Debug Serial Back Channel Connection¶

A secondary serial debug connection exists in the TI-OpenThread examples. This section will describe the physical connections needed to take advantage of the default pin mapping for this back channel.

Note

The LaunchPad VDD-IO is 3.3V, not 5V, be careful with your connections.

Multiple flying lead USB-to-Serial adaptors exist, such as:

Fixed header USB-to-Serial can also be used with jumper wires, like:

FTDI TTL-232R-3V3

Or the UART back-channel on a second LaunchPad could be used by jumpering the TXD and RXD headers.

An example setup with the USB to TTL Serial Cable can be seen in Figure 90.

../_images/fig-debug-uart-connections.jpg

Figure 90. USB to TTL Serial Cable connections to the CC13xx or CC26xx LaunchPad¶

The default routing for the CC13xx or CC26xx LaunchPad are connections are board TX is DIO18 and board RX is DIO19. The corresponding connections for the USB to TTL Serial Cable are as follows:

Color	Connection	Pin
Green	Transmit from USB	`DIO19`
White	Receive from USB	`DIO18`
Black	Ground	`GND`
Red	VCC	No Connect

Warning

Consult the datasheet for your USB-to-Serial connection before powering the device.