:shock: PWM with a dinasour pic :shock: atleast use a 16f628a or a 16f88 and get with the times the 16f84a went pre-historic about 5 years ago but the net still has heaps of projects based on them. For a H-bridge check out the sn754410 from texas instruments and look at a few robotic sites for tips as that chip is used quite a bit in robotic's.
Before you start messing a PIC, understand how to drive the stepper. It's not just energizing a motor's coil. there are several different kinds of steppers, each requiring differ drivemethods. read this tutorial first: https://www.cs.uiowa.edu/~jones/step/
:shock: PWM with a dinasour pic :shock: atleast use a 16f628a or a 16f88 and get with the times the 16f84a went pre-historic about 5 years ago .....
Cheers Bryan
:shock: PWM with a dinasour pic :shock: atleast use a 16f628a or a 16f88 and get with the times the 16f84a went pre-historic about 5 years ago .....
Cheers Bryan
Well you don't really need PWM with a stepper, nor an H-bridge, unless the stepper is the less common bi-polar type - for the more common uni-polar type you just need four transistors to drive the coils, or a ULN type chip. The PIC then generates the required step sequence, it's really VERY! easy to do.
well, actually, you can pwm unipolar or bipolar to limit the current and thus be able to drive the stepper at a higher voltage for more torque. The tutorial I linked to (Jones on Stepping Motors) discusses all these things.
well, actually, you can pwm unipolar or bipolar to limit the current and thus be able to drive the stepper at a higher voltage for more torque. The tutorial I linked to (Jones on Stepping Motors) discusses all these things.
resistors are an inefficient way to control current in steppers. For battery powered application, it wastes power. For larger steppers it generates heat and higher wattage resistors can be expensive. With a microcontroller, pwm is pretty simple.