From RS485 to RS232

I need convert a signal RS485 full duplex in RS232.
Does anyone know the more easy way?

I tried a commercial converter but it was for half duplex only…

Maybe an overkill solution (Arduino DUE):

Program USART0 (Serial1) in RS485 Full Duplex mode. Use Serial2 (USART1) in RS232 mode, and send via Serial2 the received data from Serial1. And vice versa.

Does anyone know the more easy way?

Easier than what? Have you tried a MAX490/MAX232 combination?

ard_newbie:
Maybe an overkill solution (Arduino DUE):

Program USART0 (Serial1) in RS485 Full Duplex mode. Use Serial2 (USART1) in RS232 mode, and send via Serial2 the received data from Serial1. And vice versa.

Please define what modes you mean by "RS485 Full Duplex mode" of USART0 or "RS232 mode" of USART1. The datasheet has no modes of this name and I cannot find any information about RS485 or RS232 drivers built into this chip.

See page 769

35.1 Description
The Universal Synchronous Asynchronous Receiver Transceiver (USART) provides one full duplex universal synchronous asynchronous serial link.

See page 772

Figure 35-2. Application Block Diagram

See page 801

35.7.6 RS485 Mode
The USART features the RS485 mode to enable line driver control. While operating in RS485 mode, the USART behaves as though in asynchronous or synchronous mode and configuration of all the parameters is possible

See page 769

35.1 Description
The Universal Synchronous Asynchronous Receiver Transceiver (USART) provides one full duplex universal synchronous asynchronous serial link.

I should re-download datasheets more often, it seems. In my old version the mode is not called RS-485 mode.

The described mode is to simplify the signaling of a half-duplex (not full-duplex as requested by the OP) RS485 driver (as p.e. the MAX485), it does not provide an RS485 signal itself. The same is true for RS232, the output is not an RS232 signal but just the necessary signals for an appropriate driver (p.e. MAX232).

Of course you need an RS 485 transceiver.

pylon:
I should re-download datasheets more often, it seems. In my old version the mode is not called RS-485 mode.

The described mode is to simplify the signaling of a half-duplex (not full-duplex as requested by the OP) RS485 driver (as p.e. the MAX485), it does not provide an RS485 signal itself. The same is true for RS232, the output is not an RS232 signal but just the necessary signals for an appropriate driver (p.e. MAX232).

If you read it on the internet, it must be true.

I have not physically used RS-485, but my understanding is it uses two wires. To send data the bits are sent by switching the wires +, -, for each bit. A ground wire is not involved. Full duplex is not physically possible.

I worked for years with RS-232. It does the same polarity switching between a transmit wire and a ground or common wire. That leaves a third wire, which can be transmitting at the same time. That is how the "break" is sent to the transmitter to cause it to stop. It also has caused grief when a response is sent to a message before the transmitter is through sending. So, full duplex on RS-232, yes. On RS-485, no.

Paul

+1

How about this

If you read it on the internet, it must be true.

If you've never seen it in the past, it must not exist.

I have not physically used RS-485, but my understanding is it uses two wires. To send data the bits are sent by switching the wires +, -, for each bit. A ground wire is not involved. Full duplex is not physically possible.

Full duplex RS485 uses 4 wires. Full duplex RS485 is not very common but as there are plenty of drivers for it there must be some uses out there.

I worked for years with RS-232. It does the same polarity switching between a transmit wire and a ground or common wire. That leaves a third wire, which can be transmitting at the same time. That is how the "break" is sent to the transmitter to cause it to stop. It also has caused grief when a response is sent to a message before the transmitter is through sending. So, full duplex on RS-232, yes. On RS-485, no.

This is not true as I expressed above, full duplex RS485 simply uses 4 wires, one pair for each direction.