Hey guys, I'm a little stuck trying to get a stepper motor to turn and was wondering of somebody could shed a bit of light on what may be going wrong...Just to close the net a little, I'll try to explain whats happening...
I have a c++ app communicating through a PIC18F, which controls a parallax propeller microprocessor with 4 DC motors (which is fine) and also communicates with five bs2 (basic stamp 2) processors through a 2 way data bus...which again is all fine.
Each stamp controls one stepper motor through a L293D h-bridge driver, and sends the required pulses and direction determined by the info sent down the bus.
Through development i've been using LED's to ensure the correct data is sent out of the driver which appears to work as expected, but now I've tried to replace said LED's with the steppers; when a instruction is sent (even a single pulse) the motor kind of clunks and shorts the circuit.
If you imagine each of the 5 drivers, connected to the five stamps has 4 led's connected to each, and each motor is controlled by a slider bar in the c++ app (the bigger the change in slider value, the longer the sequence). So if I send a sequence of pulses when the LED's are attached, each stamp operates independantly and simultainiously. Once I send a sequence to a stamp with the motor connected, all LED's go out.
The circuit doesn't stay shorted, it will except subsequent instructions, but again short once I try to communicate with the motored one!
I'm using a 20mm hybrid motor (http://www.motioncontrolproducts.com/pdfs/fl20-28.pdf) bought from a surplus net site, so i'm not too sure its totally cosure and I don't have any other motors to try out.
I've paired the wires by measureing the resistance between wires, and i've tried all other wiring possibilities to no avail
The other complication is that I'm using a 12v dc wall adapter to power my breadboard with a series of regulators providing the voltage levels required (3.3v; 5v; 8v; 12v + 5vusb) but i've had no difficulty running 4 12v dc motor simultainiously or any other power issues. I was thinking it could be a current issue, but I've disconnected pretty much everything, and I'm not sure that would short the circuit, just not move the motor...also there is a 100nf cap between both Vss and Vdd on each processor as well as each side of the regulator
I've just done a quick schematic of the pic -> stepper...I'd really appriciate some advice...if posting my code, a sketch or anything else may help i'll be right on it.
Sorry the post is so long, but I'd like to help as much as possible, and any advice or suggestions would be greatly appriciated
Cheers guys
Martyn
I have a c++ app communicating through a PIC18F, which controls a parallax propeller microprocessor with 4 DC motors (which is fine) and also communicates with five bs2 (basic stamp 2) processors through a 2 way data bus...which again is all fine.
Each stamp controls one stepper motor through a L293D h-bridge driver, and sends the required pulses and direction determined by the info sent down the bus.
Through development i've been using LED's to ensure the correct data is sent out of the driver which appears to work as expected, but now I've tried to replace said LED's with the steppers; when a instruction is sent (even a single pulse) the motor kind of clunks and shorts the circuit.
If you imagine each of the 5 drivers, connected to the five stamps has 4 led's connected to each, and each motor is controlled by a slider bar in the c++ app (the bigger the change in slider value, the longer the sequence). So if I send a sequence of pulses when the LED's are attached, each stamp operates independantly and simultainiously. Once I send a sequence to a stamp with the motor connected, all LED's go out.
The circuit doesn't stay shorted, it will except subsequent instructions, but again short once I try to communicate with the motored one!
I'm using a 20mm hybrid motor (http://www.motioncontrolproducts.com/pdfs/fl20-28.pdf) bought from a surplus net site, so i'm not too sure its totally cosure and I don't have any other motors to try out.
I've paired the wires by measureing the resistance between wires, and i've tried all other wiring possibilities to no avail
The other complication is that I'm using a 12v dc wall adapter to power my breadboard with a series of regulators providing the voltage levels required (3.3v; 5v; 8v; 12v + 5vusb) but i've had no difficulty running 4 12v dc motor simultainiously or any other power issues. I was thinking it could be a current issue, but I've disconnected pretty much everything, and I'm not sure that would short the circuit, just not move the motor...also there is a 100nf cap between both Vss and Vdd on each processor as well as each side of the regulator
I've just done a quick schematic of the pic -> stepper...I'd really appriciate some advice...if posting my code, a sketch or anything else may help i'll be right on it.
Sorry the post is so long, but I'd like to help as much as possible, and any advice or suggestions would be greatly appriciated
Cheers guys
Martyn
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