LPC8xx, UART and the (lack of) seperate baudrate generators...

[lpcware]

Content originally posted in LPCWare by cgroen on Wed Dec 30 11:29:15 MST 2015
I know this is just "how it is", but it amazes me that the LPC8xx (824 in my case) has all the bells and whistles such as SWM, SCT, MRT like all its bigger LPCxxx cousins. When it then comes to the 3 UARTS, you are stuck with one single fractional baudrate generator.

It might be me that are just not seeing "it", but I think this is a pity...You have to balance the fractional divider with the needed baudrates for all 3 UARTS (I need to run 100KBaud) in two UARTS and 115200 on the last.
What is the best way to achieve this ? (my generated baudrates are not very precise)

[lpcware]

Content originally posted in LPCWare by cgroen on Thu Dec 31 03:44:02 MST 2015
Yeah, figured something like that would be the solution.
It just irritates me with such a limitation on a CPU that is otherwise filled with goodies :(

[lpcware]

Content originally posted in LPCWare by lpc_bloke on Thu Dec 31 02:24:45 MST 2015
Firstly I have not used all 3 UARTS.  But I needed 250K main and 115200 for the monitor.
In order to find a divisor that would allow me to do both I changed the CPU clock to 28MHz this allows me to get the all the UART speeds I needed.

I suggest you try something similar.

I order to find this magic speed I put all the numbers into a spread sheet and figured out the best combination.

Hope this helps.