Comments on: BrushBot Comm Board design

By: Pete Skeggs

Pete Skeggs — Thu, 04 Feb 2010 05:57:54 +0000

Awesome work Monty! You get a gold star!

By: montyg

montyg — Tue, 02 Feb 2010 07:51:07 +0000

I was briefly tempted by the QFN package, but I worried that I might scare people off. Not that this current version with SOIC’s and 0603’s won’t. I figured I’d keep this one hand-solderable, though the hot-plate/toaster oven method is definitely the plan.

By: Laen

Laen — Tue, 02 Feb 2010 05:55:11 +0000

The ATTiny44 comes in a QFN package as well, which could open up some room, and with the laser-cut solder paste stencils, they’re really no harder to solder..

By: montyg

montyg — Mon, 01 Feb 2010 17:26:40 +0000

1.) No pad for V+, at least not yet… I wanted to stick one at the bottom (there’s no room at the top, after all), but V+ isn’t routed down there yet. I might be able to route down under U1.

2.) I really wanted to add a couple transistors, but I’d have to grow the board to do so. If I do so I’ll stick in protection diodes too, and preferably base resistors for noise protection.

The ZipBot chassis is big enough to allow for growing the board, which I was avoiding to keep the cost down, but it may be worth doing for the motor control and a header for battery connection. Oh, the feature creep!

By: plskeggs

plskeggs — Mon, 01 Feb 2010 16:05:25 +0000

1. Is there a pad for V+?

2. Did you decide not to add motor drive capability? I suppose it could be hacked on using an NPN transistor, with its base connected to one of the unused AVR pins through a current limiting resistor. The emitter could go to ground, and the collector to the – terminal of the brushbot’s motor…. then wire the grounds of this board and the brushbot together.

By: montyg

montyg — Sat, 30 Jan 2010 20:41:16 +0000

Good point. My main interest in Arduino compatibility was to make it easier for those new to the group w/o much microcontroller experience to get started, but, we got by pre-Arduino and we can help others get started with gcc, CodeVision, or something else. We can provide skeleton code that takes care of the hardware setup and transmitter modulation and directions on how to compile and download code.

By: Pete Skeggs

Pete Skeggs — Sat, 30 Jan 2010 18:28:07 +0000

Considering how quick and dirty this is supposed to be , I wouldn’t worry too much about Arduino compatibility.

By: montyg

montyg — Wed, 27 Jan 2010 09:37:17 +0000

Thanks for the links Chris. See any indications on how well these guys would perform with many transmitters in the same area?

By: Chris Arnesen

Chris Arnesen — Tue, 26 Jan 2010 13:49:16 +0000

I mentioned the cheap basic RF wireless solution I stumbled across once… Here are links to the TX/RX boards I found. Not too bad for less than $10 per TX/RX set:

315 MHz – TX: http://www.sparkfun.com/commerce/product_info.php?products_id=8945
315 MHz – RX: http://www.sparkfun.com/commerce/product_info.php?products_id=8947
434 MHz – TX: http://www.sparkfun.com/commerce/product_info.php?products_id=8946
434 MHz – RX: http://www.sparkfun.com/commerce/product_info.php?products_id=8950