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Altera_Forum's avatar
Altera_Forum
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10 years ago

Help a Noob in trouble

Hi every one, I'm excited to get my hands on the DE0 board. I just bought a couple of LED's and some toy motors and was hoping to turn them on/off with this board. My approach was using the Nios II in assembly since i have learned that in my class. As i connected the GPIO port, i was able to set it as an output port to cycle some signal such as 1 or 0. But the problem arises that the signal from the GPIO pins don't have any power! Other than some specific Pins that supply +5v which cannot be controled through the Nios II. My question is what is the best method to control, lets say LED's on/off ? (And i mean by external LED's not the one on the board itself). Can i program the GPIO in such a manner to send signals to do such a thing? Or do i need some seperate hardware that boosts the signal from the GPIO? My code is attached.

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  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    10 years ago

    You can indeed use a DE0 to drive motors, by not by itself. FPGA pins are logic levels. They aren't designed to provide enough power to run motors etc. You will need a simple motor driving circuit (diode + transistor + resisters) There are several tutorials for driving motors off of microcontroller GPIOs. The same principles should apply to an FPGA. Make sure you understand the principles involved. Don't just blindly use the values the tutorials use. Do the calculations based on the output current limit of the FPGA pins. It's very easy to blow the outputs on your FPGA (you might have done so already).