Archived news from Retro-Kit

An Archimedes A410/1 with 8MB of RAM and more!

Due to the demands of work, it's been quite some since the Retro-Kit site was updated but there's been plenty going on in the Retro-Kit world. Not least of which was the ebay purchase of a rather special A410/1 that came pretty much fully loaded with expansions and upgrades. The machine included an Oak SCSI card, Watford ARM3 processor upgrade, and a Simtec 4-8MB RAM upgrade which is a pretty rare upgrade for these machines.

The Archimedes A410/1 with 8MB of RAM

Interestingly though, this machine is not unique. Indeed it has a twin which is owned by another Acorn collector, Beebmaster.

Find out all about this Archimedes A410/1 and the upgrades that I've added to it since I got it in mid-October. 

Posted on: 10 Nov 2013@23:57:22, updated on: 10 Nov 2013@23:57:22.


AutoVIDC v2.10 released

Download imageAutoVIDC v2.10, the most advanced VIDC Enhancer control software for the Archimedes is now available for download. This release features several major upgrades and fixes to the functionality including:

  • Full support for the Watford Electronics "Super" VIDC Enhancer
  • Fully automated detection of available clocks
  • Further additions to the available SWI's
  • Fixes timing issues when !QTheMusic is playing music before AutoVIDC is initialised
  • Code optimisation keeping the module size under 7KB
  • Fixes output issues with several * commands
  • Fixes an issue with re-enabling RISC OS control of AutoVIDC

The addition of the clock detection routines allows AutoVIDC to cycle through all the available clocks that may be fitted to an Archimedes to determine the available clock speeds. This detection capability together with its supporting SWI (AutoVIDC_ClockAvailable) paves the way for future updates to LCDGameModes which will allow LCDGameModes to determine whether it is able to use a 25.175MHz based screen mode or the original 24MHz based screen mode to exploit the available hardware and achieve the best possible screen display for gaming on any given hardware


AutoVIDC 2.10 has undergone the most rigorous and extensive testing of any AutoVIDC module to date. With over 40,000 RMLoad/RMKill cycles and over 750,000 SWI calls performed during the testing process to ensure maximum stability whilst in operation.

Download now!

The AutoVIDC v2.10 software is available as a free download with full source code from the AutoVIDC page

Posted on: 11 Jun 2013@20:31:12, updated on: 11 Jun 2013@20:31:12.


LCDGameModes enters public beta - download today!

LCDGameModes a module that runs on RISC OS 3.xx and is able to patch many games for the Archimedes range of computers so that they will play correctly on a (S)VGA capable monitor such as modern TFT flat screens as shown in the photo below.

Zarch running on a TFT flat screen monitor with the correct aspect ratio

LCDGameModes is able to fix many games that will not normally display correctly on VGA monitors and it also fixes the aspect ratio of many games so that they are displayed more accurately and appear as they would when played on a traditional 15kHz TV style monitor.

For more information and to download the first public beta release of LCDGameModes visit the LCDGameModes page.

Posted on: 13 May 2013@00:22:10, updated on: 13 May 2013@00:22:10.


AutoVIDC v2.07 supports WE Super VIDC Enhancers!

With the release of AutoVIDC v2.07 for the first time ever, there is a single standard API that provides control over the setting of the Archimedes' VIDC1a clock speed regardless of the type of clock selection circuitry fitted to the machine.

A Watford Electronics VIDC Enhancer

With the addition of support for VIDC Enhancers made by Watford Electronics, the AutoVIDC module now supports the following VIDC clock selection devices:

By supporting the various VIDC clock selection technologies, users can dispense with the need for proprietary software to create and control screen mode definitions which need to be "Enhancer aware".

Instead, AutoVIDC supports custom screen modes that do not require built in clock selection routines and it can automatically switch to the correct clock speed based on the mode definition itself. This method of detecting and switching to the required VIDC clock speed delivers a consistent Acorn-like user experience across all Acorn VIDC1a based machines.

You can find out more about AutoVIDC, Retro-Kit Ultra VIDC Enhancers and Watford Electronics VIDC Enhancers by following their links.

Posted on: 25 Apr 2013@01:05:19, updated on: 25 Apr 2013@01:05:19.


When UPURS meets Serial Tube, UPURSFS is born!

Using UPURS by Martin Barr to quickly transfer disc images to and from the BBC Micro over a fast serial link has been a reality for a year or more. It has proved to be a reliable and cost effective way to archive DFS discs and transfer disc images back to the BBC Micro when required.

For several months now, Stephen Harris has been working on developing a version of J.G. Harston's HostFS ROM which uses the UPURS serial link to provide a fast remote file system using a Windows or Linux PC as a file server. This week saw the first release of Stephens work UPURSFS which you can see running in the photo below.

UPURSFS ROM displaying the banner after power on

The file system supports all the features of a BBC Micro based filesystem that you would expect and provides access to the PC's hard drive.

You can find out more about UPURSFS on my UPURS webpage.

Posted on: 18 Apr 2013@23:55:38, updated on: 18 Apr 2013@23:55:38.


Repairing a RAM control line failure on an A5000

Last month my A5000 failed whilst on soak test for a separate repair. The failure this time was a RAM control line failure which resulted in a dead A5000. In the photo below you can see the discolouration of the pads and legs on the 74AC138 which overheated and burnt out.

A5000 RAM control circuitry after overheating

You can read about how I repaired this fault and restored the A5000 to full operation on the A5000 RAM control line repair page.

Posted on: 10 Apr 2013@23:44:48, updated on: 10 Apr 2013@23:44:48.


AutoVIDC v2.05 and CustomVDU v1.71 released

Download AutoVIDC v2.05 and Custom VDU v1.71Today sees the release of AutoVIDC v2.05 and CustomVDU v1.71.

AutoVIDC v2.05 contains a minor bug fix which addresses a problem when using the module with later Acorn machines based on the VIDC1a Video Processor chip that do not need a VIDC Enhancer.

In this case, previous versions of the module were incorrectly setting the Sync.Polarity for some modes which caused screens to be offset slightly or incorrectly letterboxed on occasion.

The module also now contains a new SWI which returns the correct Sync. Polarity configuration for any given MODE and MonitorType values passed in.

I'm also pleased to announce an official update and release of Thomas Olsson's CustomVDU application which is a complimentary release to AutoVIDC.

The updates to CustomVDU, alter the way in which a custom mode's base mode is derived and provides a way for both !CustomVDU and AutoVIDC to determine the correct Sync. Polarity for any custom modes created using the correct base mode definition.

I'd like to thank Thomas Olsson of Armware for providing me with an uncrunched copy of the !CustomVDU source code and for then packaging up my changes to the source into an official release.

AutoVIDC v2.05 and CustomVDU v1.71 are both available for download from the Retro-Kit UltraVIDC Enhancer page.

Posted on: 22 Mar 2013@17:14:31, updated on: 22 Mar 2013@17:14:31.


Control-IT buffer box software rediscovered!

In January 2013, BBC Micro versions of software for the Control-IT buffer box was rediscovered and archived for the future and it's now available for download from my site.

Deltronics Control-IT buffer box

The download consists of two floppy disc images called Control-IT and Contact. The Control-IT disc contains utilities and basic tools to control the buffer box and Contact contains the full programming language of the same name which allows a user to create interactive programs which react to input and can control devices through the buffer box.

You can download the software from the Deltronics Control-IT page here

Posted on: 21 Mar 2013@02:08:50, updated on: 21 Mar 2013@02:08:50.


Using the Retro-Kit collection for education

For the last few weeks, I've been running a Code Club at one of the local primary schools here in the East Midlands. To give the Code Club something extra, I've been using some of the computers in my collection to demonstrate to the children and help them to discover the history of british computing.

On Monday the 4th of March, BBC Radio Leicester attended one of the Code Clubs that I lead and interviewed the children, teachers and myself about the club, what we do and how it works.

The interviews were aired on Jonathan Lampon's Breakfast Show and can be listened to using the BBC iPlayer for seven days from the original air date. The piece starts at 2 hours and 40 minutes into the show.

You can also read more about using my collection in the Code Club here.

Posted on: 7 Mar 2013@21:41:41, updated on: 7 Mar 2013@21:41:41.


AutoVIDC v2.04 now available for download

Download AutoVIDC v2.04AutoVIDC v2.04, the software that controls the Retro-Kit and other compatible VIDC Enhancers is now available for immediate download.

This latest version of AutoVIDC represents a huge step forward in automatically managing VIDC Enhancers and also improves compatibility with different versions of RISC OS.

What's new in AutoVIDC v2.04

  • Re-factored to compile using the ARM Assembler, ExtASM 2
  • RISC OS support has been improved
  • 26/32-bit architecture neutral
  • Adds several SWI functions for programmers to manage the VIDC clock speed
  • Improved support for custom modes created by games under RISC OS 3
  • Supports 1, 2 or 3 additional VIDC clock speeds in addition to the native VIDC clock
  • Allows for extensive control of VIDC Enhancers for the purposes of over-clocking using an Ultra VIDC Enhancer
  • Increased stability through interrupt management

Features in depth

Re-factored source code

AutoVIDC v2.04 has been re-factored to compile using the ARM Assembler, ExtASM 2. The purpose of re-factoring was to address the shortcomings of the Acorn BASIC ARM Assembler and make the source code more maintainable. Whilst doing this, it made sense to re-build the code in a 26/32-bit neutral way.

Increased hardware support

Re-building AutoVIDC also presented the opportunity to test the module on many more hardware platforms than was previously possible and it has now been tested on an Archimedes A310, A410/1, Acorn BBC A3000, Archimedes A540, Acorn A5000 and an Acorn A4000. These machines were running a variety of versions of RISC OS from RISC OS 2 through to RISC OS 3.11. In fact, AutoVIDC v2.04 is the very first version of AutoVIDC to fully support RISC OS 2.

In further platform testing, AutoVIDCv2.04 also behaves appropriately on the Acorn RISC PC and, as a benefit of being 26/32-bit neutral it has also been tested on the Raspberry Pi running RISC OS 5 to ensure that it behaves correctly on as many hardware platforms as possible.

Supported hardware has been widened so that it now supports any Acorn computer fitted with a VIDC1(a) video controller regardless of whether it requires a VIDC Enhancer or not. The reason for this increased support is so that AutoVIDC can provide a set of SWI's (Software Interrupts) which for the first time delivers a standard API for the control of the VIDC clock speed across all VIDC1(a) based Acorn computers.

Improved support for game modes

AutoVIDC v2.04 is now much more aware of which version of RISC OS it is running on. When RISC OS 3 is detected for instance, it uses several techniques to improve support for custom modes which are created by desktop applications such as !CustomVDU or video games that use custom displays.

Where a game dynamically creates a custom mode, previously, the user has had to almost guess which modes would need to be enhanced prior to launching the game. When AutoVIDC detects a mode change, if the mode isn't specifically set as requiring a VIDC Enhancer using the traditional mode map lists, it can now detect which clock speed is required and control the VIDC Enhancer to deliver the required VIDC clock speed automatically.

Increased support of VIDC Enhancers

AutoVIDC v2.04 now supports VIDC Enhancers with one, two or three additional clock speeds and gives over-clocker's the ultimate flexibility in controlling the VIDC clock delivering all the standard VIDC clock speeds plus an extra clock speed dedicated to over-clocking the VIDC chip when used with an Ultra VIDC Enhancer. It does all of this without sacrificing any support for any VIDC Enhancer that is controlled via the Archimedes' Aux I/O header.

Improved stability

AutoVIDC v2.04 has been extensively tested thoroughly and introduces many features which work to improve the stability of the module. For instance, AutoVIDC v2.04 disables all interrupts whilst it accesses hardware latches in the memory map whereas all previous versions of AutoVIDC do not. 

Download AutoVIDC v2.04

AutoVIDC v2.04 is available for immediate download (and includes all source code) from this site as both an 800KB adf disc image and a stand-alone zip file.

Posted on: 1 Mar 2013@02:05:03, updated on: 1 Mar 2013@02:05:03.


Hybrid Music System - Sounds of the 80's

Over the last few months, I've been building up a Hybrid Music System as part of the Retro-Kit collection. A few weeks ago, I was contacted by someone who asked if I could help them recover some of their musical arrangements that were written in AMPLE created using the Hybrid Music System in the late 80's and early 90's. This gave me the perfect opportunity to build up the system and complete my Hybrid Music System pages.

The Hybrid Music System

My Hybrid Music System is missing the Music 2000 MIDI interface and Music 3000 Expander but it does feature the rare Hybrid 6000 Sensor which uses a 50kHz sound beam to detect the users distance from the sensor and play notes on the musical scale accordingly.

Posted on: 28 Feb 2013@00:09:26, updated on: 28 Feb 2013@00:09:26.


Announcing the new Ultra VIDC Enhancer

After the relative success of my first foray into hardware development using an adapted version of Andreas Barth's VIDC Enhancer design, I was keen to have a look at seeing if I could improve on the original. There were no bugs to speak of, just a nagging feeling that I could do better!

With that in mind, over the 2012 Christmas period, I took the time to flesh out my ideas about how I'd re-develop the VIDC Enhancer and set about creating an entirely new design that met all of my requirements which were:

  • Allow more than one oscillator to be fitted on a single board
  • Allow for over-clocking to achieve higher screen resolutions if desired
  • Retain the Sync on Green fix from the previous design
  • Work in all the Archimedes models that need it
  • Be small and low profile
  • Use as little signal processing as possible
  • The installation process must be reversible
To meet those requirements, I researched several logic chips to see if all of the functions that I required existed in a single chip. I found the 74ACT153; this chip has the facility to take a 2-bit signal and use it to choose between four input signals and output just one of them at a time. Perfect. Having chosen the chip, I set about making up a design on a breadboard to test.

An Ultra VIDC Enhancer running on a breadboard

The breadboard version didn't have a Sync on Green fix in place but produced a perfectly acceptable display (apart from it being Purple) and you can see that in the photo below.

The bread board VIDC Enhancer without Sync on Green in use

Having successfully built a multi-oscillator VIDC Enhancer design, I created the schematic and designed the PCB layout and sent the drawings away to be manufactured. 

The Ultra VIDC Enhancer PCB layout

The design features a double sided full copper pour ground plane to reduce signal interference and provides space for three extra oscillators and it measures just 51x36mm.

Twelve days later, the boards came back looking like this and ready for construction.

The Ultra VIDC Enhancer PCB

After building a board up for my Archimedes A310, I installed and tested it and it worked perfectly with the added bonus of it allowing you to over-clock the VIDC chip if you want to without having to change the existing oscillators.

The Ultra VIDC Enhancer fitted to my Archimedes A310

The display output is excellent with little to no discernible interference on screen delivering a nice sharp image with even colours. 

Archimedes A310 running RISC OS 3.10 in MODE 31 using an Ultra VIDC Enhancer

I've now completed a new installation manualdriver software and software manual for the Ultra VIDC Enhancer and there are now a limited number of Ultra VIDC Enhancers available to buy so you can upgrade your old Archimedes today.

Posted on: 1 Feb 2013@18:04:47, updated on: 1 Feb 2013@18:04:47.


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Pre-order your Ultra VIDC Enhancer now

I opened up a list of pre-orders in anticipation of creating a new batch of Ultra VIDC Enhancers in 2016. Due to delays, they're now going to be ready in July 2020. Please contact me to enquire about being placed on a pre-order list. No payment is necessary until the Ultra VIDC Enhancers are ready to ship.

A3000 Ultra VIDC kit

The anticipated price should remain the same at £32.50 each + £6.95 P&P to locations in the UK (other countries may incur greater shipping costs). The package includes the Ultra VIDC Enhancer, all connecting cables, headers and jumpers required for your Archimedes and a 3.5" floppy disc with the software on.

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