Stepper Motor Control with Hercules High-End Timer - Part 2: Stepper Controller and MSP430 Firmware

RE: Stepper Motor Control with Hercules High-End Timer - Part 2: Stepper Controller and MSP430 Firmware

Jan Cumps — Sat, 03 Jun 2017 18:01:48 GMT

Pulse from 128 PPS to 512 PPS, accelerate rate 128 PPSPS

[View:/resized-image/__size/935x18/__key/commentfiles/f7d226abd59f475c9d224a79e3f0ec07-35917367-611e-4392-a691-603b3417f82b/5618.contentimage_5F00_188249.png:935:18]

Diagram of timestamp of each switch transition. From steep to almost linear (sample time of my analyser was exhausted before linearity was reached):

[View:/resized-image/__size/617x411/__key/commentfiles/f7d226abd59f475c9d224a79e3f0ec07-35917367-611e-4392-a691-603b3417f82b/1488.contentimage_5F00_188250.png:617:411]

Here is the diagram of the time between each transition. At ramp-up time the MSP430 sends pulses slower.

[View:/resized-image/__size/605x340/__key/commentfiles/f7d226abd59f475c9d224a79e3f0ec07-35917367-611e-4392-a691-603b3417f82b/5621.contentimage_5F00_188251.png:605:340]

3925

RE: Stepper Motor Control with Hercules High-End Timer - Part 2: Stepper Controller and MSP430 Firmware

Jan Cumps — Sat, 03 Jun 2017 17:26:52 GMT

Correlation between commands sent via SPI and register values read back from the driver:

[View:/resized-image/__size/1264x566/__key/commentfiles/f7d226abd59f475c9d224a79e3f0ec07-35917367-611e-4392-a691-603b3417f82b/contentimage_5F00_188248.png:1264:566]

RE: Stepper Motor Control with Hercules High-End Timer - Part 2: Stepper Controller and MSP430 Firmware

Jan Cumps — Sat, 03 Jun 2017 15:24:48 GMT

Some SPI captures for the next blog - initialising the driver.

A result from pressing the Set All button with below settings:

[View:/resized-image/__size/789x580/__key/commentfiles/f7d226abd59f475c9d224a79e3f0ec07-35917367-611e-4392-a691-603b3417f82b/8741.contentimage_5F00_188245.png:789:580]

Logic Analyzer capture:

[View:/resized-image/__size/790x91/__key/commentfiles/f7d226abd59f475c9d224a79e3f0ec07-35917367-611e-4392-a691-603b3417f82b/6607.contentimage_5F00_188246.png:790:91]

Protocol analysis:

[View:/resized-image/__size/790x745/__key/commentfiles/f7d226abd59f475c9d224a79e3f0ec07-35917367-611e-4392-a691-603b3417f82b/2477.contentimage_5F00_188247.png:790:745]

One of the things I noticed is that SPI chip select is active high ...

indexstart-timeend-timeevent?event-typeMOSI dataMISO data0-1,66??s-1,66??strueCS_LOW120,00?ns20,00?nsfalse3865220,00?ns20,00?nsfalse6553539,92??s9,92??strueCS_LOW412,24??s12,24??strueCS_HIGH513,68??s13,68??sfalse4282613,68??s13,68??sfalse65535723,82??s23,82??strueCS_LOW826,14??s26,14??strueCS_HIGH927,82??s27,82??sfalse82401027,82??s27,82??sfalse655351137,70??s37,70??strueCS_LOW1240,04??s40,04??strueCS_HIGH1341,46??s41,46??sfalse125521441,46??s41,46??sfalse655351551,60??s51,60??strueCS_LOW1653,94??s53,94??strueCS_HIGH1755,62??s55,62??sfalse171681855,62??s55,62??sfalse655351965,50??s65,50??strueCS_LOW2067,46??s67,46??strueCS_HIGH2168,76??s68,76??sfalse243842268,76??s68,76??sfalse655352378,64??s78,64??strueCS_LOW2481,54??s81,54??strueCS_HIGH2582,90??s82,90??sfalse246612682,90??s82,90??sfalse655352792,72??s92,72??strueCS_LOW2896,64??s96,64??strueCS_HIGH2998,06??s98,06??sfalse286723098,06??s98,06??sfalse6553531108,20??s108,20??strueCS_LOW

RE: Stepper Motor Control with Hercules High-End Timer - Part 2: Stepper Controller and MSP430 Firmware

Jan Cumps — Fri, 02 Jun 2017 14:12:05 GMT

video added

RE: Stepper Motor Control with Hercules High-End Timer - Part 2: Stepper Controller and MSP430 Firmware

DAB — Mon, 29 May 2017 18:25:34 GMT

Nice update Jan.

You have increased my interest. Maybe it would be useful for you to do some software breakout in a post and share some of the code and the issues you find difficult.

Maybe some of us can help you better understand the software in relations to the chip.

There could be some hidden gems within the chip and the code that we could all find useful.

DAB