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Defence Force

@DefenceForceOrg

Game Developer (Adeline, Heliovision, Eden, Funcom), Retro Enthusiast (Oric, Atari, Audio), YouTuber (youtube.com/c/Dbugsstuff)

Norwaydefence-force.orgJoined September 2014

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Defence Force

@DefenceForceOrg

Oct 8, 2022

Since recently a bunch of people started to follow me (thanks by the way!), maybe it's time to give some useful information about what I'm doing. 😅 I'm working in video games (mobygames.com/developer/shee) currently a Tool programmer at

@Funcom

. ⤵️

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Defence Force

@DefenceForceOrg

I'm wondering... should I keep the name on Twitter "Defence Force", or switch to "Dbug" or even to my actual real name? Originally I made the account to indicate the downtimes, maintenance and updates of defence-force.org, but we are far past that point now. 😅

When you make a selection it cannot be changed

Keep "Defence Force"

Use "Dbug" (my nickname)

Use "Mickaël Pointier"

Other (add comment!)

24 votes2 days left

Defence Force

@DefenceForceOrg

21h

Not every day I see people playing my 20 years old Donkey Kong for the Oric 😅

youtube.com

4K Kong by Defence Force - Oric Atmos - Actual Hardware - 323 points.

Trying out the Maxduino player with 4K Kong, a tribute to the old Game and Watch games from the eighties. Written by Michael Pointier (Dbug), it was released...

Defence Force

@DefenceForceOrg

Feb 4

Since I was not able to find a pinout for the 36 edge connector, I used a combination of scope and contact check to find more of the pins. Some feels so random, like why are the difficulty switches for the left and right players and "speed" grounded, but "serve" uses two pins🤔

Defence Force

@DefenceForceOrg

Feb 4

If you want to avoid killing more trees, you can get the scans of all these books for free in the Oric library (like that one library.defence-force.org/index.php?cont ) in a searchable and copiable PDF format which is much more practical than typing in BASIC source code from a paper book.

I'm glad to see that all the work done to scan Oric books and magazines to make them available to everybody publicly is actually useful. I just wish they were showing at least some examples of what their reprints look like, and somewhat mentioned the source.

Top searches on Google that end up on my blog. Out of the top ten, four are about croissants. 🤔 #seo #fail

Defence Force

@DefenceForceOrg

Jan 31

I watched an upgrade video yesterday by

@MarkFixesStuff

where the audio circuitry of the Sinclair/Amstrad ZX Spectrum+3 is modified to fix sound issues. Generally improvements are modest, but here it's quite a change. Can hear at the bottom of that page:

spectrumforeveryone.com

Fixing Audio Distortion on the Spectrum +3 - Spectrum for Everyone

Share the post "Fixing Audio Distortion on the Spectrum +3" FacebookGoogle+TwitterEmailBookmark The Spectrum +3 (Z70830 PCB) was the first fully[...]

Defence Force

@DefenceForceOrg

Jan 30

That explains the somewhat convoluted logic on the boards: To detect that the user pressed "1" by testing for a contact between the violet 🟣and green 🟢 lines, while green and gray would be "2" and green and orange would be "3". This reduces the number of required contacts.👍

The RESET button works as expected: It does a contact between ground and some pin. 😅 All the other works in combination, which means they are not designed to handle multiple buttons being pressed at the same time: You either press 1 or 5, but not both at the same time. ⤵️

I was wondering how the game select buttons were handled, it did not look like from the cartridge side there was a clear logic on why they would use a specific button for a specific game, but I guess that makes sense considering how they did it. ⤵️

Today I traced another game, which was using only half as many connections on the bus, easier to check if I got anything wrong. Let say I want to try to build my own card, what would be the easiest way to have such a double sided cartridge connector attached to a breadboard?

Defence Force

@DefenceForceOrg

Jan 29

I opened the second light gun (the one which had a complete wire), and interestingly the trigger mechanism is different (uses a proper micro-switch), and the PCB is identical... except that one has actual components (a CD4011BCN / Quad 2-Input NAND) instead of holes 🤔

Defence Force

@DefenceForceOrg

Jan 29

This is possibly related to the presence of "Bat Position Adjustment" knows on the Super Sportif cartridge... but then, why don't the later games have any of these drift compensation knobs?🤔 Feel free to provide ideas, there are no stupid suggestions as far as I'm concerned 😇

The analog joysticks on this console are using a pretty neat system, it's still working flawlessly after more than 40 years. What I'm wondering is why would you use a 100 k ohms resistance on the vertical axis and a 50 k ohms resistance on the horizontal axis. 🤔 ⤵️

Always nice to get new colorful Oric games :)

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oric.iss

@oric_iss

Jan 27

In honor of the #Oric's official 40th birthday we release our remake of the classic game #PUTUP (demo)! Download: forum.defence-force.org/viewtopic.php?

Defence Force

@DefenceForceOrg

Jan 28

Tracing even simple circuit boards is not particularly trivial when you take into account the messy solder blobs, non insulated bodge wires, glued over components, and tracks that pass under large components.🤔 I've too many "Ball Speed Inhibit" connections, so done for today 😅

10 years ago,

published this article about the 30 years anniversary of the #Oric 1. So I guess that means it's celebrating its 40 years 😇 theregister.com/2013/01/28/the Happy birthday!

Defence Force

@DefenceForceOrg

Jan 28

If there is any #oric owner with a working Microdisc, Jasmin or Cumana 3" drive around Manchester, maybe you can help?

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Kevin Edwards ( Retro Videogame development )

@KevEdwardsRetro

Jan 27

Does anyone have a 3" disk drive I could buy/borrow - preferably in UK/near Manchester? I seem to have lost mine and I have some archiving I need to do. Just to clarify I'm after a 3" drive as used by Amstrad CPC6128 / PCW and Spectrum +3, not the common 3.5" ones in PCs/Amiga/ST

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Defence Force

@DefenceForceOrg

Jan 26

Basically it means you need to keep a list of redirects, that you never rename pictures or pages, that you keep the same technological stack so old links still resolve to something valid, even when they use parameters on the url, etc... this is not trivial at all. 🤔

I guess anyone who has to use StackOverflow and find an answer of 5 or 10 years ago already know that most of the links in the answers are pointing to things that have vanished. I've tried to keep working links for Defence-Force.org these last 25 years, and it's hard! ⤵️

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Robyn Caplan

@robyncaplan

Jan 25

Whoever claimed that the "internet is forever" didn't have to go back to the internet of 2009 for a research project only to find that 75% of the links go nowhere now.

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Defence Force

@DefenceForceOrg

Jan 24

And if you wondered about the cartridge, here it is. Compared to some other cartridges, it looks like that one was assembled by a master jeweler. 😅

The final "cheat" is to use some label paper to reinforce a bit the box. It's not particularly pretty, but at least now the box can close, and actually keeps a proper shape, so the manual and the cartridge can be stored in it. ⤵️

Next day, the box is all flat, and is almost A4 sized, and the manual almost looks good. ⤵️

Second step, flatten the cardboard into submission by spraying some water on the back side and sandwiching it between two bits of cardboard, then use the power of books to let it rest during the night. Same method for the manual ⤵️

Today's next step was trying to fix the packaging for the game cartridges. First step, open the box and remove the stickers (using a thin blade and a hair dryer) ⤵️

Thing is about 44 years old, so all things considered it's quite in a good shape, all the parts are there, all I need is to find the pinout and remake a cable for it. Just a thorough clean-up, and then time to assembled it again :) #RETROGAMING #pong #duckhunt

The trigger system is actually greased, and is made of a trigger, a spring to provide a good tension and an actual contact made of two bands of copper ⤵️

The optical module is on the tube on the top, and in the front is a red plastic lens. ⤵️

Just three screws, and you can access the inside. I was expecting a light sensor, but not an actual PCB with components on it. I've to admit that I'm perplex regarding the many unused holes. ⤵️

A common issue with these old Pong games, is that everybody has the "Shooting Gallery" but without the gun. I found one which was used by kids, but they cut the wire, so I'll need to rewire it, but since it's super dirty, time to clean-up and look inside. ⤵️

Forgot to mention the executable and source code is available on the feedback thread: forum.defence-force.org/viewtopic.php?

Here is the first release of the TapeRipper software, it will probably fail on a lot of things, but that's the first proper release and it did work with DBUG at least, so that's not a totally wasted weekend 🥳

youtube.com

TapeRipper 2.0 - Proof of concept / Request for feedback

A long time ago, I wrote a quick and dirty program to copy software from a tape onto a floppy disk to avoid having to deal with sampling audio and then tryin...

The main issue, is that most tape software did not really care about some important locations in memory, like the page 4 (which contains important DOS thing), or your own ripper program, so I had to relocate. But it's working, I've a DSK with the file now. 😅

Fortunately, Symoon wrote some routines to call Sedoric from assembler (can find that in CEO-MAG issue 153), so I reworked the program to automatically load from tape and save to disk without human help. ⤵️

My original ripper was kind of lame: Because I did not know how to call SEDORIC functions from a C or assembler program, instead I printed the command to the screen, so the user would run it from the interactive shell. That often worked, but in some case would get corrupted.⤵️

No I just need to find my ripper/saver, which loads a program block by block without running it, and save that as Sedoric files on the Cumulus, then load that on the PC, but I guess that will be for tomorrow :)

The UI is a bit rough, all the commands are two characters long, HR switches to HIRES, TX switches back to TEXT, MO brings back the monitor, DP displays the memory, HP shows the list of the commands.

The tape even loads without any problem.

I scanned all the documents and added proper credits and date on oric.org, also fixed the name from D-bug to DBUG (because it's what it is called on the manual). I'll try to dump the content if it's not yet available. oric.org/index.php?page

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