MCU TX should be connected to AD5700 RX pin. And MCU RX should be connected to AD5700 TX pin.
DUPLEX pin should also be set to low, so you should connect DUPLEX link option to pos B. Please let me know the results.
We use the EVAL-AD5700-1EBZ evaluation kit.
The DUPLEX connection option to position A. I have this answer:
The DUPLEX connection option to position B. I have this answer:
I looked at your connection diagram. And as Ivan mentioned above, the TX pin of the MCU should be connected to the RX pin of AD5700, while MCU RX should be connected to AD700 TX. Could you try that first, please, then let's check the result?
I am one of Loredana's colleagues and am working with her on the proiect.
The correct connections are TX-TX and RX-RX according to the official documents. Initially we used TX-RX and RX-TX, because this is was made sense, but after a day of debugging we figured out the names are switched on the AD5700 evaluation board.
See the attached image, taken from this document: https://www.analog.com/media/en/technical-documentation/data-sheets/AD5700_5700-1.pdf. It labels TXD as data input and RXD as data output.
The modulator's output is HART OUT and the demodulator input is HART IN, according to Figure 1 in the document.
If we connect TX-RX; RX-TX we get nothing on the UART lines. We sniff them with a couple of USB converters. However, if we use TX-TX and RX-RX the MCU receives UART messages and it responds to them.
The correct connections are TX-TX and RX-RX according to the official documents. Initially, we used TX-RX and RX-TX, because this is was made sense, but after a day of debugging we figured out the names are switched on the AD5700 evaluation board.