- Mon Jun 22, 2009 5:20 pm
#75545
I have an Olimex MSP430F149 prototype bard shown here: http://www.sparkfun.com/commerce/produc ... cts_id=583
I have used the RS232 interface successfully at 9600 using the watch crystal. I've tried two high frequency crystals (8 MHz and 1.8432 MHz) in the Q3 socket. In both cases I can put the high frequency clock from the crystal in Q3 to a pin and view on an oscilloscope. I did notice that the signals looked more like a squashed sine wave than a square wave....I know it's not going to be perfect, but it that may be part of my problem....read on.....
My problem is that I can't use these high frequency crystals to drive the UART. I'm using TI's examples, some exact and some slightly modified, but get nothing. I expect it is not a software problem....I think I understand the software configuration b/c the documentation is very good. Should I add additional caps? Any ideas would be appreciated.
Thanks in advance.
I have used the RS232 interface successfully at 9600 using the watch crystal. I've tried two high frequency crystals (8 MHz and 1.8432 MHz) in the Q3 socket. In both cases I can put the high frequency clock from the crystal in Q3 to a pin and view on an oscilloscope. I did notice that the signals looked more like a squashed sine wave than a square wave....I know it's not going to be perfect, but it that may be part of my problem....read on.....
My problem is that I can't use these high frequency crystals to drive the UART. I'm using TI's examples, some exact and some slightly modified, but get nothing. I expect it is not a software problem....I think I understand the software configuration b/c the documentation is very good. Should I add additional caps? Any ideas would be appreciated.
Thanks in advance.