Zhelezyachki - an overview of some modern controllers for use with external storage media for the ZX-Spectrum.

<b>Zhelezyachki</b> - an overview of some modern controllers for use with external storage media for the ZX-Spectrum.

   A brief overview of some contemporary

    controllers for use with external
 storage media for the ZX-Spectrum

(C) Gartfelder Denis


  In this short review, I tried to collect information on the 
new controller for use with external storage media that can be 
connected to the ZX-Spectrum. The described devices have a 
number of distinctive features that make them and ended up in 
this review: 

1. They are designed by Western manufacturers and little known 
among the "Eastern" (former Soviet) spektrumistov; 

2. They are not products of industrial production, their device 
is not normally very complicated and they can be collected 
independently; 

3. They use modern common storage media and built
available on the microcontroller, which facilitates their 
assembly; 

4. They are open and constantly improves the projects, and all 
information about them available to everyone. 


  Much of the material for the review was
taken me from the English Spectrum-Journal
"ZX FORMAT" (namesake of domestic electronic edition) and was 
supplemented with information from the sites of the developers 
themselves. Using this opportunity to advise users of 
English-speaking and having the opportunity to use the Internet 
to get acquainted with this wonderful magazine to: 


      http://www.cwoodcock.co.uk/zxf


  Just want to warn readers that
I have to put it mildly, not expert
iron and Spectrum periphery. Therefore,
ask advanced in these matters readers not much kick me 
(mentally) because the use of inaccurate translations of 
technical terms or any more significant errors in the article. 
After all, her goal is not transfer of technical data and

disclosure principles of the devices, and
bring information about their existence
to the attention of those people who do not know
English or are unable to
read the foreign press.


      Flash Disk for ZX

Developer: Roelof Koning (Roelof.Koning @ 12move.nl)


  Using CompactFlashCard volume
128 Mb instead of the hard disk.


  Memory card is inside
computer, connect the wire to the address bus (A7, A8, A14, 
A15), the data bus, signals / RD, / WR, / IORQ. CFC Construction

requires no additional interface (1 resistor, 2 diode), one wire
end connected to the bus, while others are just stuck in the 
female-socket card. 


  Operation is carried out through the IN / OUT on the 
following ports: 



      A7 A15 A14 A8 Port Action


       0 0 0 0 127 read / write of an even byte

       0 0 0 1383 read / write odd byte

       0 0 1 0 16511 Sector count

       0 0 1 1 16 767 Number of sectors

       0 1 0 0 32 895 Number of cylinder (Jr. B)

       0 1 0 1 33 151 Number of cylinder (item B)

       0 1 1 0 49 279 head

       0 1 1 1 49 353 Status / Command



  Sector size - 512 bytes read / write operations occur through 
sektorbufera. 

  Since the card with 16-bit access,
information is divided into relatively "even" and
"Odd" byte. Once the port
127 were produced reading "even" bytes into it copies the value 
of the "odd" port 383. Registers are responsible for rates head 
/ cylinder / sector also support logical addressing (Mode

LBA).

  Some (basic) commands:



    Code Team


    # EC Identification of the device (reading from sektorbufera

        512 bytes of information on the manufacturer)

    # 20 Reading sector

    # 30 Write sector



  The value of bits in the status register:



              Bit Flag Meaning


                0 ERR Error

                1 0 Not used (always 0)

                2 CORR necessary data correction

                3 DRQ expected data

                4 DSC Ready

                5 DWF write error

                6 RDY Ready to take command

                7 BUSY Busy



  In the normal state should be included
only 6 and 4-th bits.

  Special software
to work with the card does not exist, the use of registers 
suggests that writing routines read / write from card presents 
no difficulty. Below is a sample program in BASIC-e, which 
reads the card placed there sektorbufera team-identifiable 
information: 


  10 CLEAR 39999: LET T = 40000

  20 IF IN 49535 <> 80 THEN STOP: REM Check availability maps

  30 OUT 49535,236: REM sends a command to identify the # EC

  40 POKE T +1, IN 127: POKE T, IN 127: REM Reading "even" and

       "Odd" byte of sektorbufera

  50 IF IN 49535 <> 80 THEN LET T = T +2: GOTO 1940: REM cycle 
will 

       continue for as long as the card will not give a signal

       ready (after reading all 512 bytes)

  1960 REM output the read information

  70 FOR F = 40000 TO 400512

  80 PRINT F; ""; PEEK F, CHR $ PEEK F AND PEEK F> 31

  1990 NEXT F


  In this example, line 50 not checking for errors that occur, 
simply expected state of "ready." In reality, however, may 
experience various errors, and they need to track. 


             ZXCF

Developer: Sami Vehmaa (user.tninet.se/ўvjz762w /)


  Using CompactFlashCard as a universal drive.


  Unlike the previous version, in which the map acts as a
"Zhelezopodkreplennogo ramdisk"
This development is a complete controller for use with CFC. 
Accordingly, complicated and circuit portion, so that the 
category of "do- himself, "this development can be attributed 
to the large interference. 


  This system allows you to work in the operating system 
ResiDOS or in specially adapted +3 e for Amstard ZX Spectrum

3 + (both the OS developer - Garry Lancaster). Nevertheless, 
the controller will work on any Sinclair-compatible machines. 
ResiDOS can not work with directories, but it can create 
partitions (partitions). The controller also allows the use of 
multi-(16 Kb) access to built-in RAM 512 or 1024 Kb.



  The controller is connected to the system
jack (its dimensions, he somehow looks like a tombstone:)). 
When you click on NMI button upload their own Task

Manager, one of the notable features
which is the ability to make snapshots of memory (up to 16 
images in 48 mode with built-in memory in

1 Mb), switch between them and save them, both on the 
CompactFlash-card and in memory of the device. Since the power 
ZXCF autonomous, it can store information in its internal 
memory as much as it will make the battery (which will last for 
3 years and then have to apply some skill with a soldering iron 
to replace it). You can download the game, go through several 
levels, take a picture, save it in memory of the device, turn 
off the computer and forget about it for a couple of months and 
then turn and continue the game from the very

the place where she was the last time
preserved. Use as a device for saving maps CFC allows
perpetuate their playing record:).


  The developer notes that the device is tested with several 
types of CFC-drives of different capacities from different 
manufacturers, and not all of them earned. 


  The page developer can find necessary for the independent 
production of the device files (PCB Boards and concept).



            YABUS.ZX

Developer: Jarek Adamski (zx@yarek.com)


  Universal interface for connecting
external devices.


  Connected to the system connector of a miniature controller 
with two connectors, allowing you to connect and run in 
parallel with different specialized modular devices (YAMOD). A 
distinctive feature of the modules is their 
zhelezonezavisimost; YABUS can be connected to the ZX 81, ZX 
Spectrum, Timex, SAM Coupe, MSX, Amstard CPC. Besides the 
version YABUS.ZX, the developer proposes interfaces for Amstard 
ZX Spectrum +3 and Timex, probably will be a version for the 
Commodore Amiga. The development interface that allows 
"parasite" on the PC-hardware. 


  Working with some of the devices available in standard mode, 
but to complete the work recommended special operating systems: 
SRM22QED (Extended version of CP / M 2.2), ZXVGS (operating 
system developed by the author this interface).



  The author has developed the following modules:


Module Purpose

YAMOD.ATBUS IDE-controller that lets you connect HDD, CD
               ROM, CFC. In addition, may carry on board

               Nonvolatile clock with independent power supply 
and 

               can generate an interrupt with a given

               intervals (needed, for example, for the disk
               Dov computers Timex)

YAMOD.EPROG was conceived as a programmer EEPROM and mikrokon
               trollerov 8751, but in essence is a universal
               nym parallel 30-bit port, allowing
               msya communicate with the computer data about the
               tocol ECP.

YAMOD.IDE8255 more simple (less fast) IDE-controller

YAMOD.ZXINPUT Allows you to connect a keyboard and mouse from 
the PC. 

               Also allows you to generate an interrupt, so

               as is done in the SAM Coupe (before each of the

               191 screen lines)

YAMOD.KJ Connection Kempston-joystick

YAMOD.KMOUSE Connection Kempston-mouse (need a mouse on the 
Amiga) 

YAMOD.FDC765A floppy drive controller. The drive can operate in

               two modes: as a ZX Spectrum +3, or as an ISA

               Multi I / O

YAMOD.AY sound module. Additionally completed

               I2C bus, and allows you to connect 8k EEPROM, 
used                the employed operating system ZXVGS


YAMOD. EPLIP Some smart parallel port with FIFO-Buffet
               ramie

YAMOD.8250 serial port (like a PC). Through ZXVGS

               You can work with connected thereto PC-mouse

YAMOD.8211 PC-like printer port

YAMOD.MB02 Port Programmable I / O Connector 8255
               emom DB37 as a disk interface MB-02

YAMOD. PCMOUSE Simple RS-232 PC-mouse with a speed of 1200

               or 19200 bps

YAMOD.SIO For professionals in the radio - allows

               turn the computer into a TNC-modem (if you have 
ku                drink BayCom modem). What is it, I honestly


               speaking, I do not know.

YAMOD.ETHERNET Allows you to connect several network modules

               (Www.embeddedethernet.com), do not require a PC 
for 

               their work. Perhaps it is more expensive

               fun ...



  Unfortunately, this project is commercial, and
developer fails to provide the public
access to basic circuits and devices
its modules. You can buy them from him for quite reasonable 
prices. 

  Additional Information:


    http://zx.yarek.com/dYABUS-en.html


  Info on the operating system ZXVGS:


          http://zxvgs.yarek.com


              zxUSB

Developer: Dave "The Lurker" Mills


  Controller for USB-devices
on the ZX Spectrum.


  Trying to create a working USB-controller to connect to the 
Spectrum-compatible machines of different devices, equipped with

Interface USB, first portable memory drives (USB FlashDrive). 
Controller based on the chips National Semiconductor USBN9603 
allows you to connect one device via a standard USB connector 
to the system bus computer. Perhaps that will be developed 
version for Connection via YABUS.ZX.



  The base address of the controller - # 91. By
additional reprogramming of the controller and write the 
program-handler nonmaskable interrupt NMI can be used to 
control data transmission. Consumed by the connected device 
power disabilities PSU Spectrum (current strength is not more 
than 100mA). 


  Software to work with
device does not currently exist. All the necessary information, 
including Files PCB layout, schematic diagram of the device 
documentation USBN9603, can be found at:


 http://8bitorbust.info/sinclair/spectrum/hardware/zxUSB/.


            ZXATASP

Developer: Sami Vehmaa (user.tninet.se/ўvjz762w /)


  16-bit interface to external drives.


  ZXATASP a 16-bit IDE-controller
based on a programmable module NEC
D8255AC-5, allowing you to connect to a computer hard drive and 
CompactFlash Card. It connects to the system connector and runs 
on all Spectrum-machines from ZX Spectrum 16 without a hardware 
revision computer. Has on board 128/512 Kb of memory, you can 
load to it any flash ROM, select and work with one of the them.



  8255 module features three 8-bit register
(A, B, C) and status register (CWR), which allows to monitor 
the status of ports syazannyh with these three registers:




               Register Port Value


                     A # 009F Byte

                     B # 019F High Byte

                     C # 029F Condition IDE / MEM

                   CWR # 039F control register



  Register CWR allows for switching
read / write registers A and B (case
C is always in write mode):


  OUT 927,146 - switch registers as a result
                bench reading


  OUT 927,128 - switch registers as a result
                bench press record


     The values of the flags register C:



                                    Value

              Bit

                       Non-Latched Latched


                0 A0

                1 A1

                Page 2 A2

                3 / IOWR

                4 / IORD


                5 / CS0 first channel IDE / CS0


                6 Latch clock


                7 / CS0 second channel IDE MEM on / off



  Examples of routines that write / read data through the IDE:


  10 REM Write data to IDE

  20 REM Sets the value of early register bus IDE (D00-D07)

  30 LET DATALOW = 139

  40 REM Sets the value of older register bus IDE (D00-D07)

  50 LET DATAHIGH = 217

  60 REM Switch to record the port

  1970 OUT 927,128

  80 REM Shipment value junior and senior registers

       bus to the appropriate ports

  1990 OUT 159, DATALOW
 100 OUT 415, DATAHIGH
 110 REM Get access to the register state IDE
 120 OUT 671,55
 130 REM Reset all control flags
 140 OUT 671,0


  10 REM Read data from IDE

  20 REM Switch to read from the port

  1930 OUT 927,146

  1940 REM Get access to the register state IDE

  1950 OUT 671,55

  1960 REM Read the values of younger and older registers

       tires from the corresponding pores

  70 LET DATALOW = IN 159

  80 LET DATAHIGH = IN 415

  90 REM Reset all control flags
 100 OUT 671,0


  The device is equipped with a low-capacity memory of 128 or 
512 Kb. Zero memory page contains a boot loader and utilities 
for working with the IDE, the first - a few modified firmware 
ROM. The principle of operation is to be loaded with IDE, and 
then substitute for zero loading page "native" or any another 
ROM (with enough memory to store their few dozen). For this 
purpose the second bit of register C in the set condition, and 
the number memory pages given by bits 0-4 of this

same case:


       OUT 617 (64 + page number)


  To disable this feature using the seventh bit of register C, 
and should be included, and the sixth, and seventh bits and 
bits from zero to four must be Always turn off (and the 
controller properly initialized command OUT 927, 128 or OUT 
927, 146). If this was not to be, then "with the second IDE 
channel can happen anything bad "(quote from the technical 
documentation to device).



  Download to your device firmware
ROM is as follows: in
certain position set the jumpers on the device itself, then the 
device is initialized and configured by register C, then the 
image ROM can be loaded into the memory using POKE 016,383 or 
LDIR. 


           Glossary

I ¤ C - Inter-IC, the communication interface between the inter
      grated circuits.

IDE - Integrated Device Electronics, type

      interface disk drives in

      which the control electronics time
      was placed in the drive, does not require
      buoy special adapter card.

CFC - Compact Flash Card, memory card, it
      bone 1-512 Mb. The interface is sufficient
      but versatile format CF susches
      tvuet many devices - modems, FD
      tokamery, network adapters, GSM model
      Dooley and hard drives. Used

      Some handheld computers.

EEPROM - Electrically Erasable Programmab
      le ROM, electrically-erasable prog
      rammiruemoe ROM.

FIFO - First-In-First-Out, a buffer, from which
      rogo are released on the same
      row, as they did (so called.

      buffer FIFO).

RS-232 - Recommended Standard 232, Industrial
      lenny standard for serial

      compounds, identifies specific

      lines and signal characteristics, study
      the employed controller sequence
      Tel'nykh compounds.

USB - Universal Serial Bus, Universal

      Serial Bus.