Oberon #04: Hardware: Transitioning to 3.5' Disks on ZX Spectrum

M.M.A/SPEED CO.

Have you noticed how the beloved "five-inch" disks have become more expensive lately? Ah... There are none for sale in your city at all! The crisis, the crisis is coming.....

In such conditions, the slow but inevitable transition to "three-inch" disks and drives is unavoidable. The connection schemes for these wonderful devices have been described multiple times in the literature, but there are still some unaddressed "around three-inch problems." One of them is clarified below by our correspondent.

----------------------------------------
╔=====================================╗  
║         INSTALLATION  FDD  3.5'        ║  
╚=====================================╝  

If you are reading the ONLINE newspaper, you may have noticed that in many cities of the Union, FDD 3.5' has started to be installed on SPECTRUM. Recently, about a month ago, I installed such a floppy drive for myself. The impressions are colossal!

Regarding the operation of the FDD 3.5':

1. Works with 720kb and 1.44mb disks (with a sealed high-density window). So far, I haven't had a single failure with these disks (NASHUA MF2-DD 720kb, TDK HD 1.44mb).
2. Although the rotation speed is the same as that of the 5.25, it reads, in my opinion, a bit faster.
3. The disks do not crumple or bend (unless you bite them).
4. Only +5v is required for power.
5. I hope that soon a new TR-DOS firmware will appear that supports the high-density mode of 1.44mb.
[OBN: It seems that this will not happen, as the issue is not only about the firmware.]

On my PROFI 3+, I encountered only one problem. Some programs launched from drive B during operation refer to drive A. And if you have a 3' on B or C, you will not be able to run many programs from it (in particular, most domestic developments with non-standard formats or proprietary protection!). And in case your drive A suddenly fails, it will be quite inconvenient to constantly execute the command TR-DOS A>*"b" to switch to the working drive.

The solution is this: you need to install a switch so that you can change drive A between FDD 5.25' or 3.5'. According to the scheme below, only one switch and three jumpers are needed for PROFI.

            ╔===╦======╦======╗           
            ║▒▒▒║ ON   ║ OFF  ║           
            ╠===╬======╬======╣           
            ║ A ║ 5.25 ║ 3.5  ║           
            ║   ║      ║      ║           
            ║ B ║ 5.25 ║ 5.25 ║           
            ║   ║      ║      ║           
            ║ C ║ 3.5  ║ 5.25 ║           
            ╚===╩======╩======╝           



On many computers, the disk output is made on K1SSЛН2(ЛА13). In such cases, the switching can be done as shown in the diagram (the diagram is provided for SCORPION).

We do the same in the case of PENTAGON. The modification consists of installing a switch, a resistor, and the microchip K1SSЛПS.

DDб5 5       4┌--┐  DDб8 5SSЛА13         
-┬---X-----┬--┤ЛА│6         1┌--┐        
 │         │ 5│  О-----------┤ЛА│3  A    
 │ ┌--┐    ├--┤13│          2│  О----    
 └-┤ЛП│    │  └--┘        ┌--┤13│        
   │  ├----┤       MOTOR  │  └--┘        
 ┌-┤ 5│    │       -------┤              
 │ └--┘    │              │13┌--┐        
 │    /    │              └--┤ЛА│11 В    
 ├---/ -┐  │               12│  О----    
┌┴┐     │  └-----------------┤13│        
│ │    -┴-                   └--┘        
│ │ 10 Ком                               
└┬┘                                      
 │                                       
 │+5v                                    

Regarding modifications to computers such as SCORPION, PENTAGON, PROFI, ATM, etc., you can contact me personally on Sundays at the Book Market in Samara (on the territory of the Hippodrome).             

                           Yudin Igor     
                           St.Zagora 92-34

-════════════════════════════════════════                 * * * *                  

LAST EDITION: 21.05.97                    
MUSIC ВУ    : VISUAL/MS/XTM

Contents of the publication: Oberon #04

• From the Editorial
  This editorial discusses the legal 'charges' against the creators of Oberon #4 as a humorous narrative, highlights the challenges faced in publishing this issue, and announces a potential hiatus for the magazine.
• Scroll
  Analysis of the game 'Chaos' by Julian Gollop. Simplified gameplay mechanics and strategic elements. Description of creatures, spells, and tactics.
• Scroll - Unbeliever
  Description of a mathematical game for ZX Spectrum where players collect formula symbols while navigating gears.
• Scroll - M.M.A
  Discussion of 'Doc the Destroyer', a unique fighting and adventure game for ZX Spectrum. The article covers controls, character customization, and game mechanics. Compatibility issues on different ZX Spectrum models are also addressed.
• Overview - M.M.A
  The article provides a review of games for ZX Spectrum, including KOMANDO 2, WRESTLING SUPERSTARS, TAG TEAM WRESTLING, and CAPTAIN PLANET. It highlights the features, graphics, and gameplay of each game, noting both strengths and weaknesses. The review concludes with recommendations and comparisons to other platforms and games.
• Overview
  Overview of various ZX Spectrum games, highlighting their unique features, gameplay mechanics, and design elements. Includes critique on sound effects, graphics, and technical issues. Discusses games like 'Stryker in the Crypts of Trogan', 'Phileas Fogg's Balloon Battles', and 'Survival'.
• Overview - Alex Noman
  The article reviews games for the ZX Spectrum, including BOOVIE, MOTOR MASSACRE, SOCCER PINBALL, and HUXLEY PIG 1 & 2. Each game is detailed in terms of gameplay, graphics, and unique features. The discussion includes comparisons to other games and highlights specific technical aspects.
• Review
  A review of various games, including Little Computer People and Lost Caves, highlighting their features and versions. It also discusses 75Occ Grand Prix by Codemasters with its limitations. The article provides insights into game mechanics and versions.
• Review
  Detailed review of various assemblers like Alasm 3.8, TASM 4.12, and others, highlighting their features and shortcomings.
• About Everything
  Announcement of the creation of the SamZxNet network in Samara and the challenges of setting it up with HAYES modems. Explanation of the modems' power requirements and potential difficulties. Invitation for technical advice from experienced readers.
• About Everything
  Description of travel to ENLIGHT'97 and meeting various demoscene participants. Observations of event organization and issues. Insights into participant experiences and scene discussions.
• About Everything
  Report on the second day of ENLIGHT'97: events, challenges, and reflections. Describes voting results and organizational difficulties. Highlights future prospects for Spectrum demo parties.
• About Everything
  The article features reader feedback on Oberon #04, critiquing design and content choices and discussing issues with software protection and game enhancements.
• About Everything
  Discussion of the adventure game KAYLETH with gameplay tips and advice. Includes a game dictionary and suggestions from the author and their team. Calls for a local artist for future RPG development.
• About Everything
  Reflection on the closure of the 'ZX-REVIEW' magazine and the adaptation of its article for 'Oberon'. Discussion on the development of ultra-short boot loaders. Optimization techniques for writing one-sector boot loaders on ZX Spectrum.
• About Everything
  Exploration of amateur contributions to electronics, music, and computing history, highlighting figures like Faraday and Babbage. The evolution from handmade instruments to personal computers. Discussion on jazz, blues, and rock'n'roll's informal origins.
• About Everything
  The story of Lieutenant Edward Roberts' journey from radio kits to creating the first PC, the Altair 8800, overcoming skepticism and challenges.
• About Everything
  The article explores the rise and evolution of the computer industry, highlighting the transformation from passionate hobbyists to corporate dominance by giants like IBM and Microsoft.
• About Everything
  An exploration of Sir Clive Sinclair's project after selling the Sinclair brand, detailing the features of the Cambridge Computers Z88 laptop.
• About Everything
  Discussion of software market problems in 1997 for ZX Spectrum, highlighting lack of new software and user reluctance to pay.
• Announcement - M.M.A
  Announcement of 'Black Raven' game by V. Mednonogov, focusing on gameplay, technical challenges, and upcoming features.
• Announcement
  Discussion of the decline in ZX Spectrum development, reviews of new games and utilities, and announcements of future projects.
• Educational Program
  The article provides an overview of FidoNet, a non-commercial computer network often considered the predecessor of the Internet, detailing its origins, growth, and unique cultural aspects.
• Hardware
  Instructions for connecting the 'ALEGRO' modem to computers with normal port #FF, detailing hardware modifications required for proper signal handling.
• Hardware
  Connecting Hayes-compatible modems to ZX Spectrum, focusing on Scorpion and Pentagon models, detailing hardware modifications. Specific instructions for internal port blocking and signal alignment provided. Step-by-step process and technical intricacies explained.
• Hardware
  Discussion of the transition from 5.25' to 3.5' floppy disks for ZX Spectrum, including installation issues and solutions for compatibility with existing software.
• Let's Feast
  A satirical story about a Rabbit who lost his house to a cunning Fox and how a Rooster helped him reclaim it.
• Let's Gourmet
  A humorous tale about Malysh and Karlson's adventures with technology, drawing parallels between computers and everyday life, culminating in a comic mishap with an AMIGA computer.
• Advertising
  Article discusses free advertising policy of Oberon, catalog of programs and hardware for ZX Spectrum, and adventure game engagement.
• Advertisement - Kano
  Promotional campaign by Magic Soft and RPSG in Russia for Amiga multimedia computers, offering exhibitions, sales, and consultations. They highlight Amiga's advantages over other systems, describe various models, and provide price lists. Collaboration with 'Computers for Population' for distribution and services.