What is the ARM_TXEV or "ARM tx event" interrupt?

[scottm]

Several NXP datasheets (for example, for the LPC55S69) reference "ARM tx event" or "ARM_TXEV" and say that it's an interrupt signal from the Cortex core. But the term is never defined, and ARM doesn't seem to use that terminology anywhere.

ALL Google hits on "ARM_TXEV" seem to come back to NXP documents, none of which provide any more information. It's used as an SCT input and as an ADC trigger, at least.

What is this signal in ARM terminology? Where does it come from and how is it used?

Scott

[xiangjun_rong]

Hi,

I suppose that the ARM Cortex-M4, Cortex-M33 and Cortex-M7 have a SEV instruction, which send an event signal to processor.

This is so-called ARM_TXEV instruction.

I will try the instruction later.

Hope it can help you

BR

XiangJun Rong

[scottm]

This was my best guess after more Googling. It's not critical to anything I'm doing right now, but it's one of those frustrating things that's just not explained anywhere in the documentation. I appreciate it when the hardware designers throw in features that might be useful but it's hard to make use of them when they don't get documented.

Thanks,

Scott

[xiangjun_rong]

Hi,

I have developed an example based on the lpadc_interrupt project, which can demo how to use ARM TX event to trigger ADC based on LPC55S69-EVK, SDK and MCUXpresso tools.

https://community.nxp.com/t5/LPC-Microcontrollers-Knowledge/example-to-use-ARM-TX-Event-to-trigger-A...

Hope it can help you

BR

XiangJun Rong

[scottm]

Cool, that's good to know. Are there side-effects to using the SEV instruction? It's going to generate a RX event on the other core, right?

Scott

[xiangjun_rong]

Hi,

I suppose there is side-effect to use the SEV instruction, the SEV instruction does not specify the receiver, it is a global signal, for example, it can wake-up the other core.

BR

XiangJun Rong