Hand-held gaming mods : Success and FAILURE!

If failure is one of the basic freedoms, as the Fourth Doctor tells D84, a sentient robot in the Robots of Death, then I have had been feeling very free lately.

Lately I have had a resurgent interest, as regular readers of this blog may note, in the Game Boy line.  I had a Game Boy Pocket and finally decided to try to install a backlight into it.  I ordered my backlight from Hand Held Legend, and it came very quickly.  I wanted a white backlight so as to minimize the color change when the backlight is installed.  While it will not look exactly the same, the Pocket's screen is close to true grayscale.

Before I could add the backlight, I discovered that the A/C power socket was not providing power to the system.  Batteries would work, so I guessed it was a bad connection.  I did not have a multimeter handy which I could use as a continuity tester.  The only schematic I had was for a Game Boy Color, and while the power section is very similar, there are differences.  I was able to fix the issue by soldering a wire from the positive pin to the positive battery terminal.  I do not believe that socket is connected exactly in this way and I may have destroyed an Official Nintendo Game Boy Pocket AC Adapter getting it to work.  I believe that at the very least there is a diode between the positive pin and terminal.  Fortunately, I had bought a Radio Shack (Enercell) 3v/700W AC adapter that worked.  You need to get an Adaptaplug Type A and the tip must be positive.  Unfortunately the wire I used for the patch was a bit too thick at .22 or .24AWG to snake it comfortably around the case.  Most Game Boy cases are tight, and tighter than they look when it comes to mods.

Okay, I fixed the AC power socket so I could use my 64MB GB Smart Card.  With the AC attached, there are no issues with contrast fluctuations with the screen.  I have read that this is also a concern with the vastly superior EverDrive GB, one of which I hope to obtain by this Christmas.

Now came time to install the backlight.  To install a backlight in a Game Boy or Game Boy Pocket, you need to remove the reflective and polarizing layers from the glass Liquid Crystal Display.  In order to remove these two layers, you have to wedge a razor blade between the layers and the glass, get a corner separated and then carefully pull the layers from the glass without destroying the screen.  The screen has connections horizontally and vertically, and the layers are affixed to the screen with some kind of adhesive.

The hardest part of the mod is removing these layers without cracking the screen or irreparably damaging the connections between the screen and ribbon cable.  While the screen comes totally away from the PCB, the ribbon cable goes up the back where you need to pull.  You have to get your razor blade in there without slicing the ribbon and pull all the layer off without damaging the ribbon or dislodging the ribbons connections.  I thought I did it right, but after I removed the layers from the Game Boy Pocket's screen, I found I had damaged the connection between the screen and ribbon cable.  There was a large gap in the scrolling "Nintendo", at least 16 pixels wide.  Unfortunately, unlike with an original Game Boy, heating up the area where the ribbon cable meets the screen with a soldering iron will not fix it.  I was able to get the lines appear some of the time by bending the ribbon on the bottom forward quite a bit, but this was obviously not a solution that would work in the long term.  Scratch one Game Boy Pocket.

I was not dispirited by this disappointment, and I knew that my local vintage gaming shop had an Original Game Boy, and I bought it off them for $20.  It was a bit dirty, the screen protector needed replacement and I could see that dirt had found its way onto the screen, but nothing that my used toothbrush and can of compressed air couldn't fix.  Fortunately the backlight I acquired can work in either a Game Boy or a Game Boy Pocket, and can fit inside the area for the screen without cutting.  Unlike the Pocket, the screen does not come totally off the PCB (the Game Boy has two PCBs).  The ribbons are soldered to the PCB, and you need to lift the screen up enough to get at the layers but not so much that you rip the ribbons from the PCB.

People online said that removing the layers from a Game Boy's screen was easier than the Game Boy Pocket's screen.  Unfortunately, I found it to be six-of-one, half-a-dozen of the other.  The inner layer did not come off easily, I had to peel it off pieces at a time and probably left razor nicks in the glass.  When I put it back together, I found that I did not have dead pixel columns.  Instead, the lower right corner looked like I had cracked it when I peeled the last of the layers off.  It looked similar to how a broken pocket calculator's LCD looked.  The rest of the screen functioned normally.  Scratch one DMG Game Boy.

The Game Boy after the back-light was installed, I threw out the Pocket before I could take its picture.

In one day I had essentially destroyed two great vintage video game systems.  However, I was still undaunted and determined to mod a hand-held system successfully.  Ten years ago I had bought an Afterburner Kit for my Game Boy Advance.  The complexity of trying to install the front light in my GBA put me off trying it, and once the front-light GBA SP came out, I bought one and the Afterburner went into my miscellaneous console stuff drawer.  Occasionally I would pull it out and contemplate installing it, but I would look at the lengthy instructions and turn back to my backlit GBA SP.  However, determined to have something to show for all my modding efforts, I grabbed a lightly used GBA I acquired and went to work.

The Afterburner is a PITA to install, no bones about it.  The hardest part for me was scraping down the plastic in the screen area.  All those little bits of plastic tend to create dusty conditions that tend find their way in between the screen.  I did not use a dremel because I did not know if I would carve too much and create holes in the front of the case.  That was a mistake.  I apparently lost the included 44 ohm resistor that goes to reduce the screen brightness.

They also give you these really tiny wires, which were difficult to strip with my wire stripper.  In addition to the front light, there is a piece of anti-reflective film that is supposed to go between the front light and LCD screen. Getting this thing on the LCD without bubbles forming was impossible.  Snaking those wires around the PCB was a miserable experience, and soldering the wires to the tiny potentiometer to control screen brightness and mounting it to the case was a miserable experience.  When everything was finally done, the case did not have the same snug fit as it did before I touched it.

I installed the backlight and found the result to be terrible.  The screen looked totally washed out and I had a hard time making out objects on the screen.  Game boy games were a little easier to see.  I thought installing the potentiometer would improve things, but it really didn't.  It was easier to make out the screen from an angle than from a head on view.  I thought I may have screwed up the AR film somehow.  I opened up the system, fiddled around with with and found that things looked better when the AR film was not present!  Maybe my AR film was defective or maybe I lost the proper layer in the last ten years.  I reassembled the GBA and found the results to be more tolerable, although it pales in comparison to my back-lit GBA (for which I had traded in my front-lit GBA).  Unfortunately when I was playing around with the front light and AR film, I had caused a few, quite visible, scratches to appear on the front light.  There is a bit of dust on the bottom part of the screen, but still I consider this mod much more successful than my Game Boy backlight mods.

The Game Boy Advance after the front-light was installed, the horizontal lines are a camera artifact.

The same system at an angle, you can see the scratches and dust, but the graphics are clearer than they appear.

Lessons I have learned from these experiences:

1.  Use thin wires, but thick enough to strip.

2.  A dremel is a wonderful tool, worth every penny.

3.  Have a safety razor handy.

4.  See through consoles help with threading wires.

5.  Have a spare screen protector ready

6.  If you don't break your Game Boy or Game Boy Pocket screen installing a back light, consider yourself fortunate.

7.  A dab of hot glue is not an evil thing.

Battery Life in the 8-bit Game Boy Line

When the Game Boy was released in 1989, it was the first portable video game system using interchangeable cartridges.  (While the Microvision had been released in 1979, the games themselves attached to the base and provided controls and CPU as well as program code).  In the palms of the player's hands they had much of the power of the NES.  However, its rivals the Atari Lynx, Sega Game Gear & Nomad and the NEC Turbo Express, could have easily eclipsed it with their color screens.

The Game Boy had two huge advantages over its rivals.  First, it came with the killer-app pack-in, Tetris.  Second, it had far superior battery life to any of its rivals.  In this post, I will discuss battery life among the four members of the 8-bit Game Boy line, the original DMG Game Boy, the Game Boy Pocket, the Game Boy Light and the Game Boy Color.

1.  Game Boy DMG-01

The DMG-01 takes four AA (LR6) batteries and there was an official Rechargeable Battery Pack, DMG-03, available at launch, that could provide portable or AC power.  Regular Alkaline AA batteries are rated to provide a nominal 1.5 volts and 1800-2400 milli-amperes per hour (1A = 1,000mA) depending on the energy drain of the powered device.

The DMG doesn't tell you directly everything you need to know about its power requirements.  On the back of the DMG, the text states that the DMG is rated for 6 volts and 0.7 watts.  If you look in the Game Boy Owner's Manual, (p.12) you will see that this is not the maximum power consumption for the device, just the approximate usage.  Power consumption depends on what game is used and what it is doing.  The manual gives approximately 15 hours on 4xAA, but I have seen other estimates of 35 hours.

Four out of five of the launch titles for the DMG, Alleyway, Baseball, Tennis, Tetris would have required fairly little power.   These small (32-64KB) games only tend to animate a small portion of the screen, leave lots of undrawn "white space", do not use extra RAM in the cartridge, are often silent or do not always have music playing and rarely scroll the screen.  The fifth launch title, Super Mario Land, is a substantially more complex game and would have a greater power draw.  Larger (128-512KB) and more complex games after these launch titles would almost certainly draw more.

Back to our DMG, we need to determine the amperage the device requires.  Fortunately the relationship between volts, amps and watts is simple :

W = V x A

Dividing the wattage, .7, by the voltage, 6, we get .11666A, or 116.66mA.  If we look at the rechargeable battery pack specs, we see that it provides 150mA, confirming the ampere requirements for the DMG.

The DMG and its successors connect its batteries in series so that the output voltage is the sum of the output voltage of each individual battery.  So four 1.5v AA batteries will give a voltage of 6v.  Unfortunately, the mAh available to the Game Boy does not increase with extra batteries.  If the batteries were connected in parallel, it would increase but the voltage available would only be 1.5v, which is nowhere near sufficient to drive the device.  Thus you get a tradeoff, either you increase the voltage or the current that can be provided, but not both.  

The rechargeable battery pack also tells us that it provides 4.8v to the Game Boy.  Rechargeable AA batteries like NiCd and NiMH batteries provide a nominal 1.2v per cell.  NiMH was just coming on the market in 1989, and the rechargeable battery pack used NiCd batteries. However, the Game Boy is fairly tolerant of the variance between 6v and 4.8v, probably because it uses 5v logic.  Besides, depending on the quality of the Alkalines being used, that 1.5v per cell may be very nominal indeed.  Moreover, the voltage of an alkaline declines over time, whereas a modern NiMH battery's voltage remains much more constant until it reaches the point of discharge.

Now we come to the issue of mAh.  Consider the following datasheet :

http://data.energizer.com/PDFs/E91.pdf

As we have determined, the Game Boy requires an average of 116.66mA to operate.  According to the Milliamp-Hours Capacity, at that amperage requirement the battery can provide approximately 2400mAh.  If we divide the mA by the mAh, we get 20.57 hours.  Nintendo's estimate may have been a bit conservative here, but they could have been thinking ahead for the more complex games to come.

Nintendo was not only introducing a new video game console, it was introducing a new video game concept. It had to convince buyers that they should buy an expensive hand-held video game machine and its cartridges.  It also had to show that the simple games from Tiger Electronics simply were not good enough.  First impressions counted a great deal, and Nintendo could not afford to fudge the battery life figures too much.  This was especially true because of how crucial battery life was to the hand-held video game market.  Nintendo's success rested in no small part on its battery life.  You could get 15-20 hours out of a Game Boy on a fresh 4-pack of batteries.  Its competitors required 6 batteries and could give you six hours at best.

2.  Game Boy Pocket MGB-001

The Pocket was the second iteration of the Game Boy line, released in 1996.  This was a comparatively slimmer device, as its name implies.  The Pocket takes 2xAAA (LR03) batteries and has power requirements of 3v and 0.7W.  Thus, although the Pocket's logic may require fewer volts to operate, it requires double the amps, 233.33mA.  Therefore the actual power to operate the Pocket is unchanged from the DMG.

The official Game Boy Pocket A/C Adapter from Nintendo, MGB-005, outputs 3v and 300mA.  A similar third-party adapter from Hori outputs 350mA.  The Pocket A/C Adapters are to be used with the Game Boy Light and Color.  In Japan there was a rechargeable battery pack for the Pocket.

The use of AAA batteries kills the battery life of this machine.  An Alkaline AAA battery has the same voltage as an AA battery, 1.5, but only provides 850-1200mAh.  There is only about half the energy available to the Pocket as there is to the DMG.  I have seen quotes of battery life of 8-10 hours for the Pocket.

If we take the datasheet here as a guide :

http://data.energizer.com/PDFs/E92.pdf

We can see that at 233.33mA, we are only going to get about 700mAh out of our good AAAs.  This gives us a pathetic 3 hours.  Perhaps Nintendo was measuring it against the titles that were available in 1994-1995, such as Kirby's Dream Land 2 and Donkey Kong.  The strict approximation doesn't seem to hew to the reported battery life, which demonstrates that the Nintendo or the battery makers were treating the issue of battery life very conservatively.

3.  Game Boy Light MGB-101

The Game Boy Light, released only in Japan, functions like the Game Boy Pocket with a switch to activate an electro-luminescent backlight.  The Light uses 2xAA batteries and boasts 20 hours of play without the backlight and 12 hours with it on.  The power requirements have also decreased slightly to 3v, 0.6w.  Thus it requires an average of 200mA to run.

According to the datasheet, at 200mA we have approximately 2000mAh.  If we divide the mA by the mAh, we get about 10 hours on a pair of AAs.  One hopes that the stated power requirements were taking the backlight into consideration.

4.  Game Boy Color CGB-001

The Color has the specs of the Light without the backlight.  I have seen quotes of battery life of 20-35 hours.

Now the Color has the same power ratings as the Light, but this time it has a color screen, three times the RAM and a CPU that can run twice as fast as the Light, Pocket and DMG.  The games themselves are typically larger, from 1-4MB.  I suspect that the battery life is more impressive if it runs monochrome Game Boy games than if it is running Color Game Boy games because those extra features are not being used.

Compared to the original DMG, the Color seems to have less life.  However, the Color can run on 2 AAs whereas the DMG requires 4.  I would say that with 4 AA batteries (meaning you need to replace the batteries once), you can probably get the same amount of playtime as you would with a DMG.

The videos here may be very instructive :

https://www.youtube.com/watch?v=XsU4AcYhjy8

https://www.youtube.com/watch?v=VgKdEa06qUs

The video maker in his first video gives a battery life of 31hrs 12mins for a DMG and in the second video 35hrs 45mins for a Color.  In the later video, the relatively short time for the Game Boy is because one of his children turned it off prematurely.  However, both systems were running monochrome Game Boy games, and I cannot tell for certain what game was in the DMG, but it appears both videos used the same game in the DMG.  I think it is Super Mario Land.  (For the Color it was Top Rank(ing) Tennis).  Super Mario Land has an attract mode, but Top Ranking Tennis has animation and music on its title screen, so the cartridges seem pretty fair.  However, if a true Color game were being played, I would certainly think that the time would be significantly shorter.

Game Boy Pocket - The Pure Monochrome Experience

I have recently acquired a Game Boy Pocket.  It is one of the revised models, with a blue case and a power LED.  The Pocket is a slimmed-down version of the original Game Boy.  Its chief benefit is that its case is smaller and less bulky.  It has a similar screen size but slightly smaller controls and speaker.  It plays the exact same titles as the original Game Boy.  It doesn't have a backlight, but one can be added today with mods.

The screen is the best feature of the Game Boy Pocket.  It has better contrast than the original, a better monochrome gradient and virtually no ghosting with moving images.  The original Game Boy screen, due to pixels with long transition times, would show ghosting in moving images. Some games have effects that require a monochrome screen, like the mountains at the beginning of the Cloud Castle stage in Castlevania 2 : Belmont's Revenge.  On any color screen, the mountains will flicker more than on a monochrome screen.

When I play a game on the original Game Boy, I have asked how I ever put up with that awful screen when I was a child.  I do not ask the same thing about the Pocket.  Another plus to the Pocket is that it does not suffer the missing vertical lines issue of the original Game Boy screen (fixable, but still).

The sound has been criticized as not being as nice as the originals', and from the headphone jack there an annoying background noise that is audible when headphones are connected through the headphone jack.  The original Game Boy just has hiss.  Stereo panning support was a touted feature of the Game Boy when first released, but by the time the Game Boy Pocket was released in 1996, there were few music and sound effects in games that supported stereo sound.  Most people used the built-in speaker, even when headphones could be used.

The controls on the Game Boys and Game Boy Advance feel like real D-pads, the controls on the Game Boy Advance SP feel more like microswitches.  The controls on the Pocket are not so much smaller than the original to really feel like you have lost precision control.

Backlighting kits exist for the Game Boy Pocket, typically kits work for the original and the Pocket.  The best ones are from nonfinite electronics and kitch-bent.  Installing a backlight in the Pocket is a bit trickier than in an original Game Boy, here is a good video showing how it is done : http://www.youtube.com/watch?v=qUUEVWbLoS8  A Youtube channel now called 8-bit guy suggested spraying WD-40 into the crevice between the layers and the glass once you have pulled up a corner.  He says this really helps remove the adhesive bond.  Having irreparably damaged a Game Boy Pocket's screen after trying a mod without WD-40, using WD-40 may be a good idea.

The only real disadvantage to the Pocket is its anemic battery support.  The original Game Boy uses four AA batteries, and the Game Boy Light, Color and Advance all use two AA batteries.  The Pocket uses two AAA batteries.  An AAA battery has about half the rated mAh as an AA battery.  While this is OK for playing official cartridge games without a backlight, it is far from ideal for using multicarts like the EMS GB 64MB Smart Cart or the new Krizz Everdrive GB.  A backlit GB requires more power than a non-backlit GB, even with modern LED backlighting.  Multicarts require more power than standard carts

In my opinion, Alkaline batteries may be okay for a backlight, but they do not have sufficient power for a multicart.  On the EMS card, the cart may work for a while with fresh, name-brand batteries, but after a short time they will not be able to power the card, which will lead into an endless reset loop.  Alkaline batteries experience a far greater mAh drop over use than Lithiums.

Perhaps the EMS cards made after June, 2010 (as shown on the back of the card, mine is 0908) are better with this.  More active screens will appear lighter than less active screens.  NiMH batteries tend to support 500-800 mAh compared to the 1250-1000 mAh of the Energizer Ultimate Lithiums.  1000 mAh average is probably the maximum you will get out of name brands, but I hear they can provide a much more reliable current than an Alkaline.  I would strongly recommend using the Sanyo Eneloops or other high end brand.

There are AC adapters for the Gameboy Pocket.  The right adapter for the Pocket or the Color uses 3V, 300mA and has a positive tip.  Radio Shack's Adaptaplug A should fit.

My EverDrive GB will work in my Game Boy Pocket with Sanyo Eneloop rechargeable AAAs.  The screen contrast will lighten somewhat when it is loading or flashing a game, but it will complete the process.  When the game is playing there will be no need to constantly monitor the contrast dial as I would with the EMS Flash Cart.