L6470 and L6472 - What sets the speed of MOVE and GOTO operations? Using MAX_SPEED parameter imposes lower limit of 15.25 FS/sec and 15.25 FS/sec granularity.

[BMoul.1]

I want to use MOVE and GOTO on some of the steppers at less than 15.25 FS/sec and with finer control than 15.25 FS/sec increments. Is there a way to specify MOVE and GOTO speeds other than by using the MAX_SPEED setting?

[Dario CUCCHI · Accepted solution]

Hi @BMoul.1​ ,

to achieve such resolution, you should use the Step Clock mode.

In this case you can provide a clock signal on the STCK pin and precisely control the profiles of acceleration deceleration and speed.

Consider that using the step clock mode you have to implement the profile calculation in the external MCU generating the STCK signal.

In the L6472 datasheet or in the L6470 datasheet you can find the mode description in section 6.7.5 and the SPI command description in section 9.2.6.

Have a nice day !

[BMoul.1]

Thanks for the step clock suggestion. Will not be able to use it in the current embodiment but perhaps in the future.

Bill