topic LPC865M201JHI48 - UART polling method Driver in LPC Microcontrollers

LPC865M201JHI48 - UART polling method Driver

BerlinRaj — Thu, 16 May 2024 04:42:34 GMT

hello, I wants to configure uart in the LPC865M201JHI48 Customized board and i copied the lpc865 SDK driver Example to my customized board. I tried using the usart_polling.c example and although the transmission of data seems to be working, there seems to be a problem for its transmitting garbage values.

note: Lpc865 SDK example Driver belongs to lpc865m201jbd64

I am using REAL TERM Serial Terminal which I configured to 9600 baudrate, 8 data bits, 1 stop bit, no parity and no flow control.its transmitting some garbage value and real term serial teminal status indicating BREAK. what should i do?

If you have any ideas or solutions, I would gladly welcome any help.

Thanks in advance.

I have attached the usart_polling.c to the message.

Re: LPC865M201JHI48 - UART polling method Driver

xiangjun_rong — Thu, 16 May 2024 09:12:21 GMT

Hi,

Regarding your question, in the application code, the internal FRO is used as the driving clock of uart, because the internal FRO is not accurate, in other words, which leads to the mismatch with the receiver of uart, so sometimes, garbage byte is possible. The main_clk is from internal FRO.

You use customized board, do you connect external clock source to CLKIN pin or external crystal(Xtalin/Xtalout pins)? if you have external clock source or crystal, pls try to use the external clock as the uart driving clock. From software perspective, you can use clock configuration to select the external clock as uart clock.

Hope it can help you

XiangJun Rong