RE: Create and Measure signals with Hercules High End Timer (HET) - 1: adapt TI example to a LaunchPad

Jan Cumps — Wed, 08 Jan 2020 21:00:34 GMT

I found a bug in the application note example that caused the sampling part calculateand interrupt on wrong border conditions.

When I ported the code, I saw that the error sinal from the HET sampler failed with outside 17% - 41% ranges, instead of the expected 20 - 80%

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Turns out that the low resolution pre-scaler of the second het was taken from HALCoGen and never updated,while the one of HET1 is reprogrammed just before the HET engines are kicked off.

This caused that the 2nd het was only correct if the pre-scaler in the firmware was exactly the same as the one defined in HALCoGen for HET2.

I corrected the code so that HET2 uses the same pre-scaler as HET1. AS seen below, it now only shows the error output where the duty cycle is below 20 and above 80 %:

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RE: Create and Measure signals with Hercules High End Timer (HET) - 1: adapt TI example to a LaunchPad

Fred27 — Tue, 07 Jan 2020 18:33:11 GMT

An interesting read. TI do seen to like their quirky little side processors. There's the PRUs on the Sitara, the Sensor Controller in the CC26xx/CC13xx, and now the HET which I'd never heard of.

RE: Create and Measure signals with Hercules High End Timer (HET) - 1: adapt TI example to a LaunchPad

DAB — Mon, 06 Jan 2020 21:53:10 GMT

Nice update Jan.

DAB