On Wednesday 14 February 2007 12:52, Yang Peng wrote: > Hi all, > > I have a question about the DAC driver for Tmote sky node. > > Can anybody tell me some information about following definition? I cannot > find useful info in msp430 data sheet, neither in the comments for the > driver code. > (I am very appreciated that any nice guy can tell me where to find a detail > description about the registers in msp430f1611) > > I find following in usr/local/mspgcc/msp430/include/msp430/dac12.h > > #define DAC12GRP 0x0001 /* DAC12 group */ what's dose this > group mean?
Allows the 2 DACs on the '1611 to have changes to their outputs synchronized. > #define DAC12DF 0x0010 /* DAC12 data format */ what's the > two types of format? Whether the data provided to the DAC is an unsigned value or a 2's complement signed value. In the former case, 0 means the lowest DAC output, while in the latter case 0 means a mid-range output. > #define DAC12LSEL0 0x0400 /* DAC12 load select bit 0 */ what dose > 'load select' mean? > #define DAC12LSEL1 0x0800 /* DAC12 load select bit 1 */ DAC12LSELx is a 2-bit value that defines how an input datum value is loaded into the DAC (i.e. reflected on the output). Go to www.ti.com/msp430 and get the msp430 User's Guide (pdf). The DAC and all the other perhipherals are covered within it. There are also part-specific (well, part-group specific) data sheets, so you might want to get the one that covers the '1611. > > Another question is that: Is it a must to use DMA while using DAC for Tmote > Sky? No. > > Thanks for your help. You're welcome! _______________________________________________ Tinyos-help mailing list Tinyos-help@Millennium.Berkeley.EDU https://mail.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help
