UART Selection
2.3
UART Selection
The headers J1 through J6 have associated jumpers that connect two adjacent pins, such as pin 1 to 2 or
pin 2 to 3. This is to direct the UART signals from the CC256X EM to the desired STM32 board. Thus,
when the CC256XEM-STADAPT is mounted on the STM3240G-EVAL, all 6 jumpers should be connecting
pins 1 and 2. When mounted on the STM32F4DISCOVERY, the jumpers should be connecting pins 2 and
3.
Figure 2-2. Block Diagram of UART Connections
Table 2-6. UART Connections
STM32F4DISCOVERY
Connection
STM3240G-EVAL UART5
STM3240G-EVAL USART6
USART3
J1-J6
1 and 2
1 and 2
2 and 3
R60, R70, R80, R90
Connected
Unconnected
N/A
R61, R71, R81, R91
Unconnected
Connected
N/A
There are only two configurations – STM32F4DISCOVERY USART3 and STM3240G-EVAL USART6 –
necessary to run all of the demo programs that only require UART communication. In all of these, the
resistors R61, R71, R81, and R91 are always connected, while R60, R70, R80, and R90 are not.
However, the STM3240G-EVAL board provides the option of using UART5 for digital communication
instead of USART6. For these applications, the connections for the resistors must be swapped.
16
Hardware Description
SWRU417 – June 2015
Copyright © 2015, Texas Instruments Incorporated
