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Delay in UART transmission at highbaud rates

Question asked by shafy s on Feb 22, 2017
Latest reply on Feb 23, 2017 by Clive One

Hi, I am developing an application using STM32L432 nucleo32 board, that samples 5 ADC channels and send that the data to UART.   The ADC channels are sampled using a timer and the maximum sampling frequency can be 10kHz.  So there can be 10K timer events. 

But I am facing some bottle neck in the UART.. even with baud rate of 921 kbps , the UART is causing delay in the transmission of the samples.  The 10K samples, ie 100000 bytes takes around 10 sec to reach the receiving end which is a PC terminal. For testing, I have removed the ADC sampling and tried sending hard coded data and getting the same result.  We have tried higher Baud rates (>1.5 Mbps), with little improvement.  The uart clock used is 32 MHz.  Is there a way to decrease this latency ?

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