[HELP] Power Functions BT Receiver

[vmckee]

Codefox, glad you're still working on this. I'm excited to see the next version. Where do you find the HM-06 for sale and what is the benefit of the new motor driver? This version looks quite a bit more challenging/expensive and will probably be a lot more intimidating for smd and avr noobs (like myself), but I know it has much more promising capabilities.

[Phoxtane]

Is there a BOM for this? I recently discovered that I could request samples from Texas Instruments and Maxim Integrated, so I'm curious to know what parts, if any, I could test out with this device.

[codefox421]

A quick update: I've designed an enclosure for the modular receiver and put in an order for it through shapeways (took advantage of their free shipping promotion this week). I'm looking forward to its arrival and trying it out.

Modular Receiver Housing by Nick Iaconis, on Shapeways

I sometimes have problems with the controller resetting when rapidly switching directions. Could probably be fixed with varistors across motor outputs, but I haven't bothered.

I would love to see you do some experimentation with that. I remember witnessing it when running a prototype off of a 9V battery, but I have no doubt you're running more current through your receivers than I am mine. If you figure out a solution, let's get it into the upstream repository.

Codefox, glad you're still working on this. I'm excited to see the next version. Where do you find the HM-06 for sale and what is the benefit of the new motor driver? This version looks quite a bit more challenging/expensive and will probably be a lot more intimidating for smd and avr noobs (like myself), but I know it has much more promising capabilities.

I think this is where I got the HM-06: https://www.fasttech...ransparent-seri It looks like it's out of stock or not sold there anymore though; wish I had picked up a few spares.

The new motor driver (an LV8402GP) has about the same current capacity as the DRV8833 but can handle up to 16 volts (the DRV8833 can only handle 11.8 volts). I plan on eventually making a battery module based around a 3S LiPo (or maybe LiFePO), which will have a max voltage of 12.6 volts (or 11.1 for LiFePO), so the extra voltage headroom is necessary.

The motor driver was a little tricky to solder (I used a toaster over to get the job done), but with a good pair of tweezers, a good soldering iron tip, and some patience, you'd be surprised what you can do.

Is there a BOM for this? I recently discovered that I could request samples from Texas Instruments and Maxim Integrated, so I'm curious to know what parts, if any, I could test out with this device.

Here's a quick draft BOM: https://gist.github....4729dce3e839759 I just used digikey part numbers to save time, but most everything can be replaced with equivalent parts.

[legoman666]

I got my hm06s from eBay.

Edit: as for the voltage max of the 8833 chip, I put 6 LiPo AA sized cells in 2 parallel strands with 3 in series each, which yields a little over 12V when fully charged. The moment they're discharged at all, they fall to 3.7V each, which is just within spec.

Edited September 2, 2015 by legoman666

[joblog]

I managed to install Firmata on the ATtiny841 chip used on codefox's board.

Which means It should be possible to let Scratch communicate with his board over bluetooth and control motors (or anything else) attached to it

I don't have codefox's board but I have managed to make Scratch do this for a combination of individual ATtiny841, HC05 and dual motor driver.

The details are described here.

All that is required is that you

(i) add to the boards.h in Arduino as described in the link

(ii) take the pared down Firmata2.2 described in the link and upload it to the codefox board using a programmer or Arduino as ISP.

(I assume codefox's HC05 has a 57600 baudrate)

I found the easiest way to connect to Scratch over bluetooth was using Thomas Preeces A4S(You just need Step 3)

It would be amazing to see codefox's tiny lego brick doing all this.

Edited January 6, 2016 by joblog

[legoisfun]

Would be nice to use Powered Up remote. I think it can be used (PUP remote’ to adjust the speed: red buttons can act the same way as in original “speed remote”.

Edited February 1, 2024 by legoisfun