of free memory.@{ub}


  Using appropriate values, you may DiskCopy from floppies to ram, and vice
  versa; this is great for many purposes, like making multiple copies of a
  disk, or preparing distribution disks.

  Appropriate values are:
                            Size   HIGHCYL   BLOCKSPERTRACK
  Amiga Double Density      880K     79           11
  Amiga High Density       1760K     79           22
  CrossDOS Double Density   720K     79            9
  CrossDOS High Density    1440K     79           18


BUFMEMTYPE
  This value determines which type of memory StatRam should use to store
  the volume data. Possible values are:

  1  Use Fast memory first, Chip memory last
  3  Use only Chip memory
  5  Use only Fast memory


DOSTYPE
  (This field is available for AmigaDOS volumes only)
  This tells the system which file system to use. Possible values are:

  0x444F5300  Old File System
  0x444F5301  Fast File System
  0x444F5302  Old File System International
  0x444F5303  Fast File System International
  0x444F5304  Old File System - Directory Cache  (OS 3.0 only)
  0x444F5305  Fast File System - Directory Cache (OS 3.0 only)

  You will most probably leave this field to its default value.
  Note that there is really no point in using the Directory Cache file
  systems on a ram disk - they will actually slow it down.
@endnode

@node FixPCTask

The PC emulator @{i}PC-Task @{ui}by Chris Hames greatly benefits from a ram drive.
StatRam is compatible with PC-Task (just use a suitable mountlist, like the
supplied PC4).

You can even use a StatRam volume as drive A:, for extra-fast boots.

Unfortunately, versions 2.00 through 2.03 of PC-Task have a bug which
prevents them from booting from a fast device like StatRam.
The bug is alredy fixed in the French and German language versions, and will
be fixed in the next release.

In the meantime, we have provided a workaround. The patch is called
FixPCTask. All you have to do is execute it from S:user-startup, and PC-Task
will happily boot from a StatRam volume.
@endnode

@node RemSD0

If you need memory for other tasks, StatRam volumes may be instantly removed
from the system:

  RemSD0               removes the first StatRam unit

  RemSD0 name:         removes the StatRam unit of given name
@endnode

@node Hints "Hints and Tips"

Some people like to completely replace the standard RAM: volume with the
recoverable ram disk. This can be easily done by changing the name of the
mount entry from SD0 to RAM, and adding the following lines at the
beginning of the startup-sequence, before any reference to RAM: (but after
SetPatch):

Assign ENV: SYS:
Assign RAM: DISMOUNT
Mount RAM:

(the Assign ENV: SYS: line is necessary because some versions of Mount
would otherwise pop up a "Please insert volume ENV:" requester. ENV: is
assigned to RAM:ENV later in the startup-sequence).

Now find this line in the startup-sequence:

C:MakeDir RAM:T RAM:Clipboards RAM:ENV RAM:ENV/Sys

And replace it with:
C:MakeDir >NIL: RAM:T RAM:Clipboards RAM:ENV RAM:ENV/Sys
@endnode

@node Questions "Questions and Answers"

Q. I sometimes get read/write errors while WRITING to SD0:.
A. You are probably running out of memory, because the ram disk is too
   large. Lower the HIGHCYL parameter.

Q. I sometimes get read errors while READING from SD0:.
A. This means that the memory used by static.device to store the sector data
   has been corrupted. Three possible causes are:
   - You had previously ran out of memory, and StatRam reported a write
     error. Subsequent accesses to sectors which couldn't be written due to
     an out of memory error cause a read error. To fix the error, you may
     use a disk repair utility like @{i}DiskSalv 2 @{ui}by Dave Haynie (the Validate
     function is the most appropriate).
   - You have used a defective program which has trashed the memory used by
     StatRam to store the volume data.
   - One of your ram chips is broken. Check your memory with a diagnostic
     program. Note: the programs supplied with memory boards often don't
     spot small faults like a single bit not keeping its state.
     Don't think it cannot happen to you! It happened to ME!
@endnode

@node Update

StatRam 3.0 is a completely new program. Even the device name has changed.
Therefore, if you are upgrading from a previous version, delete the old
device (static.device), KillSD0 and the mountlist, and restart installation
from scratch.
@endnode

@node Authors

StatRam was originally based on VD0:, a popular recoverable ram drive by
Perry S. Kivolowitz.

Since then it has been refined and rewritten by :

   Nicola Salmoria
   Via Piemonte 11
   53100 Siena   ITALY

   Internet : MC6489@mclink.it


   Richard Waspe

   Internet : waspy@cix.compulink.co.uk
   CbmNet   : rwaspe@hamlet.adsp.sub.org
   Fidonet  : 2:250/151.40

@endnode

@node Distribution

This software is @{i}FreeWare. @{ui}It is freely distributable as long as the archive
remains intact, and only a nominal fee is charged for its distribution.

This software is provided "AS IS" without warranty of any kind, either
expressed or implied. By using it, you agree to accept the entire risk as to
the quality and performance of the program.
@endnode

@node Aknowledgements

Many thanks to the Beta testers :

    Ian Moran
    Mark Fisher
    Mike Walter
    Steve Loughran
    Bob Adams
@endnode

@node History

Version 3.1

- Fixed problem with the disk compressor Zoom. When uncompressing a .zom
  file over a floppy-like StatRam volume, the automatic memory expunge
  was done too soon, causing data corruption.

- Can now be used with PFS by Michiel Pelt, just set the FileSystem and
  DosType fields appropriately. Automatic memory expunge is not available,
  just like with CrossDOS. The disk will grow as data is written to it and
  never shrink.

- At last, found and fixed the pyrotecnic crash which sometimes occured when
  trying to remount a volume after its blocktable had been overwritten by
  another volume.
@endnode