RS485 is electrical standard, from the LS1020A hardware point of view UART should be used to implement RS485.
RS485 half duplex means transmission and reception is performed over the same line (twisted pair). So, you have to manage RS485 line driver and explicitly switch it from reception to transmission. This is usually done in software, by using any GPIO pin. Also, in some types of UART, there is a support for "hardware flow control", so the transmitter can automatically assert hardware flow control line "request to send" (RTS) to start the transmission. There are two types of UART in LS1020A processor - DUART and LPUART. DUART does not support hardware flow control and requires GPIO to manage transmission direction. LPUART supports hardware flow control, so RTS may be used to control transmission direction.
Have a great day,
Alexander,
TIC
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RS485 is electrical standard, from the LS1020A hardware point of view UART should be used to implement RS485.
RS485 half duplex means transmission and reception is performed over the same line (twisted pair). So, you have to manage RS485 line driver and explicitly switch it from reception to transmission. This is usually done in software, by using any GPIO pin. Also, in some types of UART, there is a support for "hardware flow control", so the transmitter can automatically assert hardware flow control line "request to send" (RTS) to start the transmission. There are two types of UART in LS1020A processor - DUART and LPUART. DUART does not support hardware flow control and requires GPIO to manage transmission direction. LPUART supports hardware flow control, so RTS may be used to control transmission direction.
Have a great day,
Alexander,
TIC
-------------------------------------------------------------------------------
Note:
- If this post answers your question, please click the "Mark Correct" button. Thank you!
- We are following threads for 7 weeks after the last post, later replies are ignored
Please open a new thread and refer to the closed one, if you have a related question at a later point in time.
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No, we do not offer application note for LPUART in RS485 application.
Maximum baudrate is specified in device datasheet as fPLAT/(2 x 4) where fPLAT is platform clock.
However, it is said that "The actual attainable baud rate is limited by the latency of interrupt processing".
So, this means the maximum baudrate is limited by software.