Current Draw Tests on Moded GBA (AGS 101)—Original Cartridge/EZ-Flash IV

Hello Everyone,

I have an original GBA (40-pin model) and I've replaced the original screen with AGS 101 model b screen that I've bought on aliexpress. Both screen and adapter are model b and the small wire from the adapter is soldered to DA1. Everything works perfectly—there is no ghosting or interlace problems but I've noticed that rechargeable batteries last under 10 hours with New EZ-Flash IV. I've decided to measure the current draw to see exactly how hungry is EZ-Flash IV.

Test Results:

GBA + original cartridge = 120mA

GBA + EZ-Flash IV = 200mA in menu and when loading a game into SRAM; around 210-220mA when in game (loaded either from NOR or SRAM), however there were instances when the consumption briefly jumped to 250mA (during animations)

Conclusion:

EZ-Flash IV is very power hungry as it uses 100mA during normal operation—it is almost like you have another GBA on top of the first one. One other thing that I've noticed is that this flash cart is very sensitive to voltage when it comes to writing games to NOR. I only use rechargeable AA batteries and two of those have a bit more than 2.4V, which isn't enough to write the games into NOR—what happens is that it looks like the game is being written to NOR, but when the process completes there is simply nothing there. I was only able to write games to NOR by using GBA power adapter (3V) that's plugged into a wall socket.

One other problem with NOR is that while I can load a game from it while having less than 2.4V (red light on) I can't load savegame properly once I'm inside the game—it loads the savegame with all kinds of graphical artifacts and sound goes awry. If the light on GBA is green (above 2.4V) the savegames load without problems. As the rechargeable batteries relatively quickly drop below 2.4V playing games from NOR is simply not practical for me because of these issues, so I'm sticking with loading them into SRAM on each play session.

 

@Shadow#1

I would if I had Everdrive GBA X5

Anyway, I've decided to do these tests because I couldn't find any info here or elsewhere about GBA (AGS101)/EZ-Flash IV current draw. I've seen on other threads that other people are also interested in this info, so here it is. I hope it helps someone troubleshoot their problems (especially NOR writing problems as I've seen quite a few of those).

 

Localhorst86,

yes, Everdrive GBAs are quite pricey. I've already spent almost 100$ for screen, adapter and EZ-Flash IV and I don't want to spend another 100$ on Everdrive when EZ-Flash runs all of the games just fine. It would be interesting to find out how much current Everdrive draws but somebody else will have to measure it.

On a side note, I remember that GBA without the wire soldered to DA1 for maximum brightness needed 100mA with original cart, and with the soldered wire the consumption jumped to 120mA. It's now actually a bit too bright for my taste, but at least I can experience Castlevania: Circle of the Moon properly (that has to be the game with the darkest gamma setting in a whole GBA library).

JCR1,

I haven't put any of the emulators on cart, so I wouldn't know. The whole purpose of GBA modification for me was to be able to experience games natively on a better screen. If I was interested in emulators I would probably buy some handheld that comes with them preinstalled (there are a lot of those on aliexpress or ebay).

 

Hi Essometer,

I've measured it by connecting multimeter in series with batteries (like everyone does).

I've tested the current draw today and I took some pictures, so people don't think I'm making up measurments:

1) GBA with no cartridge = around 90mA
2) GBA + Ez-Flash IV (in menu) = around 170mA
3) GBA + Ez-Flash IV (M&L: Superstar Saga) = around 200mA
4) GBA + Game Boy Color game (Super Mario Bros Deluxe) = around 120mA



There are two excellent posts on imgur about various models of Game Boys and their power draw if anyone is interested, however they don't contain EZ-Flash IV measurements:

https://imgur.com/a/BVQvn#gayYiLI
https://imgur.com/a/aLSxD

What I've learned from the test data in those imgur posts is that there is quite a difference between 40pin and 32pin GBA models regarding current draw:

1) Stock 32pin GBA with GBA game = 64mA
2) Stock 40pin GBA with GBA game = 101mA

 

Hi Bazahazano,

I have original EZ-Flash IV—you can see it on the last photo from my previous post. Thanks for sharing your results with Easy Flash IV Reform, it seems to be more power efficient as it draws around 50% less current than the original EZ-Flash IV on my system. I found it interesting how there is only 10mA difference between my GBA at full brightness (without inserted cart) and your GBA SP at full brightness (without inserted cart), but the difference becomes quite noticeable with original games—my GBA draws around 30mA per game while yours draws only 10mA. It would be interesting to find out how much exactly would my original EZ-Flash IV draw on your system, and if power draw of original carts that I've mentioned is any indication, it should draw less current than it does on my system.

 

Hi Bazahazano,

interesting results. I bet that when you add AGS101 screen at full brightness that the overall consumption will jump around 20-25mA. However, I could be wrong as I don't know how the 12v supply for the screen is going to impact the overall battery consumption. I would say that there isn't a noticeable difference between Easy Flash IV Reform and original EZ-Flash IV regarding the current draw (on 40pin GBAs) when taken in consideration that you yet need to add AGS101 screen.

Keep us informed how the mod goes.


Hi Migles,

there is no difference in current draw if the game is run from NOR or PSRAM. I've also thought that there is going to be a difference as I've read somewhere that NOR is more battery friendly but after testing this myself I found this presumption to be wrong.