I am trying to achieve stepper speeds between 1 and 100 mm/hour using the BlackBox 32 and a nema23 stepper motor. I contacted open builds and they suggested I may be able to achieve this using custom firmware. Looking on the grbl git I see the grbl firmware for an Arduino Uno. In the config.h file there are some definitions that look like they would allow me to enter speeds slower than the current minimum of 1mm/min. Referring to the #define N_DECIMAL_RATEVALUE_MM which is normally set to 0. I think I can set this to 4, enter my desired speed, and be off to the... races... so to speak. Now I'm looking for the grbl firmware for the BlackBox 32. I think I found it here but was hoping someone could a) confirm that this is where I get the most recent firmware for the BlackBox X32, and b) confirm my idea for changing the minimum speed and/or point me in the right direction for reducing the minimum speed limitation for the stepper motors.
Nope, check the date on the repo, thats our old grbl custom images. grblHAL: grblHAL is where you'll find the firmware used for the X32, our pinmap is in the ESP32 repo ESP32/BlackBoxX32_map.h at master · grblHAL/ESP32 and also available in grblHAL Web Builder: http://svn.io-engineering.com:8080/?driver=ESP32&board=BlackBox X32 If you look over the older grbl issues for example 0.9i - Min feedrate appears to be around 40-45mm/min · Issue #742 · grbl/grbl - there was indeed a minimum speed. That is quite slow, you may need to just us an arduino and a DQ542MA and calculate how far aparts pulses should be and let it slowly pulse the step input.
Thank you Peter van der Walt. I decided to try the custom firmware route today before switching to Arduino and DQ542MA. I was able to build the version of the firmware in the GitHub - grblHAL/ESP32: grblHAL driver for ESP32 repo but when I flash it to the controller I get repeated errors seen below: Any thoughts on what may have caused this? Only thing I changed was the MINIMUM_FEED_RATE 0.001f in the config.h file.
We already run grblHAL Reboot loop is indicative of something wrong in your firmware setup , to recover flash our standard grblHAL from wizards and tools > Firmware flashing tool > X32 > 3 Axes (might need to use the Erase Settings option for a fresh start over) Rebuilding grblHAL won't really change the outcome of the minimum step rate and certainly does not count as custom firmware as I meant it You can test if the limitation still exists (in theory it should): Issue a move command with the slow feedrate you are interested in and see how it goes. If grblHAL/grbl can't go that slow, you need proper custom firmware (BlackBox X32 has an ESP32, so you can write arduino firmware on that too - just outside scope of tech support)
II was able to recover using the wizard but I would still like to adjust the MINIMUM_FEED_RATE to 0.001f in the config.h file. Is there some way to do this without rebuilding the grblHAL project? Is there some obvious setup step that I may be missing when building the project?
Not sure what you are missing, but Min Feedrate is not always limited by a config, but by timer resolution and frequency. The reboots might be because setting it too low messes with timers in ways that it can't handle All theory of course, that level of discussion should be directed at the grblHAL repo > Issues
