ROB LUND

SCI won't run without Multilink?

Discussion created by ROB LUND on Apr 9, 2008
Latest reply on Jul 4, 2008 by Jim Donelson
Hey gang, I continue to have fun with the SCI UART.  My RS232 code is actually coming along nicely.  But the latest realization is that I seem to need my USB Multilink programmer attached to my target in order for the UART to work.  Nothing seems to spit out of the TX pin unless the programmer is attached via the BDM 6-pin header.  Darnedest thing.

I have the following code in my source for setting the trim:

Code:
volatile Byte NV_FTRIM_INIT @0x0000FFAE;volatile Byte NV_ICSTRM_INIT @0x0000FFAF; // instantiate the nonvolatile ICS Trim Registerif (NV_ICSTRM_INIT != 0xFF){  ICSTRM = NV_ICSTRM_INIT;  // load trim value if location not blank}

And of course I am using the PT command in the P&E programming software to program the trim values in FFAE:FFAF.

Any ideas why the programmer must be present?  My guess is that it must be doing something special to the BKGD or Reset lines that my target is not.  My target pulls both of these up to 3.3V through a 3.3K resistor.

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