Search found 780 matches

by OutoftheBOTS_
Wed Jan 08, 2020 7:11 am
Forum: Programs, Libraries and Tools
Topic: Multiaxis stepper motors using RMT
Replies: 32
Views: 2225

Re: Multiaxis stepper motors using RMT

DRV8825 Stepper Motor Controler IC allow a max step frequency of 250 kHz and up to 1/32 microstepping. Min Pulse duration, STEP high and STEP low is 1.9 µs. So I'm trying to drive this IC to its maximum, in case I need to use 1/32 microstepping resolution and speed. Even if I'm close to reach 250 k...
by OutoftheBOTS_
Sat Jan 04, 2020 9:15 pm
Forum: Programs, Libraries and Tools
Topic: Multiaxis stepper motors using RMT
Replies: 32
Views: 2225

Re: Multiaxis stepper motors using RMT

Just wondering why your chasing 250KHz?? many of the cheaper motion controllers only do about 50KHz and work quite well.
by OutoftheBOTS_
Fri Jan 03, 2020 8:29 am
Forum: Other Boards
Topic: New STM32H743VIT6 dev boards
Replies: 32
Views: 3113

Re: New STM32H743VIT6 dev boards

I haven’t worked with H7’s before. If there are other H7 boards running MicroPython, should be pretty easy to make a board def for it. Just need to know which pins they map to the peripherals. If you are unable to get the schematics pdf from the seller, let me know and I’ll see if I can find it on ...
by OutoftheBOTS_
Wed Jan 01, 2020 8:26 pm
Forum: Programs, Libraries and Tools
Topic: Multiaxis stepper motors using RMT
Replies: 32
Views: 2225

Re: Multiaxis stepper motors using RMT

The longest pulse is 32768 time units. Using a clock prescaler of 80 this is 32768 ms. 100000 % 32868 is about 1700, and that is what you got. This really means we need a way to preload (buffer) the next list of pulses to be loaded to RMT. I assume this feature will be needed to be added at the C l...
by OutoftheBOTS_
Wed Jan 01, 2020 11:54 am
Forum: Programs, Libraries and Tools
Topic: Multiaxis stepper motors using RMT
Replies: 32
Views: 2225

Re: Multiaxis stepper motors using RMT

I'd definitely consider ways to improve RMT to support continuous tx... Another smaller but harder question, can an odometer be added so that every time the RMT sends a step pulse it increments a counter?? Yes, I suppose that would be possible; what are you thinking? First thanks for working on the...
by OutoftheBOTS_
Wed Jan 01, 2020 8:48 am
Forum: Other Boards
Topic: New STM32H743VIT6 dev boards
Replies: 32
Views: 3113

New STM32H743VIT6 dev boards

I just saw these very well priced STM32H743VIT6 dev boards from the manufacturer that I usually buy me STM32F407VIT6 boards from https://www.aliexpress.com/item/4000300005466.html?spm=a2g0o.detail.1000014.37.1ab84550aFjlrP&gps-id=pcDetailBottomMoreOtherSeller&scm=1007.13338.128125.0&scm_id=1007.1333...
by OutoftheBOTS_
Wed Jan 01, 2020 7:22 am
Forum: Programs, Libraries and Tools
Topic: Multiaxis stepper motors using RMT
Replies: 32
Views: 2225

Re: Multiaxis stepper motors using RMT

Wow this is super interesting to me. I thought you might like RMT. ;) I play with steppers for many of my robotics projects. I having mainly found MP problematic for stepper pulse generation especially for multiple steppers so for many of my project I have had to use C and timers for interrupts to ...
by OutoftheBOTS_
Tue Dec 31, 2019 6:31 am
Forum: Programs, Libraries and Tools
Topic: Multiaxis stepper motors using RMT
Replies: 32
Views: 2225

Re: Multiaxis stepper motors using RMT

Wow this is super interesting to me. I play with steppers for many of my robotics projects. I having mainly found MP problematic for stepper pulse generation especially for multiple steppers so for many of my project I have had to use C and timers for interrupts to generate the step pulses. I have ...
by OutoftheBOTS_
Mon Dec 30, 2019 8:00 pm
Forum: General Discussion and Questions
Topic: Pulse counter without interrupts
Replies: 2
Views: 339

Re: Pulse counter without interrupts

You will need to read the reference manual for the MCU that your using and see what registers you need to set. I have done this in C on STM32F103 but would be very similar on the MCU that your using. Iused it to read the Quadrature encoders on a motor and did the same thing as u read the count perio...
by OutoftheBOTS_
Mon Dec 23, 2019 5:56 am
Forum: Announcements and News
Topic: MicroPython version 1.12 released
Replies: 19
Views: 6950

Re: MicroPython version 1.12 released

MP continues to march forward.

A big Thanks to all the contributors. :)