AM5718: why connect pin AB9 to UART2_TXD

Tony Tang

Part Number: AM5718

In the AM5718 IDK schematic, why connect AB9 to RS-485 UART2_TXD? if just for RS-485 usage, can leave AB9 unconnected?

0 Robert Eschler over 4 years ago

I've requested for input from individuals involved in the design. My guess its related to the PRU function - but lets see what experts respond.

0 Tony Tang over 4 years ago in reply to Robert Eschler

Robert,

Please help to response.

0 Robert Eschler over 4 years ago in reply to Tony Tang

Feedback is AB9 is used for TX detect to control the logic on DE/ RE# of the RS485 transceiver.

0 Tony Tang over 4 years ago in reply to Robert Eschler

Robert,

Thanks.

#1. What pinmux of AB9 in this usecase? PRU pin?

#2. Is it also needed for customer design? as usually RX485 doesn't connect in this way.

#3. And if it related with Processor SDK Linux driver? if customer doesn't connect AB9, does he need to modify driver?

0 Robert Eschler over 4 years ago in reply to Tony Tang

Answered in previous E2E post:

Processors forum