topic Re: Getting higher baud rate usart with 72Mhz in LPC Microcontrollers

Getting higher baud rate usart with 72Mhz

lpcware — Wed, 15 Jun 2016 16:56:53 GMT

Content originally posted in LPCWare by aamir ali on Sat Aug 10 05:21:04 MST 2013
I read formula on page 223 of Um10524 which gives max baud rate. I am operating uart at 72Mhz.

By this formula I get max baud rate as: 409090. with 8 data , 1 stop & no parity

I have use it for 921600. I think this can be done if oversampling is done by x8 instead of x16. But I think there is no setting.

But LPC1315/16/17/45/46/47 product datsheet says that:
"Maximum USART data bit rate of 3.125 Mbit/s"

How to achieve higher baud rate

Re: Getting higher baud rate usart with 72Mhz

lpcware — Wed, 15 Jun 2016 16:56:54 GMT

Content originally posted in LPCWare by Wouter on Wed Aug 14 01:47:19 MST 2013
Hi,

The formula you refer to is only valid when using the auto-baud function.
Please refer to Chapter 12.5.14.1 "Baud rate calculation" to find more details on how to configure the baud rate.

Regards,
Wouter

Re: Getting higher baud rate usart with 72Mhz

lpcware — Wed, 15 Jun 2016 16:56:55 GMT

Content originally posted in LPCWare by aamir ali on Sun Aug 18 01:20:49 MST 2013
But in that case I can have max baud rate = 4,500,000 bits sec.

by setting UARTCLKDIV = 1 & PCLK = 72MHZ, DLL = 1, DLM = 0, DIV = 0 , MUL = 1;

Then max baud rate = 4,500,000.

But product datasheet of LPC1317 says "Maximum USART data bit rate of 3.125 Mbit/s."

Where I am getting it wrong