Search results

Thanks. Managed to get past that and have an interrupt driven timer generating all time intervals. The program is working as expected. I wonder what the chance of doing some dsp filtering is? I have all the equations just need to write the code. I will try the code posting at some stage.

With a 12bit resolution, 4096 steps the pwm mark space ratio should be half this not 128 but 2048. I will keep experimenting... Wonder how the timers work??

I have come back to try and use the hardware pwm and some timers. First the PWM: It starts okay at 38khz on pin 4. However any attempt to change the MS ratio results in a totally wrong ratio. I have attached code and the scope display. Not sure how to get the sketch to display here??

Thank Paul, I have been working on the application today. It is just about working. On one of my sensors it is a bit slow to respond to the code. Took your advice a d bit banged. Just about enough adjustment in the counts to get the thing to work. The code is a bit expanded but it does allow me...

Wow! Now that is a lot of very useful information. Thanks Paul. Let me digest and learn. Back with some code soon..ish. My current scheme is heavily interrupt driven. It should make the timing flexible from a bunch of parameters. At the moment using pins 3 and 6 it almost feels as if the pwm...

Aprt from scrolling other code are there any docs on the peripherals or what the C code does to the Teensy?

Here is a shot of my current output. I will try in the morning the fast output instruction and some of the code you have uploaded. I will upload my code as well. Thanks for the help. I will be back soon.

My first post here. I need to sort out a data upload path. Tomorrow hopefully. My objective: Generate a group of 25 38khz bursts some of which are say 700us long with the same sort of gap and others are about 600us long with the same sort of gap. At the end of the 25 groups the signal goes quiet...

I am use to knowing what is going on behind the C code. Is there a compiler that is not as noddy as the Arduino pack? The 4.1 is a nice fast processor but the very slow operation of the compiler currently makes it pretty useless for me. As an example I am trying to modulate the output of the pwm...