IS-DOS - users "No4:" Working with electronic drive among the IS-DOS ".

  Category "IS-DOS - users" No 4


      "Working with electronic drive

             among the IS-DOS "

(C) V. Eliseev
,_________________________________________


    Today in our heading "IS-DOS -
users "will talk about how
form correctly ramdisk
how to install it at boot time on various models of 
Spectrum-compatible computers. 

1. What is a "Solid State Disk" and what it is among the IS-DOS.


    Electronic drive system IS-DOS
called a virtual block device, organized in memory paging
Spectrum-compatible computer with a volume of more than 48K of 
RAM. Other words, this is an area of memory is organized so 
that it can be address directly from file shells IS-DOS as an 
ordinary drive. 


     Maybe you think it is strange - why imitate the drive when
he already has - but ramdisk has one huge advantage over
Compared with the drive and even vinchsterom
- A read / write speed commensurate
to the speed of the computer itself.
Using a RAM disk you much
reduce the time required to podgruzku with
drive external commands, utilities, and overlays
application modules. Suffice it once worked with an electronic 
disk and you will "Feel the difference."



     Of course, the contents of the e
disc depends on the amount of memory
Your computer. Typically, the electronic
disk contains the most frequently used programs and system 
utilities, For example tv.com, filecopy.com, delete.com, text 
editor, etc. It is also helpful to keep the configuration there 
system files: extent.txt, extkey.txt and etc.


    The optimum amount of RAM
in which most fully realized
opportunities of electronic drive - 256-512K,
excellent results show computers
with 1 megabyte of RAM, but in the ordinary
128-x Spectrum use in electronic,
or, as it is called, RAM-disk, also gives quite a sizeable 
increase in performance. 

2. RAM disk driver.


    Working with electronic drive in the medium
IS-DOS system organized by
special program, called "electronic driver disk."

    RAM disk driver - a hardware-dependent resident program.
This means that for each type ZX-compatible computers should be
its own driver, making it
hardware features of "transparent" for
system and the user.

    The current system IS-DOS
It supports all major standards of extended memory ZX Spectrum, 
is: 

 1. Standard Spectrum 128 (Pentagon 128
Contact 128 and others) - is used all the memory above 48K, 
which allows you to create RAM disk size of 320 blocks

(80K);

 2. Standard Scorpion (Scorpion 256, Peters 256, KAY 256) - is 
used all the memory above 48K, which allows you to create disc 
with a volume of 832 units (208K), it is possible to use only 
memory over 128K, which reduces the RAM-disk, 512 blocks 
(128K), but allows you to simultaneously use an additional 
buffer 80K when working with copiers filecopy.com,

copy.com, copy25.com etc.

 3. Standard Profi (Profi 1024) - uses all the memory above 
128K, which allows you to create a RAM disk size of 1,536 units 
(384K) for Profi 512 to 3,500 units (896K) for a full 1MB of 
RAM. 

 4. Computers ATM - here is the case
somewhat more complicated due to the fact that addressing 
extended memory in these computers repeatedly changed from 
version to version, which causes some problems when writing 
drivers. Therefore, the existing ATM drivers can be 
successfully operate on a single board and completely

work for everyone else. In connection with the
This driver is written in our ATM
firm in order to provide customers with the necessary technical 
information its board. On computers that use ATM memory above 
128K, which gives 1536 blocks (384K).


 5. And finally, the last one - to the owners of the 48 x PCs 
with the "shadow RAM" addresses # 0000 - # 3FFF (HOBBIT, and 
various homemade), a special driver that allows to create an 
electronic ROM size 64 blocks (16k). This, of course, a little, 
but still better than nothing. Special program-tuner enable

choose port numbers for machines with non-standard connection 
"shadow" RAM. 


    If your machine does not match any of the above
standards, you can order a company
ISKRA SOFT special driver, providing us with the necessary 
technical information on your machine. 

3. Initial creation of RAM-disk.

 3.1 Creating a RAM disk begins, as you may have guessed, with 
a load driver. Drivers of electronic drive

as drivers of all block devices
located in SERVICE \ BLK \ basic kit IS-DOS. To install the 
driver must do one of the following: 

 1. Exit to monitor command line
Key (m) and type the command:


    Q: RES \ set Q: SERVICE \ BLK \ xxxx.blk

where xxxx - name of your driver

 2. Write a text editor and run the team bat-file that contains
line described in paragraph 1

 3. Set the cursor on the name of your driver and press ENTER.


     Since then, drivers have been installed in
system, which can be seen by viewing the domain of drivers with 
programs show.com or eliminat.com.



     Electronic driver disk when installing automatically 
attached to the first free device (most often

With the device, but if you have a third drive or hard drive, 
the driver is installed on another device). See line driver 
block IS-DOS device can be using the utility choose.com, it 
displays List of 8 available in the IS-DOS Device

and in front of everyone - the name of the
his driver. Reinstall the driver
other devices using the utility dev.com.


    Standard RAM disk driver is in memory of 600 bytes. In
Recently the new drivers
significantly reduced (less than 256 bytes)
they differ from the old lack of
internal buffer, which, however, does
does not affect the operation of the system for
except for a single event - save the current system of command 
at sv.com RAM disk, but since such a situation, as well as any 
other related copying the contents into the upper 16K

ramdisk, almost does not occur when working in the IS-DOS, it 
is quite can be neglected, saving 500 bytes in

the main computer memory.


    A few more words about the drivers
e-ROM, developed by
ISKRA-SOFT for different models of Spectrum-compatible 
computers: 

ed_128.blk (04.10.94, 560 bytes) mill
              dard driver for all

              machines with 128K of RAM can be

              used on any ZX

              Spectrum for a

              RAM-disk size of not more than

              80K.


    It must be remembered that the creation of
RAM disk driver that uses the same memory region as an 
additional buffer copiers, so their joint use is not permitted, 
and the above-mentioned buffer before the installation of 
electronic drive must be disabled by the utility in 
copytune.com All copyist (filecopy.com, copy.com, copy25.com, 
from_msd.com, to_msdos.com, from_trd.com. to_trdos.com)


ed128-.blk (24.04.95, 169 bytes) decreases
              weighted version of the driver

              Spectrum 128 and other small
              tires with at least 128K.

ed_scorp.blk (04.10.94, 533 bytes) mill
              dard driver for the computer
              ters Scorpion and is compatible
              Mykh with computers Pe
              ters 256 and KAY 256. He used
              uses 128K of memory does not

              in the configuration

              Spectrum 128, which allows

              avoid conflict between

              electronic drive and an additional
              ditional buffer is copied
              schikov.

edsco +. blk (02.09.94, 546 bytes) alter
              native driver

              computers that are compatible with

              standard Scorpion. He used
              uses all the memory above

              48K and allows you to create

              drive up to 208K. EU
              naturally, want to turn off
              of buffer copiers.

edsco-.blk (29.04.95, 195 bytes) decreases
              weighted version of the driver

              ed_sco +. blk

ed_profi.blk (01.11.93, 528 bytes) driver

              for computers with Profi

              RAM size up to 1MB. He used
              uses only the memory, not

              in the configuration

              Spectrum 128, which allows

              quietly enjoy the Buffet
              rum copiers and gives

              the ability to create a disc

              up to 896K, 300

              bytes exceeds the amount of disk space
              you are in the IS-DOS!

edprof-.blk (20.06.95, 178 bytes) decreases
              weighted driver for the Profi.

ed_atm.blk (30.09.94, 538 bytes) driver

              RAM disk, the work
              yuschy on one of the computers
              ditch series ATM, in what

              it is unfortunately still

              could not be established in

              Due to the diversity and
              sufficiently widespread
              The intensity of these computers

              our city.


     In the near future may clarify the situation and creating 
drivers are guaranteed to work on ATM TURBO 2 +, but as long as 
ATM owners can count only for the initial assembly code and 
driver independent refine it for his fee. Spelling

same driver on the reservation is possible only if
availability of technical information on the organization of 
memory in each case. 

ed16.blk (27.06.93, 72 bytes), specially
              exponentially driver for the computer
              ters with "shadow RAM", pos
              it possible to create a 16-kilo
              byte ramdisk

              comes with a tuner

              ed16tune.com, which facilitate
              PECULIARITIES configure address

              port, including the shadow

              page on the various models
              fields of computers.


     In addition, there are some special drivers, such as: 
ed_3.blk Computer Amstrad, ed128rom.blk for

computers that are running IS-DOS, sewn in
ROM, ed128ram.blk for IS-DOS CHIC, etc.


     Of course, all these drivers
You only need one - the one that is designed for your computer.
Its something you'll need to install before you start one of 
the above ways.


 3.2 The next stage - the formation
an electronic drive "system tray"
ie, the recording of the special service information and the 
formation of the root directory. This operation is performed by 
the utility create.com, ie, the same as in diskettes, with the 
only difference being that ramdisk not need to partition at

assistance programs format.com, since this
program performs a specific disk partition at a low level, 
which has no point on the virtual block device.



     Utility create.com can work
in manual mode and the command
command line or bat-file. In the first
If all parameters are set manually
menu in the second - with the help of
special keys. Appearance of
create.com shown in Fig. 1



                      Name: IS-DOS

   Drive: C Double

   Retry: 4 Tracks: 80

   Check: Y Sec Size: 1,024

   Exist: ask boot: no boot

   Parameters Dev Size: 512

   Create Dir Size: 2

   Save Continuous

   Exit Quit


 Fig. A utility create.com



     One of the main parameters in this
stage is the size of the electron
disk blocks defined in the string Dev
Size in the right menu. This value depends
on the amount of RAM your computer and is calculated as follows:

for Spectrum 128,256:


        D = RAM-48 000 \ 256 (1)

for Spectrum 512,1024:


        D = RAM-128 000 / 256 (2)

where D - the required disk size in blocks

    RAM - the total amount of computer RAM


     If you want to Spectrum
256 using an electronic disk with an additional buffer copyist, 
then its size should also rely on the formula (2). Summary 
table sample sizes of electronic drives for

computers with different RAM are given in Table. 1.


                               Table 1

Typical dimensions of electronic drives.



  Model Volume Disk Size

                RAM
home computers (KB) blocks kB

HOBBIT 48 64 16

Spectrum 128
Contact 128 128 320 1980
Pentagon 128

Scorpion 256 832 *) 208 *)
Peters 256256
KAY 256 512 128

ATM TURBO 512 1536 384
PROFI 512

PROFI 1024 3500 896


*) In the numerator - no buffer copiers,
in the denominator - using the buffer.


    When you create a RAM disk the most important, as mentioned 
above, are the size of disk and device name to

is connected to the driver. Other parameters can be left by 
default, but they can be used to optimize several created by 
the disc, saving some memory, which is especially important on 
machines with little RAM. 


     The first step is to set the option "boot" in the right 
menu in the position of "no boot" - this will save you 4 blocks 
occupied by the boot sector, which is absolutely not necessary 
for virtual device.


/ DM, where M - the size of the disk in blocks,

/ CX, where X - the type of root directory:

      "0" - if segmented,

      "1" - if the ongoing,

/ SY, where Y - the size of the root directory in

      blocks,

/ VZ, where Z - flag quality dispersion
      ka, when working with RAM-disk is desirable
      Indeed set to "0",

/ BQ, where Q - the type of boot record, with

      work with the RAM-disk is desirable conditions
      tanovit "2" (without the loaded
      zochnoy records)

/ N - do not recreate the existing disk

/ R - to recreate the existing disk

/ M - ask for confirmation at the intersection
      Creating a disc.


     Examples of call create.com:

for the Spectrum 128:

create RAM /-C / d320 / c1 / s2 / v0 / b2 / m

Scorpion for 256 without the buffer copiers:

create ZX256 /-E / d832 / c1 / s4 / v0 / b2 / r

 3.3 Now that we have created with you
ramdisk is still empty, it is
time to complete its first useful information. In fact, the 
electronic drive You can store anything you like, but

preferable to put on it the most commonly used system utilities
and files, which will greatly speed up your system.


     So, what files are better placed to
ramdisk? The answer to this question
best to build a concrete example. Let's consider the process of 
filling electronic drive for Spectrum 128.



    80 kilobytes - this is quite a bit, so we restrict 
ourselves only to the bare essentials. Assume that the ramdisk 
installed on the device C. Free volume of blank disc is 316 
blocks (320 minus 2 units of system information

and 2 unit root):

1. Copy the root file

   extent.txt, it will speed up the solution
   share of the ENTER key and Zai
   met 2 blocks of disk space:

Q: SHELL \ copy Q: extent.txt C:

2. We will create an electronic disk directory

   SHELL, making it a continuous and setting

   size of not more than 2 blocks (switches / sec and

   / S2):

Q: SHELL \ mkdir C: SHELL / c / s2

3. Copy the directory SHELL most

   important system utilities and configuration
   tion file shell:

Q: SHELL \ copy Q: SHELL \ filecopy.com C: SHELL
Q: SHELL \ copy Q: SHELL \ tv.com C: SHELL

the same run for the files:

extkey.txt, extview.txt, exebat.com,
menu.com, menu.mnu

It takes about 42 blocks on the electronic disk.

4. RES create a directory and write it
file set.com (9 other units):

Q: SHELL \ mkdir C: RES / c / s2
Q: SHELL \ copy Q: RES \ set.com C: RES


    After all this we still have more
261 block of disk space on which we can write a text editor
(File dry.com, ed *. ovr, ed_copy.com,
ed_ext.txt, ed_mac.txt, edit +. com, editor.com, wet.com the 
directory EDIT) - is 99 more units, given the volume and 
directory C: EDIT. The remaining 162 blocks you can

use at your discretion and write back the files that you most
use often.


     Similarly shaped
RAM-disk and in machines with 256 and 512K memory
with the only difference being that the files back
fit much more. Principal
differences have only work with electronic
disk size of 1MB, but this - a little
later.

 3.4 Finally, the last stage of initial formation of an 
electronic drive - appointing him as a "fast" device. This 
operation is performed using the internal command DOS L_Q: 


          L_Q / C

(All capital letters required)


     The system will search all
files on the device first "Q", ie,
electronic drive and just not finding them
there will be access device "S", etc.
, to the drive.


     Of course, this sequence
operations, even if it is to be specified as
bat-file, you hardly want to do
every time you boot the system. K
Fortunately, it is not necessary. Suffice it
time to create an electronic disk manually
then retain its image in the file
for rapid decompression in the electronic
disc. So now we consider this
process in detail.

4. Creating a RAM disk image.


     Once the disk is created, you must run a special utility
sv_image.com, which will save
in a file all the contents of the electronic drive


    The utility runs as follows:

1. At the current panel is opened the drive on

   you'll save an image

   RAM-disk.

2. Run the utility with sv_image.com

   Key / N, where N - the logical name

   device that is

   RAM-disk:


        Q: SERVICE \ sv_image / C


     This command creates a file on the current drive 
image.img, which can then be rapidly decompressed utility 
image.com. It can be renamed, although it is recommended to 
keep expanding img, a sign of a disk image, and put in any 
directory, such as specially created by S: RAM. Incidentally, 
in the img-file is only really busy

disk capacity, excluding the blank area in
end, so the file size depends strongly on the occupancy of 
electronic disk. 


     After that you can easily fit into your autoexec.bat 
commands to install the RAM disk from which the team will need 
only install the driver and unpack the disk image. 


     A fragment of such a file for Spectrum
128 You can see below:

Q: RES \ set Q: SERVICE \ BLK \ ed_128.blk
Q: SERVICE \ image S: RAM \ image.img /-C
L_Q / C


     Since the volume img-file grows
As more RAM-disk, such
files for computers with 512K can reach a half thousand units, 
due to which there is a problem with their placement on

system disk. In this case it is useful
create a special disk with minimal
a set of system files and the img-file
with all necessary utilities. The composition
such a disk should contain the following
Files:

S: extent.txt
S: autoexec.bat
S: SHELL \ exebat.com
S: UTIL \ find.com
S: RES \ set.com
S: SERVICE \ is_dos.sys
S: SERVICE \ con.com
S: SERVICE \ boot.com
S: SERVICE \ image.com
S: SERVICE \ BLK \ ed_128.blk (or other)
S: RAM \ image.img


     After copying all these files
Do not forget to make the disk bootable by
Just in case we recall that this can be done using the 
following sequence of commands: 

1. View the current panel directory

   S: SERVICE

2. Quit pressing "m" in the monitor command
line and type the command:


                con is

                boot

3. Exit the monitor command line
Keys SS + A.


     Now when you boot from this disk
Your Spectrum 512 will automatically decompress the image of an 
electronic drive. 

 5. Now we have to talk only
about the peculiarities of working with electronic drives on 
computers with 1 MB of RAM. As already mentioned above, such a 
RAM-disk can fit an entire disk IS-DOS! Of course, we can not 
afford to ignore such a great opportunity, why specifically for 
users of e-megabyte disks exist Track and copiers acca.com 
adbc.com. 


     Copyist acca.com used if your ramdisk is
Device "C" and boot the system with
drive "A". Copyist adbc.com used if the ramdisk is set to "D", 
and the boot goes well with the drive "A". To copy a floppy 
disk on electronic disk to insert it into the

drive "A", open it on the current panel and call one of the 
above copiers. 


     Then you can assign an electronic drive as a system, 
quick, and the current both for the whole day to forget about 
floppies (What a joy!). 


     Do not forget only at the end of the work to make a 
reverse copy of RAM-disk on a floppy disk using the same

copiers, otherwise all your results
work disappear with the power off.


     The converse holds for copying
using the same programs, only when they are called on the 
current panel to be opened RAM-disk. Another recent observation 
on about the track copiers: the logic of their

work is very original, so it
better represented in the form of a table (see
Table. 2)


                              Table 2

The logic of copiers and acca adbc.


Copyist Channel Receiver

acca.com A C

                    B D

                    C A

                    D B


adbc.com A D

                    B C

                    C B

                    D A



     Well that's all. I hope this short article to dot the
"I" on the issue of working with
Electronic drive in the IS-DOS environment and allow you to 
make your work more convenient and efficient. 


       Good luck to you, dear readers!
_________________________________________