Stepper Motor Control with Hercules High-End Timer - Part 5: Hercules RM57 Hardware Provisioning

RE: Stepper Motor Control with Hercules High-End Timer - Part 5: Hercules RM57 Hardware Provisioning

Jan Cumps — Fri, 09 Jun 2017 14:56:49 GMT

I have SPI working on the Hercules.

This is a capture of the same init sequence I captured earlier on on the MSP430:

[View:/resized-image/__size/620x69/__key/commentfiles/f7d226abd59f475c9d224a79e3f0ec07-8292d524-b67d-4849-816b-4fd37c5d5991/contentimage_5F00_184684.png:620:69]

Protocol Analysis:

[View:/resized-image/__size/618x709/__key/commentfiles/f7d226abd59f475c9d224a79e3f0ec07-8292d524-b67d-4849-816b-4fd37c5d5991/contentimage_5F00_184685.png:618:709]

Easiest job done. Now the high-end timer ...

RE: Stepper Motor Control with Hercules High-End Timer - Part 5: Hercules RM57 Hardware Provisioning

Jan Cumps — Fri, 09 Jun 2017 10:54:28 GMT

It seems that I can't turn the ADC pin that's connected to nSLEEP as a GIO output. Except for the ADC event pin, the module isn't configurable as GIO.

External event pin (ADEVT) programmable as general-purpose I/O

That means that I'll have to hack the BoosterPack. The pin above the ADC is a GIO.

[View:/resized-image/__size/364x289/__key/commentfiles/f7d226abd59f475c9d224a79e3f0ec07-8292d524-b67d-4849-816b-4fd37c5d5991/contentimage_5F00_184682.png:364:289]

I've just double-checked with a meter that it isn't connected to anything.

So I can put a bridge between J1 PIN 5 and 6 on the BoosterPack.

Then I can drive the GIO pin high or low as needed. The ADC pin won't mind. It can have 3V3 without issues.

I'll use a male pin header and hack that onto the connector pins. I can then use a jumper to make and break.

RE: Stepper Motor Control with Hercules High-End Timer - Part 5: Hercules RM57 Hardware Provisioning

Jan Cumps — Mon, 05 Jun 2017 14:50:57 GMT

SPI chip select (active high !)

It should be possible to use a positive chip select with this functionality:

[View:/resized-image/__size/651x282/__key/commentfiles/f7d226abd59f475c9d224a79e3f0ec07-8292d524-b67d-4849-816b-4fd37c5d5991/contentimage_5F00_184681.png:651:282]

I can set exactly what CS pin of SPI3 is high or low during activation of transfer. Looks good...

Correction: the CS is on GIOB pin 2. So I'll have to manually CS. No problem