Reduced Stepper Rate

[amctgt]

I need to use grblHAL on a BlackBox X32 to control the motion of a workpiece. My process requires very slow movement rates on the order of 1mm/hour. I attempted to edit the config file to reduce the MINIMUM_FEED_RATE from 1.0f to 0.001f. I then changed the cMakeLists.txt file so that "OPTION(BOARD_BLACKBOX_X32 "Compile for BlackBox X32" ON)" was "ON", rebuilt the project and flashed it to my BlackBox X32. When I reset it, I get a repeated error It eventually says "ok" then I can send a move command, it will execute but then return "ok" several times followed by the "GrblHAL 1.1f ['$' or '$HELP' for help]" error code several times. My two main questions are:

1. How can I rebuild the code without causing all of these errors?
2. Is this the best way to go about reducing the minimum speed?

I am running Windows 11 and using Eclipse IDE for Embedded C/C++ Developers (includes Incubating components) Version: 2021-09 (4.21.0) Build id: 20210910-1417 and built and flashed using ESP-IDF 4.4 command prompt.

[terjeio]

1. By using ESP-IDF v4.3? I have no idea what might cause the repeated messages except perhaps some breaking changes in the IDF framework. Try this binary:

app-template.zip

2. Minimum feedrate is also capped by code in driver.c. This has to be changed as well - taking into account your step/mm setting as the capping was added to get rid of some, seemingly random, very long step intervals. Note that the attached binary has the cap removed.

[amctgt]

Hi Terjeio, thank you for your response! I was not using the ESP-IDF c4.3 I tried using the latest version. I downloaded v4.3 and was able to compile and flash without the errors I was previously encountering.

For that binary file, I uploaded it via the openbuilds firmware flashing wizard and it is working at the desired low rates, thank you! I am curious, what exactly did you change to remove the cap?

[terjeio]

what exactly did you change to remove the cap?

TIMERG0.hw_timer[STEP_TIMER_INDEX].alarm_low = cycles_per_tick;