ROFLhoff 1 Posted October 16, 2013 Share Posted October 16, 2013 Hey guys, it's been a long time since I've used launchpads, and am re-learning some specifics with the value line chips. I had a couple G2231 chips laying around that I used to run a cheap HD44870 display to show the ADC10 Channel 10 & 11 readings (Temp/ .5Vcc). I also wanted to see the calibration data to understand how to use that for more accurate readings. Somewhere along the lines I had ran the TI dco_flashcal.c program on them so those values are gone. My question is how those values were made in the first place? Did TI throw their chips in a 30C/85C environment and sample the ADC for those calibration readings? I doubt I would use a several of those values but I'd like to know how to restore them sometime down the road. Quote Link to post Share on other sites
bluehash 1,581 Posted October 17, 2013 Share Posted October 17, 2013 Hey guys, it's been a long time since I've used launchpads, and am re-learning some specifics with the value line chips. I had a couple G2231 chips laying around that I used to run a cheap HD44870 display to show the ADC10 Channel 10 & 11 readings (Temp/ .5Vcc). I also wanted to see the calibration data to understand how to use that for more accurate readings. Somewhere along the lines I had ran the TI dco_flashcal.c program on them so those values are gone. My question is how those values were made in the first place? Did TI throw their chips in a 30C/85C environment and sample the ADC for those calibration readings? I doubt I would use a several of those values but I'd like to know how to restore them sometime down the road. Not sure how they do it. But try this link. Quote Link to post Share on other sites
ROFLhoff 1 Posted October 19, 2013 Author Share Posted October 19, 2013 Thanks for the reply, I took a deeper look at the MSP430x2xx User Guide (AKA SLAU144) and the G2231 datasheet/errata) and looked at the TLV section. It looks like the constants CAL_ADC_15T30 and similar can be found with a temperature-controlled enclosure, but might need two other constants to be set correctly: Offset and gain factor calibrations. The User Guide only demonstrates using those constants to correct raw ADC values, and I don't see a way to work backwards for the constants. Unless I'm reading the section wrong(SLAU144j: 22.2.4-5) there are two variables to adjust from only one input variable. A system of equations can't be used to get rid of one variable AFAIK. Quote Link to post Share on other sites
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