Worklog Mylar (working title) - An Ashida inspired, knock-off Tanto, Dreamcast Portable

[Teatimetim]

I've already poured many hours into this project so I figured it is time to start a worklog to keep track of my progress! My original hope was to submit this as part of the 2024 Summer Contest, but my procrastination got in the way and I failed to register before the cutoff date. Anyhow... I'm continuing forward with this project as a challenge for myself to learn new tools/skills. With that, I introduce to you all....

Mylar

I am in no way an expert in Fusion 360, so it took me forever to get to this point. I watched a ton of videos on how to model controllers in Fusion 360 which was my starting point for this project:

Using the Dreamcast Controller 3d scans by Wesk, I managed to freeform a shape using the scans as a reference. It's not perfect by any means, but I felt like it was good enough to continue forward.

After a lot of tedious work, failures, redos, crying, and swearing.... I got the controller shelled and button holes cut out.

Next up was checking for fitment to ensure I could make some custom PCBs fit with the buttons and OEM trigger assemblies:

Success! After a few iterations and prints I managed to get the assembly feeling pretty good so I felt confident in creating the PCBs for the controllers:

The plan is to use the hall effect TMR PS5 joystick along with the Hall effect trigger assemblies from an OEM Dreamcast controller. I will also be using Yveltalgriffin's MaplePad to handle the VMU emulation and controller settings (https://github.com/mackieks/MaplePad)

 

[Teatimetim]

I also ran a test print of the front half of the shell just to see how it would work out, and I'm happy to report that not only does it fit on a Bambulabs P1S plate, the structure seemed to hold up well!

There is still a lot of work to do to create the mounting points, shadow lines, etc.... but baby steps!

I almost forgot to mention the PMS! I'm using a modified version of Gman's PMS that produces the necessary voltages for a Dreamcast.

The 1v rail was removed and the 1v8 and 1v15 rails were replaced with 2v5 and 2v. The rest remained the same. I don't have any good pictures of it wired up to the Dreamcast and working, so you'll just have to trust me when I say it works.

Yveltalgriffin also graciously opensourced his flex for the gdemu for soldering an ffc, and I created an alternate flex to be soldered to the Dreamcast:

Unfortunately I haven't been able to get this to work yet, so I'll need to do more troubleshooting. For the time being I wired all 50 pads....

 

[Stitches]

That's some fine modelling you've done there. Very nice!

 

[Wesk]

Tanto is vaporware, so I think yours is now the legit original.

 

[Fly_5]

Hi, I love your project, I also started one but with the board cut out and working with an ide-Sata adapter for SSD hard disk.
I am now with the design of the case, if you need help with the plate do not hesitate to communicate it to me, greetings!

 

[Teatimetim]

Been spending a lot of time on the top half of the shell. More goodies/updates to come soon.

 

[cy]

The design of this is absolutely beautiful! I already wanna build one! Huge respect to you for doing this! The modeling work that goes into these projects is incredible!

 

[Teatimetim]

As I started to figure out where to place the speakers and how to exactly position the oled, I got an idea to build a "Main control board" that would contain all the circuitry for MaplePad as well as the audio.

It also allows for the flexibility of using the SSD1306 I2C OLED by jumping "JP1", otherwise it will use SSD1331 SPI OLED by default. FFC connectors are also used instead of wires to connect to the controller daughter boards. It's still possible to wire them by hand by using the test pads located next to the FFCs if desired. In future iterations I would like to integrate an FFC to marry the top half of the shell (from this board) to the bottom half, similar to the N64HHv2 FFC connector. Ideally this would allow connecting the audio and maple bus via FFC to make for a cleaner build.

Right (ABXY) control board with optional FFC connector

Left (Stick & D-Pad) control board with optional FFC connector

Both daughter boards have their FFC connectors mounted on the back of the board (same side the trigger assembly is installed on) to make it easy to access since the button side is screwed down onto the face plate. And just like the main control board, each one has it's own set of test pads for manual wiring if desired (or troubleshooting).

Now is a good time to mention the issues I encountered with the TMR stick. In my original design, pin 1 of the pot was connected to 3v3, pin 2 was SX or SY, and pin 3 was GND. With regular non-hall effect sticks, it doesn't matter if pin 1 or pin 3 is 3v3, it will just reverse the direction of the stick but with good calibration (shout out to MaplePad and Yveltal's awesome work on calibration!) this is easily fixed. However, hall-effect sensors contain active circuitry, and in this case, requires Pin 1 to be GND and Pin 3 to be 3V3. I had the reverse in my original design and it was causing MaplePad to not boot during tests. Here is a picture of the circuitry in the pot of a PS5 TMR Joystick.

After encountering that issue, rather than trying to bodge it in which would require a lot of trace cutting and isolating of the board, I just swapped the TMR stick out with a regular PS4 Joystick. I'm happy to report that the results were great!

(One other quick note, double check the pin out and wires of the DC controller cable! I was looking at it from the wrong connector type and ended up shorting 5v into GND on the pi which was also causing it to not work)

Calibrating was a breeze for both the triggers and the joystick. The new hall effect sensors I used for the triggers worked beautifully in Sega Rally 2, and the joystick and other controls (+ the Oled for the VMU) worked great in Code Veronica! If you're interested in using MaplePad, be sure to compare the games you want to play to the Compatibility List since some games do have issues (mainly WinCE games).

With that, I got the new boards I created ordered and finally have the top shell in a state where I think I can call it "good enough" for now, at least for my first iteration. It's time for me to move onto working on the bottom half of the shell which means more model cleanup, adding mounting holes, more brackets, etc. Still a lot of work ahead but I'm happy with the progress I made so far!

 

[Teatimetim]

The design of this is absolutely beautiful! I already wanna build one! Huge respect to you for doing this! The modeling work that goes into these projects is incredible!

Thanks! Like with your N64 design, once I get it into a mostly complete state, I will be releasing the files for anyone to use how they see fit!

 

[Mr Game & Cube]

View attachment 34843

Dat big boi

In all seriousness though that looks amazing, good work man!

 

[Providencial]

Amazing work!

I feel compelled to mention that this year there was an excellent release of a DC USB controller adapter with full game compatibility and seamless VMU emulation (automatically creating a VMU file on a USB stick for every game you load on GDEMU).

Could be very useful for handhelds, don't know if it's a bit late for your project...

USB4MAPLE

 

[Teatimetim]

Amazing work!

I feel compelled to mention that this year there was an excellent release of a DC USB controller adapter with full game compatibility and seamless VMU emulation (automatically creating a VMU file on a USB stick for every game you load on GDEMU).

Could be very useful for handhelds, don't know if it's a bit late for your project...

USB4MAPLE

That's really cool, thanks for sharing! I do plan on adding a way to connect it to the TV at some point so maybe using something like that with a dock would work for multiplayer.

 

[Teatimetim]

Well, I dun goofed with my main control board layout and accidentally swapped the left and right controls, resulting in this mess:

On a more positive note, the board along with the new FFC connectors work great!

If I want to use the main control board as-is, at least for a prototype, I'll need to swap the RT and LT pins for ADC in the MaplePad code for the pico. I may do that before ordering a new board just so I can confirm no further mistakes were made with the audio which I haven't tested yet. That means next up should be trimming and seeing how everything fits! I tried allowing for tolerances in my design but there will be more tweaking I need to do for sure.

Edit: Yveltalgriffin just let me know that I can actually swap the mapping for RT and LT in the MaplePad menu so there should be no need to do any modification, thanks Yveltal!