I have a video for you guys today. In the video below, I demo the motor controller prototype for you guys. I have temporarily relocated to California and I couldn't bring the RC Car frame with me here. The frame has the main DC motor on it, and I haven't been able to take it off, so to bring the motor, I would have to bring the whole frame which is way too big. As a result, you will see in the video that I don't have a motor to connect to the motor controller. I did manage to PWM the motor using the C2000 LP before I left for California, so that does work. I am using a pair of LEDs connected in parallel with opposite polarity to prove that current does run in both directions. Sorry for the lame demo, motor spinning would definitely be cooler than a pair of LEDs blinking.
On the other hand, I am going to start working on cracking the RF transcievers I have. As I mentioned earlier, the RF modules came with 0.05" pitch header connectors which are useless, so I had to build a PCB using Eagle to make a simple RF Module Breakout board. Renderings shown below. I actually just ordered these boards from OshPark an hour ago. I am very excited since these are the first ever boards I have ordered! For three of these boards, I paid only $5, so that is a good deal. For my next PCB, I want to try out Seeed Studio. The next board I will build will be quite large since it will incorporate the motor controller, headers for the C2000 Launchpad to sit on, and other pins to connect the external peripherals (Servo, LEDs...). I reckon if I use OSHPark to get that PCB done, it would cost about $40-$50 which is a lot. Seeed studio is much much more reasonable and I got this tip from a colleague at work (shout out to Stephen!)
OshPark PCB Top rendering.
OshPark PCB Bottom rendering.
I have an Aardvark SPI/I2C Bus monitor with me here, and for initial protocol testing I will be using it. Later after I figure out how the communication carries out, I will start working on the drivers for the C2000 LP. The protocol is SPI and I am not worried much about that, what worries me is the abundance of registers in the RF Modules and the 100-page datasheet. So I will need to figure out how I need to set up the internal registers in the RF modules (set one as a receiver and the other as a transmitter and tune them to correct channels, set up error connection, etc.....) The advantage of Aardvark is that I will be able to send commands to the RF Module over SPI from my computer. Therefore, I will be able to see all the communication taking place on my computer in a terminal which makes debugging much easier. I will keep you updated.
-Anil
No comments:
Post a Comment