topic Need clarification on UART module name and clock enable method on S32K324/S32K344 in S32K

Need clarification on UART module name and clock enable method on S32K324/S32K344

minjaekang99 — Sat, 22 Nov 2025 09:21:33 GMT

Hello,

I am working with the S32K324 evaluation board and using the S32K344-based HSE Demo project (S32K3XX_demo_app).
I am trying to initialize UART, but the header file provided in the demo (S32K344.h) does not contain any UART-related definitions.

The following symbols do NOT exist in the header:
- LPUART1 / LPUART0~4
- PCC_LPUARTx
- LPUART_CTRL_*_MASK, LPUART_STAT_*_MASK
- Baud register macros (OSR/SBR)

In the Reference Manual (Table 263), I can only see entries like “Low Power UART0~4” under Partition 2 clock mapping,
but there is no information about the actual peripheral module name or register block associated with these UARTs.

**I need clarification on the following:**

1. What is the exact UART peripheral name used on S32K324/S32K344?
(Is it LPUART, LINFlexD, FLEXIO-UART, or something else?)

2. What is the correct base address and register structure for this UART module?

3. How should I properly enable the UART clock?
- Which MC_ME COFB REQ bit corresponds to UART?
- Or should the clock be enabled via PCC instead?

4. Which SIUL2 MSCR pins correspond to UART TX/RX, and what ALT/SSS value should be used?

The S32K344.h header in the demo project contains no UART definitions, so I am unsure which UART module to use or how to enable it.
Any guidance or an official reference to the correct UART module and registers would be appreciated.

Thank you.

Re: Need clarification on UART module name and clock enable method on S32K324/S32K344

minjaekang99 — Mon, 24 Nov 2025 08:03:34 GMT

Can anyone answer this question?

Re: Need clarification on UART module name and clock enable method on S32K324/S32K344

PetrS — Mon, 24 Nov 2025 08:40:46 GMT

Hi,

there are individual header files for each peripheral

1) IP_LPUART_x (IP_LPUART_0,...), IP_FLEXIO. See respective header files
2) This is specified in the device RM, in each peripheral chapter. Also check headers S32K344_LPUART.h, S32K344_FLEXIO.h etc
3) check Table 263. MC_ME partition peripheral mapping and clock control of the RM
4) not sure of the module do you refer to. It can be it is available on more pins. Refer to S32K344_IO Signal Table sheet of S32K344_IOMUX excel file attached to the RM. chapter 4
Signal Multiplexing describe how to work with IO signal table.

BR, Petr