1.9 FLEXCOM RS485
This example application shows how to use the FLEXCOM module in RS485 mode.
Description
This example connects two boards through the RS485 interface.
One board acts as the transmitter, and the other acts as the receiver.
Downloading and Building the Application
To clone or download this application from Github, go to the main page of this repository and then click Clone button to clone this repository or download as zip file. This content can also be downloaded using content manager by following these instructions.
Path of the application within the repository is apps/flexcom/usart/flexcom_rs485.
To build the application, refer to the following table and open the project using its IDE.
| Project Name | Description |
|---|---|
| sam_a7d65_curiosity.X | MPLABX project for SAMA7D65 Curiosity Board |
| sam_a7d65_curiosity_pro.X | MPLABX project for SAMA7D65 Curiosity Pro Board |
Setting Up AT91Bootstrap Loader
To load the application binary onto the target device, we need to use at91bootstrap loader. Refer to the at91bootstrap loader documentation for details on how to configure, build and run bootstrap loader project and use it to bootstrap the application binaries.
Setting Up the Hardware
The following table shows the target hardware for the application projects.
| Project Name | Description |
|---|---|
| sam_a7d65_curiosity.X | SAMA7D65 Curiosity Board |
| sam_a7d65_curiosity_pro.X | SAMA7D65 Curiosity Pro Board |
Setting Up SAMA7D65 Curiosity Development Board
- Connect SmartCard Xplained Pro to Mikrobus1 header
- Insert AT88SC1616C SmartCard into SmartCard Xplained Pro socket
- Connect the Debug USB port on the board to the computer using a micro USB cable
- Connect the USB port J3 on board to the computer using a micro USB cable (to power the board)
- The hardware setup requires two boards, one acting as the Host and the other as the Client
- Connect the RS485-XPRO to the mikroBUS socket on the board using wires,
following the table below
ATRS485 J100 mikroBUS 1 SAMA7D65 UART_TX IO0 14 COPI PA18 FLEX4_IO0 UART_RX IO1 13 CIPO PA17 FLEX4_IO1 UART RTS IO4 5 CS PA14 FLEX4_IO4 3.3V 20 3.3V 3.3V GND 2 or 19 GND GND
Setting Up SAMA7D65 Curiosity Pro Development Board
- Connect SmartCard Xplained Pro to mikroBUS 1 header
- Insert AT88SC1616C SmartCard into SmartCard Xplained Pro socket
- Connect the Debug USB port on the board to the computer using a micro USB cable
- Connect the USB port J1 on board to the computer using a micro USB cable (to power the board)
- The hardware setup requires two boards, one acting as the Host and the other as the Client
- Connect the RS485-XPRO to
the mikroBUS socket on the board using wires, following the table
below
ATRS485 J100 mikroBUS 1 SAMA7D65 UART_TX IO0 14 COPI PA18 FLEX4_IO0 UART_RX IO1 13 CIPO PA17 FLEX4_IO1 UART RTS IO4 5 CS PA14 FLEX4_IO4 3.3V 20 3.3V 3.3V GND 2 or 19 GND GND
Running the Application
- Open the Terminal application (Ex.: Tera term) on the computer.
- Connect to the USB Serial COM
port and configure the serial settings as follows:
- Baud: 115200
- Data: 8 Bits
- Parity: None
- Stop: 1 Bit
- Flow Control: None
- Build and Program the application using its IDE.
- One board acts as the
transmitter, and the other acts as the receiver.
This is defined by the user.