Hello ....

I was just going through some of the previous posts on serial communications and I would like to have a few clarifications :





With a 11.0592 crystal and using serial interrupt , and a ring buffer for temporary storage ,is it likely that if the code size is big enough the serial interrupts come rapidly enough to overwrite the buffer ? If there is sufficient RAM avlbl on chip ( 89C51RD2xx ) , how does one optimise ( calculate ) the size of the ring buffer to avoid this ?

When J Guy says that 18.432 MHz will give the same baud rate and be faster , what does it mean ? 115200 baud should be the same whether 18.432 or 11.0592 . Or is it just that he means the code will be processed faster so that buffer overwrite does not happen .

If a board is working well with a 12 MHz chip , will there be any problems if I pluck it out and replace with a 20 MHz , asuuming there are no timing implications on the software side ?

By the way, many thanks to all who contributed on my earlier post on the batteries. It really opened up new vistas , especially since I am not an electronics engineer and scrambling to pick up the concepts.

Thomas