DAC8742HEVM: Sending data via UART IN pin on DAC8742HEVM

Ibrahim,

How is this different than your other post? For reference, see the link below.

https://e2e.ti.com/support/data-converters-group/data-converters/f/data-converters-forum/1342993/dac8742h-uart-communication-in-dac8742hevm

In that setup, the GUI send the UART_IN signal, it translates it to the PAFF signal and then the GUI receives it on UART_OUT. Are you sending a different UART_IN signal?

If you're trying to duplicate this, maybe start by duplicating the settings and the data. I don't think you would need the FULL DUPLEX setting again, but just in case, click that. Then duplicate the data. Send what I sent on the last post of 0x91 0x00 0xAE 0x05 0x07, and then generate the read for two bytes. This is how it was set the last time.

I would imagine that would work as long as the EVM board is configured the way it was configured in the last post.

Joseph Wu

Dear Joseph,

Thank you for your response.

Correct, last time I try send PAFF UART data on the GUI Software. Now I still can send and receive the data on GUI.

But when I try to send that data 0xEA 0x91 0x00 0xAE 0x05 0x07 through UART_IN pin (not via DAC8742 GUI Software), I didn't receive the data.

I use USB to serial converter on my PC to send the data.

Here is wiring configuration:

Green ==> GND to GND pin USB Serial converter

Orange ==> UART_IN to TX pin USB Serial converter

Blue ==> UART_OUT to RX pin USB Serial converter

I send the same UART data through UART_IN pin via HTerm software (Baudrate 57600, 8N1).

After I send the data via HTerm software (not via click "Generate Write" button on DAC8742 GUI software) and I try to receive the data by click the "Generate Read" button on DAC8742 GUI Software, I didn't get anything.

Could you give me some advise about this?

Thank you for your support.

Regards,

Ibrahim

Ibrahim,

The UARTIN is still connected to an output from the USB2ANY, and there may be contention from the output of your terminal program to the output of the USB2ANY. Have you tried using an oscilloscope to check the UARTIN signal getting to the device? I would expect the contention between these outputs to cause signal disruptions, and your UART signal may not make it to the device.

Joseph Wu

Dear Joseph,

Yes I think you're correct. There is some contention between these outputs (USB2ANY and USB to Serial) and cause signal disruptions. 

Here's the signal when I try send the data via GUI.

Here's the signal USB to Serial TX pin output (Not connected to DAC8742H EVM).

Here's the signal when I connect USB to Serial to DAC8742H EVM and USB2 ANY is still connected (no signal).

Do you think I need to try DAC8742H EVM without USB2ANY?

Thank you for your support.

Regards,

Ibrahim

Dear Joseph,

Thank you for your support, I can send and receive some data on DAC8742H EVM trough USB to Serial.

Do you have any reference for Foundation Fieldbus (FF) H1 protocol frame data format?

Thank you.

Regards,

Ibrahim