AWR2243: HostIRQ when communicating over I2C

Tim Teuber

Part Number: AWR2243
Other Parts Discussed in Thread: DCA1000EVM,

Hi Team,

In a previous conversation I had in this forum, it was suggested, that when using I2C instead of SPI, the HostIRQ connection between Host MCU and awr2243 is not needed. In another Post on this forum, it is suggested that the connection is indeed needed for proper I2C communication. Can you tell me whats the truth?

Check for reference:

https://e2e.ti.com/support/sensors-group/sensors/f/sensors-forum/1314638/awr2243-questions-about-hostirq-when-using-i2c-instead-of-spi?tisearch=e2e-sitesearch&keymatch=awr2243%252520tim%252520teuber#

https://e2e.ti.com/support/sensors-group/sensors/f/sensors-forum/1032451/awr2243-question-about-sop-7-i2c-mode-of-operation

Best regards,

Tim

over 1 year ago

0 Josh Wyatt over 1 year ago

TI__Guru* 91206 points

Tim -

Looks like using/servicing the IRQ is required for the overall operation to be successful, as in this case an IRQ is needed outside of the I2C protocol, so the controller can get the data from the device over I2C. (As you may already know, I2C has no mechanism for target device to indicate to controller that data is ready - the second thread you linked to has a critical detail as well, on how to service the IRQ correctly, towards the end of the thread.

0 Tim Teuber over 1 year ago in reply to Josh Wyatt

Intellectual 390 points

Thanks Josh.

I was already assuming this. Does mmwave link take care of the CNYS Pattern, or do I have to self implement this in my porting?

Furthermore, could you explain the porting of the rlRegisterInterruptHandler Function? I cant find details about this in the porting guide. Does this Function check the HostIRQ?

0 Josh Wyatt over 1 year ago in reply to Tim Teuber

TI__Guru* 91206 points

Tim -

From the other two posts you found - yes that is exactly how it works, but from first one, you need to follow those instructions to switch from SPI to I2C

and from second

0 Tim Teuber over 1 year ago in reply to Josh Wyatt

Intellectual 390 points

Thank you,

Just for confirmation: When im writing my own porting, not based on the given examples, communicating in I2C only requires booting with SOP=7 and implementation of the Communication Functions / Device Control Functions? Or are there any registers/variables that have to be set?

0 Josh Wyatt over 1 year ago in reply to Tim Teuber

TI__Guru* 91206 points

Tim -

You can confirm these settings:

Using mmwavelink you can interface embedded MCU over I2C with AWR2243 device.

If you follow C:\ti\mmwave_dfp_02_02_03_01\ti\example\mmWaveLink_SingleChip_Example, there is showcases the I2C communication flow as well.

You just need to change & implement the communication callbacks that matches with your embedded MCU.

clientCtx.comIfCb.rlComIfOpen = rlsCommOpen;
clientCtx.comIfCb.rlComIfClose = rlsCommClose;
clientCtx.comIfCb.rlComIfRead = rlsI2cRead;
clientCtx.comIfCb.rlComIfWrite = rlsI2cWrite;

This example uses FTDI chip (resided on DCA1000EVM or mmWave DevPack) for I2C interface with AWR2243BOOST EVM.

You can refer C:\ti\mmwave_studio_03_00_00_14\mmWaveStudio\ReferenceCode\FTDILib\SourceCode for rlsI2cRead/Write function implementation for your development.

Refer these threads for I2C connection setup (HW)

https://e2e.ti.com/support/sensors-group/sensors/f/sensors-forum/927518/awr2243-awr2243-gpio-i2c-address

https://e2e.ti.com/support/sensors-group/sensors/f/sensors-forum/958428/awr2243-4-pcs-awr2243-cascaded-fpga-use-one-i2c-and-one-spi-to-connect-4-pcs-awr2243-4-pcs-awr2243-have-different-i2c-device-address-gpio-set-spi-clk-mosi-miso-of-4-pcs-2243-connect-together/3543303#3543303

from this post, where user was leveraging existing HW and got this to work.

https://e2e.ti.com/support/sensors-group/sensors/f/sensors-forum/1028818/awr2243-awr2243-not-working-in-i2c-functional-mode-sop7

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AWR2243: HostIRQ when communicating over I2C