Strato Pi CAN setup

• For the CAN bus, we use the built in 120Ω terminal resistor, activated by bridging jumper JP3.
• For the RS-485, we use the built in bias network of resistors, activated by bridging jumpers JP1, JP2 and JP4.

The watchdog of the Strato Pi has to be configured for our use. First the firmware has to be updated to 3.5. Then we can connect to the serial interface.

Where counting begins with the pin closest to the screw terminals as 1

The StratoPi uses the PIC MCU to toggle between receiving and transmitting on the half-duplex RS-485 connection. selecting the toggleing configuration is supposed to happen automatically, but for 115200baud, this happens too slow in cases where the receiving and transmitting switches instantaneously, producing garbage data. An example of this is the command mode of the TB Live hydrophone used.

To fix this, the StratoPi logic controller must be configured sending these commands over the 1200 8N1 setup serial:

XSMF // Set TX-Enable fixed speed mode
XSP98N1 // Set 115200 baud, 8N1
XCCS // Make configuration permanent