Mindboards

Hi all, I'm trying to send a simple numerical value from RealTerm (terminal program) to the NXT via Bluetooth. According to Lego's Bluetooth SDK, the Write command follows two bytes that specify the length of the package: Length bytes: LSB followed by MSB (e.g. 6 bytes: 0x06 0x00) Byte 0: 0x00 or 0x...

t simply doesn't know when you've changed to another channel, so it won't try to go back to the first one. Thanks, Steve. It's what I thought. That's why I mentioned previously that I tried to look for a block that addresses the remote functionality but couldn't find one. Since the remote program u...

Hi everyone, I had been working for quite awhile on a project that used Matlab/Simulink and nxtOSEK, and involved quite a bit of custom hardware. It was an utter pain to get everything to work. Now that it's finished, I would like to build some simple models for a bit of fun. I have constructed a ve...

I would assume that Simulink takes care of that, though I have nothing to base that on. Yes, you are quite right. Simulink and Matlab do initialise variables with values of zero. Oh yeah, I found the problem! The raw sensor data is fed into a series of kinematic equations that are based on the phys...

Matt, I program in Simulink with additional Matlab code. The model is then compiled for nxtOSEK, so I don't have any low-level control of things such as threads. Indeed, I wouldn't know how it could be done even if it were possible. My programming knowledge is adequate for an engineering student, bu...

Hi everyone, I am using Simulink, Matlab and nxtOSEK to develop an adaptive control program to guide an NXT vehicle along a predetermined path. Using modelled dynamics, the algorithm works rather flawlessly in simulation on the PC. As is often the case, reality is quite the opposite. Keeping the sta...

Andy, you identified the problem straightaway! The motors in the simple calibration program are on brake mode while the motors in the adaptive control program are on coast/float mode. I didn't realise there was such a stark difference between the two motor settings. Thanks for your insight and for t...

Hi there, I'm using Simulink/Matlab and nxtOSEK to design an adaptive control algorithm for the NXT. For those who aren't aware, nxtOSEK uses some rather old leJOS drivers to interface with the sensors and motors. Now, I've been wondering for some time why my vehicle cannot maintain a smooth run but...

I've removed the 82B715 and replaced the pull-ups with 82 kohm resistors. There is still no interaction between the AVR and NXT. Using a digital multimeter, I measured the voltages of SDA and SCL to see if they're pulled low to signal a START condition. They each measured 4.4 V and remained pretty c...

I forgot to respond to this part in your earlier post. You would use a pair of those ICs, one at each end of longer wires. It would be like this: NXT > 82B715 > Long Wires > 82B715 > I2C device. A re-read of the documentation has indicated that a pair of 82B715s is necessary for the I2C system to fu...