UM0442

Hardware configuration and functionality

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Refer to Figure 14 and Table 9 for further details of the connector.

Figure 14.

DB9 male connector

4.15

UART connector

Other networking capabilities are offered by the UART connector on the board. It is linked to

the UART1 peripheral of the microcontroller through a ST202EC transceiver, using pins 11,

16 and 17 of the microcontroller itself, respectively for RTS, Tx and Rx capabilities.

The jumper JP19 near the transceiver, once closed, enables the CTS functionality. If open

the corresponding shared pin of the microcontroller (pin 15) can be used by the EXT

connector.

Before having a look at the pin correspondence Table 10 (the connector is a DB9 male as

the one used for CAN), a brief description of the S6 selector is needed.

If you close between the middle point and point 1 (upper side, near the connector), you

enable the RTS functionality, at the same time the jumper JP13 must be closed. Elsewhere,

if you close the middle pin with pin 3 you enable the NULL Modem mode (at the same time

jumper JP13 must be opened).

Table 9.

Pin numbering for the CAN connector

Pin number

Function

1NC

2NC

3GND

4CAN_L

5NC

6NC

7NC

8CAN_H

9GND