My first test was to send uint8 data from the Arduino and receive it on the Raspberry Pi. The “Outputs” pane contained the code to read from the open serial port. The “Discrete Update” pane contained initialization tasks such as opening the /dev/ttyAMA0 port for reading. Since I would be working with external C-libraries, I included them in the “Libraries” pane of the S-Function builder. Now that the hardware was ready, I set out to write the software part. I shorted the Tx and Rx pins on the Pi and ran minicom to see if it would print what was being typed on the keyboard. This library would give me access to C functions such as serialOpen() and fflush() needed for this task.īefore starting with the code, I wanted to test that the Rx pin was working. Gordon from GordonsProjects has a WiringPi library written in C that can be used on the Raspberry Pi. > system(mypi, ‘sudo rpi-serial-console disable’) > system(mypi, ‘rpi-serial-console status’) However, there is a more straightforward method through MATLAB by creating a raspi object connection to the Pi. You could do this manually through Putty by editing cmdline.txt and inittab as described here. In order to use this port on the Pi, the serial console needs to be disabled and then the system rebooted.

The serial port associated with the TX/RX pin is /dev/ttyAMA0. Writing the Serial Receive Driver for Raspberry Pi To set up the Arduino to transmit data, I pulled the Serial Transmit block from the Simulink Library and connected a constant block set to emit uint8 values. R2 = input(‘What is resistor value R2 (Ohms)?: ‘, ‘s’) ĭisplay(R1, ‘Value of R1’) Voltage Divider Circuit

Rather than spend time calculating different values on paper, I wrote a MATLAB script that would do the job. With a limited number of resistors at my disposal, I had to calculate a combination of resistors that would do the trick. The voltage at the TX/RX pins for the Pi (3.3V) and Arduino (5V) are different, so I set up a voltage divider circuit to scale the voltages appropriately. Hardware Note – Connecting the Pi and Arduino

Arduino mega serial port not found