LEGO mindstorms and FPGA

What are your goals in the substitution ?? Do you want to run the programs from the RCX on the JOP ? Do you want to create new program in a java environment ?

The FPGA is almost insignifcant if you are only interested in software.

Mart> Yesterday I bought a LEGO mindstorms set (getting infantil in my old

Not that I've seen.

Some verilog code for servos etc here

Alex

That's a nice project. They did implement voltage sensing of the motor generated voltage during 'off' of the PWM to get some feedback. That's exactly what I have planned for the motor control.

Martin

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Fun :-)

No, I want to program the robots in Java.

The FPGA is used to interface with the motor and sensors. It's simple to implement the ADC for the sensors in the FPGA.

I will put the schematics for the sensor and motor interface with some VHDL code on a webpage when I got it work.

Martin

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I did something of the sort way back when for HO train engine control. It involved a few diodes, a quad op amp, SCR, and the odd component including a transformer. The idea was to use the raw rectified unfiltered AC, which shut off the SCR and allowed the diode etc to sense the speed, and then turn the SCR on again. I wish I had kept schematics. It worked quite well 25 years ago. I even cobbled in a braking mode somehow.

by

The LEGO sensor interface to the FPGA with a sigma-delta ADC is completed. I've set up a web page with the schematic and the VHDL code:

The motor control, camera input and hopefully a nice roboter example will follow.

Comments and suggestions on this solution are welcome ;-)

Martin