I’ve been working on an Arduino project involving a board with an AVR 1284P and FT232rl for a long time. It’s my kickstarter project and its in the final development. I need help figuring out where some of the power is going.
So my device piggybacks onto an Xbox 360, and they both share a power source of 2 AAs. As soon as my device is connected the LEDs on the Xbox 360 controller dim greatly. This has only started after I switched the AVR on board to a 1284P from a 328P.
When I measure the current draw in series with my device the the multimeter is showing between .1 and .2 ma (or .1 or .2 on the 20m setting). I find it strange that as soon as I changed the device’s AVR to a 1284P it started to affect the Xbox Controller. I’m not an EE but could it just be that the device is stealing a lot of the Power Supllies Potential Energy (so basically its voltage?) I’m starting to think that it’s not actually a power hog its just that the controller in some way is not allocating enough voltage/current to its LEDs with the added strain. I believe this because if I ground the Xbox Controller LED with my device the LEDs shine brightly. Would this demonstrate that it actually isn’t the lack of current but something else.
Also, If I connect the Xbox Controller’s USB cable the LEDs work correctly and shine brightly. This would be because the battery packs 500ma supply potential plus the 500ma of the USB can supply enough current for the entire load? The LED shines with 1.71 volts with my device attached and with 1.86 with it not attached. This would indicate a current shortage?
My first thought was the pull up were leaking current into the controller’s ground on some of the analog buttons but after disconnecting all other connections besides VCC and Ground the change was little.
The controller still works correctly, just the Player LEDs are extremely dim.
If some of this doesn’t make sense please ask me in more detail. This project is open source and I can also supply schematics and other info if need be. The concept is pretty cool and I’ve already created a custom library to interface will all of the controllers buttons and peripherals.