katsumbhong
Offline
Taichung, Taiwan
katsumbhong wrote:
Jazzmarazz wrote:

Well, no. The tutorial describes connecting it to both the +5v regulated pin and to ground respectively. The worry is actually current, not voltage. Current should be very similar in each case, but I cannot vouch for exact values at this time. If anything, I can imagine the DMG as having a larger current. Start with a 330Ohm resistor and either lessen or increase to another resistor value depending on the brightness.

This. My brain stopped working apparently. Resistors raises resistance, it does not drop voltage. Sorry for the double post

Last edited by katsumbhong (Jan 17, 2014 2:39 am)

Jazzmarazz
Offline
Michigan

This is not the solution I suggested, but If it interests anyone it never hurts to learn! big_smile
http://en.wikipedia.org/wiki/Voltage_divider

bitjacker
Offline
Alive and well in fucksville

320 ohm resistor enough?

Last edited by bitjacker (Jan 17, 2014 2:30 am)

Jazzmarazz
Offline
Michigan
bitjacker wrote:

320 ohm resistor enough?

You mean to begin with? Most likely.

bitjacker
Offline
Alive and well in fucksville

if i want it super dim what would be the second value to use?

Jazzmarazz
Offline
Michigan

Any higher value, or if you only have 320 ohm resistors, put two in series.

MaxDolensky
Offline
Alabama

Just an FYI deal, but I think that since this screen is meant to perfectly fit a Gameboy Color, it won't perfectly fit over a DMG screen.

bitjacker
Offline
Alive and well in fucksville

shoot. for the sake of experiment it will be good enough for now. maybe if it looks cool a bigger one  with built in resistors could be made someday?

Jazzmarazz
Offline
Michigan
bitjacker wrote:

shoot. for the sake of experiment it will be good enough for now. maybe if it looks cool a bigger one  with built in resistors could be made someday?

Kitsch never sleeps, so I can see it being a possibility.
I front lit an original Gameboy with an AGB-101 screen once and it looked terrible because of the lines on the lighted panel, but it did not wash out the pixels very much at all. I believe I had the screen inverted though.

bitjacker
Offline
Alive and well in fucksville

how does one invert the screen if needed?

MaxDolensky
Offline
Alabama

You either install the lens flipped a different way (I believe it's toothed-edge-faces-screen) or if you are talking about inverting colors, I think that requires using a different color scheme in LSDJ.

rygD
Offline

look up "biversion".  This is a combination of both ways to invert the screen

lvlzero
Offline
Baja California

Please kitsch tell me that you will get more GBC front lights later. I want to have a frontlit cgb this first half of the year.

bitjacker
Offline
Alive and well in fucksville

Damn should have ordered biversion kit.
i may just go get another cgb
i cant have enough gear

Last edited by bitjacker (Jan 19, 2014 11:36 pm)

thedimitry
Offline
Spain

I looked at Kitsch's frontlight pic closer and thought that the contrast pot might not be all the way up on that GBC. It's located under the batteries compartment and is usually hidden by a sticker of the same colour as the shell. Adjusting it might make the screen sharper and easier to read.

Kitsch, in the tutorial the solder points seem to be the same as for the SP frontlight. Aren't those only 3V and unreliable? I remember they made the backlight flicker with the sound on a GBP (they share smiliar PCB elements with the GBC). Why not use the stable 5V from the cartridge connector? Just wondering. Thanks.

MaxDolensky
Offline
Alabama
thedimitry wrote:

I looked at Kitsch's frontlight pic closer and thought that the contrast pot might not be all the way up on that GBC. It's located under the batteries compartment and is usually hidden by a sticker of the same colour as the shell. Adjusting it might make the screen sharper and easier to read.

Kitsch, in the tutorial the solder points seem to be the same as for the SP frontlight. Aren't those only 3V and unreliable? I remember they made the backlight flicker with the sound on a GBP (they share smiliar PCB elements with the GBC). Why not use the stable 5V from the cartridge connector? Just wondering. Thanks.

The solder points are reliable, as far as I can tell. I did a quick recording test comparing a GBC with a frontlight installed using those points (SP frontlight, not a Chinese clone or kitsch's product which should be here in the mail for a review soon) and I compared it to my Gameboy Light, which I use to record with and play live.

http://imgur.com/C4BWaVb
I use my GBC daily for playing Pokemon Crystal version, and the guts of this GBC have had a frontlight installed since... probably 3 years ago back when Bibin showed his face more, he was nice enough to talk to me about Sonic hacking stuff on IRC and walk me through some of the mod. You can see that the sound on a GBC with no prosound is comparable to a GB Light with the backlight on, prosound being used. Both Gameboys were recorded with their pots cranked all the way up, and I tried to record them as close to peaking in Audacity as possible.

What this hints at, in my opinion, that the power draw is pretty stable from the 3V line. Part of my other reasoning for this is that the battery indicator LED is always in tune with how quickly the batteries drain even with the light, and for me the screen has never ever flickered or popped or shown any lack of brightness. Very consistent piece of kit (the SP frontlight), cannot wait to try doing some Pokemon Crystal runs on kitsch's frontlights and see the difference. smile

Last edited by MaxDolensky (Jan 20, 2014 4:45 am)