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Rev. 1.00
498 of 576
January 28, 2022
32-Bit Arm
®
Cortex
®
-M0+ MCU
HT32F54231/HT32F54241/HT32F54243/HT32F54253
23 Universal
Asynchronous Receiver T
ransmitter (UART)
PDMA Interface (HT32F54243/HT32F54253 only)
The PDMA interface is integrated in the UART. The PDMA function can be enabled by setting
the TXDMAEN or RXDMAEN bit in the URCR register to 1 in the transmit or receive mode
respectively. When the UART transmit data register (TDR) is empty and the TXDMAEN bit is
set to 1, the PDMA function will be activated to move data from a source location into the UART
transmit data register (TDR).
Similarly, when the received data has been in the UART receive data register (RDR) and the
RXDMAEN bit is set to 1, the PDMA function will be activated to move data from the UART
receive data register (RDR) to a specific destination location. For a more detailed description about
the PDMA configurations, refer to the PDMA chapter.
Register Map
The following table shows the UART registers and reset values. The PDMA related describes are
only available for the HT32F54243/HT32F54253 devices.
Table 61. UART Register Map
Register
Offset
Description
Reset Value
URDR
0x000
UART Data Register
0x0000_0000
URCR
0x004
UART Control Register
0x0000_0000
URIER
0x00C
UART Interrupt Enable Register
0x0000_0000
URSIFR
0x010
UART Status & Interrupt Flag Register
0x0000_0180
URDLR
0x024
UART Divider Latch Register
0x0000_0010
URTSTR
0x028
UART Test Register
0x0000_0000