There was also another gaming-platform that grew on me. This platform was the Super Nintendo Entertainment System (SNES). Next to obvious titles like Super Mario World, Super Metroid and several other (action-packed) games I began to take a huge interest in Role Playing Games (RPG’s) and the SNES had lots of excellent gems; not only Zelda 😊

It’s still to this date that my friends (and me) look back with fond memories from this Golden retro 80’s and 90’s era. In addition to my personal affection for both game-genres (Point-and-Click adventures and RPG's) I always had one thing in the back of my mind when growing up: I was constantly busy with electronics and dreamed of building my own, portable handheld device to experience the same feeling on-the-go. But of course I didn’t have sufficient funds and/or the experience + technical means to follow through. These last few years however, also due to technological innovations and several personal electronics + printing projects, including multiple programming language studies (especially Linux and HDL) it is now possible for me to build my own portable (retro) handheld machine, composed of a 3D printed outer shell in combination with custom electronics (like a Core, consisting of a SoC, RAM, eMMC and PMIC module, combined with a battery pack, custom controls and a display). If you have the patience, a solid (business)plan and your mind set the realisation of this project could be feasible 😊 I also believe there is a commercial market for this: People of my age who want to relive their precious Point-and-Click adventuring and RPG childhood (a niche part of the retro gaming market, but a market with a very active community and dedicated following).

My goal is to turn this project: Playing Point-and-Click adventures (ScummVM) and Role Playing Games (SNES) on-the-go by means of a pocketable, professional-made, commercial product... A long, cherished dream of mine.

Next to a well chosen display for this device (more on this later) I also want to invest heavily in the design for the outer shell and the quality & placement of the controls. Ergonomics are very important, especially when dealing with these types of games, which tend to have longer play sessions than ‘normal’ games. The retro handheld market is a crowded market, especially during the last few years. Almost every two weeks there is a new handheld coming out from major companies like: Anbernic, Powkiddy, Ayaneo, Retroid Pocket, etc. As mentioned earlier I only want to corner a niche part of this market.

The first hurdle to take, when I thought of doing this project was the display. This is the first thing my target audience sees and interacts with. So, for me this must be spot on! It actually took some time to figure out the ideal resolution and/or model to use...

Classic Point-and-Click adventures were designed to be run at 320x200 pixels on a cathode-ray tube (CRT) television. During the 80’s and 90’s pixels were rectangular (instead of square pixels nowadays). This means that on modern systems these games look wider and fatter than they are supposed to. To correct this issue extra lines are added (pixel aspect ratio correction), which results in an overall image-resolution of 320x240 pixels @1X.

Maniac Mansion @3X 960x600 pixels Pixel Aspect-ratio Correction = Off	Maniac Mansion @3X 960x720 pixels Pixel Aspect-ratio Correction = On

Please notice 'The Moon' in the first picture, compared to 'The Moon' in the second picture. The Moon in the second picture is rounder and more natural looking. This could also be said for the faces/bodies of the characters (for an accurate comparison, please click on both images).

enlarge	enlarge	enlarge	enlarge	enlarge

Point-and-Click adventures, especially the early ones (see examples above) were well known for their pixel hunting ‘dilemma’ (finding small objects on the screen to interact with). These types of games were meant to be played on a big-sized television... When going for a smaller display (a handheld is a little smaller then a television 😉) there could be an issue regarding readability if the graphics aren’t top-notch. So the handheld display has to be as large as possible, but it has to remain pocketable. The up-scaled image (if applied) must also be pixel-perfect to distinguish these small hot-spots!

Many handheld companies use the option to up-scale the native resolution to fit the height of the display. This sounds like an excellent method, but actually there is a downsize to this method (especialy when you go pixel hunting). When the scaling factor is a non-integer (for example: 1.5x) the software is forced to use a scaling method like nearest-neighbor interpolation (this calculates the average colors of adjacent pixels of the image to scale). As a result, virtual objects on the screen are constantly changing in size, which could result in pixel shimmering, or jitter. A better scaling method is integer scaling, where every pixel is duplicated, which results in a clean, crisp image:
~ download the document ~

PICTURE 1: original sample image 4x1px PICTURE 2: nearest-neighbor interpolation scaling, 150% PICTURE 3: nearest-neighbor interpolation scaling, 190% PICTURE 4: integer scaling, 200%

There is a point of concern when doing integer scaling… If the upscaled-image doesn’t fit the display-height a black bar will be visible on top and on the bottom of the display. This is especially true if you are trying to emulate more than one gaming-system. And here lies the trade-off: Every gaming-system has its own native resolution. With integer scaling you have the best possible graphics at hand, but when black bars take up too much screen real estate your image won’t be readable (this is especially true for smaller displays). For this project, my focus in order of game-genre is: 1. Point-and-Click adventures >>> 2. Role Playing Games ... I need to have the Point-and-Click adventures at max. display-height, with 100% pixel accuracy (to distinguish the harder to ‘read’ pixels and/or hot-spots).

Integer scaling is an important tool. Ideally you want to use this scaling method for all your gaming-systems. I have made an Excel file that auto-calculates the black bars (in percentage) for different display resolutions.
~ click here to download ~

Another thing that turned out to be quite important, what limits my choice of available displays was the response-time... The Commodore scene (C64 & A500) was huge in Europe (even more so then in The United States). Major gaming companies were situated in European countries (read: PAL, 50Hz region). For SNES this was exactly the other way around. Major gaming companies were situated in Japan and The United States (read: NTSC, 60Hz region). Point-and-Click adventures, as well as RPG’s play at a relatively slow pace. However, cut-scenes (movie clips) and/or faster paced animations were also shown during play. NTSC operates @60Hz, this means a maximum of 60 frames per second. To find a handheld display that could actually hit the 60fps mark has proven harden than I initial thought... Every display has a certain value for its response-time (a measure of how quickly the pixels go from black to white and from white to black). SNES, the fastest targeted gaming-platform operates at max. 60 fps, which translates into a combined max. rise Time (Tr) and fall Time (Tf) of 16,67ms (1 second/60 frames per second). If the display is slower than this value, you could expect motion blur/ghosting when playing, which is an absolute no-go for me.

A couple of pages ago I mentioned: ‘It actually took some time to figure out the ideal resolution and/or model to use...’ It sure was a hunt, after searching for weeks (months even), contacting numerous companies all over the World and spending countless hours on the Internet/YouTube I concluded that my ideal display (see specs listed below) didn’t exist 😢

No company in the World is currently producing such a display, so until I can get Elon Musk onboard to team-up 😉 for paying the tooling cost to produce a new 4.7 inch 1280x960px AMOLED display (click here to download an in-game screenshot sample) I began to widen my search and started to make concessions between my ideal display and other displays that were available. A display of 4.5 inch @4:3 aspect-ratio translates into a screen-height of approx. 6,86 cm. I searched for a display substitute with more-or-less the same screen-height in cm (large enough to distinguish the hot-spots, but small enough to remain pocketable). I made a real-size comparison of these different displays, with an actual screen shot from the game ‘Indiana Jones and the Fate of Atlantis'.
~ click here to download ~

Black bars to the left and right are annoying, but this is certainly not a deal-breaker. For me the screen-height of the display is one of the most important factors regarding the readabilty of a certain game. There was a clear winner and actually it turned out that the chosen display was one of the most common of them all… Before I (finally) reveil my chosen display I should elaborate more on the different display-technologies... Basically, there are two display-types to choose from:

During my tests I found out that the response-time of more then 60% of the investigated LCD panels was higher than 20ms. This is, for me unacceptable. Next to that there were also issues regarding bad viewing angles, low contrast ratio’s, or high power consumptions. An investigated AMOLED display had a max. response-time of 2ms, excellent viewing angles, high contrast ratio and a low power consumption, which comes in handy in a handheld device 😉

The 5.55 inch, 1280x720 pixels, AMOLED display proofed to be my winner
~ download the specsheet ~

There was actually one more test I would like to share. Integer scaling is the prefereed scaling-method to choose, but when doing a head-to-head between integer scaling (pixel-perfect scaling) and nearest-neighbor interpolation (fit to display-height), the results somewhat suprised me during an actual game test of Zelda on the SNES platform.

enlarge	enlarge	enlarge	enlarge

Only a few of the many excellent SNES Role Playing Games... I ran a SNES test (see below) on an actual 1280x720px AMOLED (TT550RAN20A) display.

Both images were captured in their real size (not edited in any form).

The Legend of Zelda A link to the Past integer scaling @3X	The Legend of Zelda A link to the Past full screen @720p

Both movie clips were captured in their real size (not edited in any form).

~ download the clip ~ integer scaling @3X	~ download the clip ~ full screen @720p

I didn’t notice a slight quality-difference in the image capture, also the in-game animations run smoothly @both scaling options (with no pixel shimmering, or jitter). It could, however that for other games, or situations this will become an issue… So, my handheld project should give my target audience the option to switch between both scaling methods for the SNES platform.

This about concludes this section of the 'build'. I'm very happy with the chosen AMOLED display. Although I still believe a true 4:3 aspect-ratio display will offer a better nostalgic feeling, I think this is second best. The roadmap for this project is simple: After collecting the needed hardware, compiling and tweaking the software and finalizing my Proof of Concept (PoC) I’m planning to send out preliminary models to famous YouTube’ers of the scene (like ETA Prime, Retro Game Corps, Taki Udon, Micro Linux). At the same time, I will launch a crowdfunding campaign to professionally convert this idea into a commercial product, with 3 extra perks (goals):

enlarge

As for the heart of the system (the electronics) I am teaming up with Mangobuge, owner of MangoPi. This small company, based in Asia has a very dedicated and friendly designer, with an active community. It has already produced several (new) single Board Computers (SBC’s) with specs that out-perform its bigger brother, the Rapsberry Pi. Currently he is working on a new Core (a small footprint unit that contains a SoC + RAM + eMMC + PMIC module) that can handle all electronic tasks at hand.

I’m planning to use Linux as my main Operating System (OS).

For controls I’m going for a mix of elements from the classic (and still unbeatable, in my opinion) Nintendo Camecube Controller combined with the innovating trackpad design of the Steam Deck handheld. As mentioned earlier, I want this device to be pocketable. The screen size must be as large as possible, which is a problem (size-wise) when cramping in controls to the left and right. The solution is quite simple; a clamshell device. This will resemble (more-or-less) the iconic Nintendo Game Boy Advance SP, only with upgraded controls, display, and internal specs.

~ click here to return ~