XMC1302 UART Pin Selection

[User19677]

Reading the datasheet for the XMC1302 I thought I could use U0C0 for UART on the following pins.
p0.14 -> ALT6 -> U0C0.DOUT0 -> TX
p0.15 -> -> U0C0.DX0B -> RX

However, this did not work - no serial data. Confirmed with serial adapter and scope.

So, I used the DAVE pin configuration tool to see what pins are recommended for UART, and to my surprise, p014 and p015 are not indicated.

To complete the investigation, I selected P0.6 and p0.7 since they are indicated for UART use by DAVE. These pins worked - serial data received.

Where in the datasheet can I find an explanation as to why I cannot use pins p.014 and p.015 or UART?

Thanks.

[jferreira]

Hi,

P0.14/P0.15 are used as SWDCLK/SWDIO for debugging if the BMI is configured as SWD0.
See https://www.infineon.com/dgdl/Infineon-ApplicationNote_XMC1000_Microcontroller_BootModeHandling-AN-v... for more details.
You can read the current BMI using the JLink commander command get_bmi.

In DAVE4, the CPU_CTRL_XMC1 reserves the usage of the pins for debugging so that no other APP tries to allocate them.



Regards,
Jesus

[User19677]

Perfect. Thank you, Jesus for the information. I will read up on the BMI.