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I'm going to make them available when I have it in a case. I think I have the cassette saving/loading and main case to design left to do.

Raccoon so, especially the most recent faster revision.

@@DevelopIT already found someone running doom.

For anyone else looking at this in the future. Bit 7 is horizontal flip, Bit 6 is vertical flip, and the remaining 6 bits need to be shifted up by two for the tileId. Working backwards, if the game code wants to display a sprite with tileIndex of 72 that is flipped both vertical and horizontally then the tileId would be calculated like this: (72 >> 2) | (1 << 7) | (1 << 6), which gives a tileId of 210.

Sorry for the delay, I should hopefully be doing another video soon, had to spend some time fixing my car and catching up on other stuff I let slip.

@@DevelopIT no worries at all mate, life always gets in the way of this stuff. It gave me time to work it out for myself and i have it all working for Namco Set 2. Spent a little bit of time today trying to get it working for Set 1, but had to leave it to deal with family stuff. My current plan is to get Set 1 done and then move on to Scramble. Looking forward to another video!

There are USB and Bluetooth ELM327 devices which can be found on eBay. They plug into the OBDII connector on the vehicle.

I've done Amidar and Time Pilot and they both use methods used previously for tiles and sprites, Time Pilot is a great game. I try and keep the videos short and go in depth into one or two items per video, next video I do I'll look at tiles in more depth. Moon Cresta was a challenge for graphic ROM selection.

@@DevelopIT looking forward to your next video. I don’t think I have ever played Time Pilot, will have to fire up RetroArch and have a game. Always been a fan of Moon Cresta though.

If you programmed your synthesiser using Objective C, that is very impressive, I could never get my head around that language. A synthesiser is impressive in itself, not a simple task. My target is to get as many emulators running on a Raspberry Pi Pico as I can with a keyboard so retro computers and arcade machines can be used on a VGA monitor with keyboard. As all projects it tends to be cascading quite a bit.

@@DevelopIT i did it in Swift, but Objective-C used to be my favourite language. I hated it the first time i used it, however it really grew on me and i came to love it. Once Swift was introduced i never looked back. I am an iOS App Developer by trade, started out as C programmer in the early 90s. Your project sounds awesome, my side projects tend to never get finished, usually i go back to them after a year or so though. I have been building an arcade machine for 8 years 😂

@@ConfusedNDazed I made a Mame upright over a decade ago, the joystick has been broken for years, so many things in the queue to get done. Hope your project goes well.

Moon Cresta is on my list to do, I'll check it out next. When I did Frogger, the schematic had a part labelled Star Field and the rest of the circuit looked very similar to Galaxian, I was thinking there may be versions of the Galxian ROM set that would run on Frogger, but the ROMs I have wouldn't. I hope Moon Cresta does, it would save me a lot of time.

The alternate scheme was just having dark grey ghosts returning once eaten rather then just eyes, and filled walls. Ms PacMan should just work, the only difference I found between ROM sets is that some use Z80 interrupt mode 1 and some use mode 2. I have done Crazy Kong and Frogger, just need to do videos. Next I may try Berzerk.

@@DevelopIT oh I didn’t even try Ms PacMan in my emulator, just assumed it wouldn’t work out of the box. I’ll implement mode 1 interrupts in my CPU and give it a go. I’ve never played Crazy Kong before, will have to have a look. Just saw another one of your videos pop up in my feed, will watch it now.

LOL

I didn't realise that, BBC Micros were what we had at school. It's an amazing chip considering it does almost as much as the AY audio chips.

@@DevelopIT Yes. Up until recently I thought it was an AY based chip inside them. As you probably know the AY chips ruled the computer and arcade game sound world until the Yamaha YM range with FM synthesis took over.

The Star Field, is just a random number generator, I started doing what I think the circuit is doing, but I ended up doing something that I think looks right. I hope the PacMan one goes well for you. I have just completed PacMan, without the audio. It has a complexity the way it uses interrupts. Some ROMs use interrupt mode 2 and some use interrupt mode 1.

@@DevelopIT You’ve just completed PacMan?? You’re on fire! Ive been doing it for 3 months and just got the Test Screen displaying up until the grid (then it loops). That time included writing the Z80 CPU though. Oh some use mode1? I only implemented mode 2 so far. Am pretty happy with my progress, hopefully i have it displaying the attract screen by the end of today (Aus time) Are you going to do a video on PacMan? What is your next game you are going to tackle?

@@ConfusedNDazed It took me a number of months to get the Z80 emulation done too. Hopefully I'll get a video about PacMan done next week at some point. I started Missile Command after PacMan, the display is a bit complex so I put it aside for now and did Crazy Kong instead, which is pretty much there now.

I talk though the source code at the end of the video, but the source code is not OpenSource.

I think it depends on the quality of the super capacitors. I have some small 10F capacitors that stay charged for weeks. I don't remember about these 500F ones, but they do loose charge faster.

@@DevelopIT 500f?

It's the way it always goes, when I start a project, I too always end up with more projects on the list by the end.

I have done a Galaxians emulation now and when I get time to do a video, I'll go in depth. It is a more interesting emulation as the Galaxians has hardware sprites as well as tiles.

@@DevelopIT Will that be a tutorial where you explain step-by-step how to code the emulator or a review of the code ?

@@benjamindeharo314 Just posted a video last night about Galaxians PCB, with more in depth explanation on how to go about emulating an Arcade PCB.

@@DevelopIT thank you, I'm going to watch it right now

With the Z80 I start off putting the ROM that looks like it executes first at the bottom of memory then evolve from there. My Z80 emulator shows what memory and IO ports have been accessed. Can usually see bitmapped display memory & character maps. I get it as far as I can, if I get stuck on something I try and work it out from the circuit diagram or do a search to see if the info is available. I may do a video on how I go about a new emulator. It's worth while doing as I'm sure you appreciate it's a great learning experience.

Thanks for the explanation. If you make that video, I would definitely watch it!

@@ConfusedNDazed I've just done a Galaxians PCB emulation. When I get time to do a video, I'll go into much more depth.

@@DevelopIT don’t tease me like that!!! Can’t wait to see it mate.

@@ConfusedNDazed Just posed the emulating Galaxians video last night.

A while ago I thought I would pick up some monitors cheap from eBay. Because businesses have to pay to scrap things like this I got about 10 of them for £20. They are small and tidy, I like them.

Thank you for the feedback. derramp5113 is still producing great videos, I always watch his content.

Thank you.

Thanks. It's been a while since I worked on this project. BTW you don't need to assemble a CP/M - CCP and BDOS, I just lifted the ones I use from the boot tracks of an Altair 8800 disk image. They need to load into memory at the place they where originally intended and your BIOS just sits above them in memory.

​@@DevelopIT Thanks for the tip! That makes sense. I've put a simple memory paging circuit into my board - 512K of Flash and 512K of RAM are sliced into 32K pages and can be freely arranged into upper/lower 32K of Z80's address space. The cold reset configuration puts the zero page Flash on lower 32K and zero page RAM into upper 32K, so it will be possible for a bootloader routine to place the required images where the CP/M expects them. Once you've gotten the CP/M running - aside from playing Zork, what did you experiment with on your machine?

@@MichalKobuszewski I didn't go any more then 64K myself, you should be able to do some multi-media things that I wont be able to do. For me ultimately I want to sell off all my retro systems and just run some of my own creations and do a bunch of development.

That must have been a great environment to work in. I started work and college a bit later in 86. That was the best time when people where more relaxed and were more dedicated to their work as it was a more enjoyable environment.

Only as far as it can reset the OBDII error codes.

It may be that the filament is broken in the PVC tube and causing an issue. Or the friction that is trying to drive the filament is not pushing the filament, also carefully check the hot end is heating. The issues I have seen is usually when it detects the filament is not moving. The hot end may need disassembling and cleaning.

The linear voltage regulator will use additional power to regulate the voltage, even when in sleep mode, and shorten the battery life of a charged battery. The concept of the video is to get maximum life from low power applications.

@@DevelopIT i see. thanks for the information.

I didn't realise the Spectrum + case was available as an upgrade. I had always thought you had to buy and complete Spectrum + if you wanted the + case. I always preferred the original myself.

As far as I remember it's just using Python libraries and I don't think any are specific to Raspberry Pi. I haven't tried it but it may well work on any Linux with Python.

Unfortunately for this project I don't think I will. As ultimately I will need to start making money from a product and this may be part of it. I will still open source other source code occasionally.

I don't know if that is possible. It would be a harsh environment and the materials may not be appropriate.

I agree, micro controllers are so versatile these days and the RP2040 at £1 each makes most discrete electronics redundant. I still like to experiment at component level. Your comment made me think, just like modern computers remove users from the concept of programming, modern micro controllers will probably create a generation of people who may not appreciate component level electronics as much.

Thank you, I appreciate the feedback.

The commands are listed in the README.TXT file of the GitHub project here: github.com/BirchJD/PiOBDII/

@@DevelopIT My bluetooth dongle constantly connects, then disconnects. Do you think it's a compatibility problem?

@@SpaceAgePac I couldn't say, I've had that issue with pairing my phone to a particular device in the past, so it may be.

Thank you. Every project always becomes much more than originally intended, it's a never ending story.

They are at the end of the video. At some point I will make a schematics area in my GitHub and put schematics like this there.

I think you should be able to. That is effectively what this circuit does, but also generates the higher voltage. So you would need to level shift to the RS232 voltage levels.

I'm the same, I use the heat transfer paper method as I find it easier. Though most of the PCBs I want currently are a bit too complex to make at home easily.

Write it on a piece of paper, place it under your pillow at night, maybe in the morning you shall have a surprise.