9th October 2004, 07:12 #1
Newbie level 4
I am doing my thesis on inverted pendulum. I am facing problem of designing a schematic diagram for a H-bridge [L293DNE] to control my DC motor.
My inverted pendulum is connected to DSP TMS320C6711, then from DSP to Matlab. My greatest problem is that I do not know how to connect my H-bridge & optical shaft encoder [connected to my pendulum] to DSP. Do you happen to have any ideas to solve my problems???
Please reply me back if you have the solutions...Thank you very much!!!!! :)[/i]
9th October 2004, 07:12
9th October 2004, 13:07 #2
Member level 3
h bridge circuit diagram
The are schematics in the datasheet http://focus.ti.com/lit/ds/symlink/l293.pdf
I used TMS320LF2407 EVM before. Like TMS320LF280 series, which is much more powerful than 2407, is optimized for motion control. My colleague used TMS320C6711, but he used it for signal processing. As 2407 is optimized for motion control, it has many built-in features for motor control, e.g. many PWM channels, on-chip position encoder interface circuitry, deadband generator, etc. But, if I'm not mistaken, in term of computational power, TM320C6000 series is a lot more higher than TMS320C2000 series.
It's quite straight forward to control H-bridge (shown in figure not really a H-bridge). As shown in the circuit, you can control (pin 1A and 2A) the motor in bi-directional. I also used L293 before for line following project, which was controlled by 8051 ucontroller. However, at the beginning, we're not successful because our motor always halted 'halfway'. After troubleshooting, we found out that the circuit was very noisy when motor was running (especially accelaration). So, we added optocoupler to isolated the ground of the digital circuit from the ground of the motor driver circuit, and after that it worked very nice. It depends on your motor power and your PCB layout technique. If the motor power is low and PCB layout is good, then probably you do not need to have optocoupler. Regarding the encoder circuit, I think TMS320C6000 series does not have onboard encoder interface circuitry. You can connect to any capture-I/O (not sure 6000 series got or not). If no, then you have to keep polling general I/O. Since 6000 series is so powerful, it should not be a problem to control a dc motor.
9th October 2004, 13:07
9th October 2004, 16:38 #3
Newbie level 4
h bridge schematic
My project is on inverted pendulum. This cart having the pendulum on top of it is connected DSP TMS320C6711 then to Matlab.
I open up both CCS and Matlab at the same time. However, when I am running my CCS , it is a success; when I type *ccsdsp* at the Command Window at Matlab, it says that it can't detect the DSP board and it says I didn't configure my board. Why is that so????
Another problem is that the are two I/O 80 pins on TMS320C6711, but how do I connect them to my L293DNE H-bridge and optical shaft encoder?How would the schematic diagram looks like to connect both of the components to my DSP I/O pins??
Please help me out..... :(
Thank you very much!!!!!!!!!!!
9th October 2004, 16:38
10th October 2004, 01:37 #4
Advanced Member level 2
h bridge diagram
I guess you're using kind of TMS320C6711 DSK or EVM. Can you pls give us the ventor of your design kit or evaluation kit? Because we don't know the details of the TWO 80-pin connectors. Also, pls state the version of your CCS and also the Matlab.
10th October 2004, 15:45 #5
Newbie level 4
l293dne for motor driver
The Matlab I used is Matlab 6; The DSP is TMS320C6711 DSK, of CCS version 1.23.
Could you please help me to solve the problem that I had mentioned in my 2nd message, the datasheet can be found in :
Next time do not spread questions all over the board, keep them in same post if they are related.
I merged topics into one post, next time you get a warning.
2nd February 2007, 13:17 #6
Newbie level 1
h bridge encoder
hi every body
i am using TMS320C6711 For controlling inverted pendulum. i want to know how can i get the PWM (Control signals) outputs from the DSK. please help in this case.
i will be very thankful to you.