Crystal AFC check fail(MT6253平.

rystal CAPID check begin
CAPID=38,AFC DAC=0,FreqErr=-8791.5
FAIL: Crystal AFC check:-9.7
CAPID=38,AFC DAC=8191,FreqErr=34984.0
PASS: Freq error PPM =38.7
CAPID=39,AFC DAC=0,FreqErr=-9435.7
FAIL: Crystal AFC check:-10.4
CAPID=39,AFC DAC=8191,FreqErr=34250.2
PASS: Freq error PPM =37.9
CAPID=40,AFC DAC=0,FreqErr=-10078.7
FAIL: Crystal AFC check:-11.2
CAPID=40,AFC DAC=8191,FreqErr=33520.6
PASS: Freq error PPM =37.1
CAPID=41,AFC DAC=0,FreqErr=-10723.1
FAIL: Crystal AFC check:-11.9
CAPID=41,AFC DAC=8191,FreqErr=32788.9
PASS: Freq error PPM =36.3
CAPID=42,AFC DAC=0,FreqErr=-11357.6
FAIL: Crystal AFC check:-12.6
CAPID=42,AFC DAC=8191,FreqErr=32062.1
PASS: Freq error PPM =35.5
CAPID=43,AFC DAC=0,FreqErr=-11989.9
FAIL: Crystal AFC check:-13.3
CAPID=43,AFC DAC=8191,FreqErr=31341.3
PASS: Freq error PPM =34.7
CAPID=44,AFC DAC=0,FreqErr=-12618.9
FAIL: Crystal AFC check:-14.0
CAPID=44,AFC DAC=8191,FreqErr=30625.8
PASS: Freq error PPM =33.9
CAPID=45,AFC DAC=0,FreqErr=-13238.9
FAIL: Crystal AFC check:-14.7
CAPID=45,AFC DAC=8191,FreqErr=29911.4
PASS: Freq error PPM =33.1
CAPID=46,AFC DAC=0,FreqErr=-13855.9
FAIL: Crystal AFC check:-15.3
CAPID=46,AFC DAC=8191,FreqErr=29196.8
PASS: Freq error PPM =32.3
CAPID=47,AFC DAC=0,FreqErr=-14471.4
FAIL: Crystal AFC check:-16.0
CAPID=47,AFC DAC=8191,FreqErr=28492.7
PASS: Freq error PPM =31.6
CAPID=48,AFC DAC=0,FreqErr=-15072.7
FAIL: Crystal AFC check:-16.7
CAPID=48,AFC DAC=8191,FreqErr=27794.6
PASS: Freq error PPM =30.8
CAPID=49,AFC DAC=0,FreqErr=-15675.3
FAIL: Crystal AFC check:-17.4
CAPID=49,AFC DAC=8191,FreqErr=27096.9
PASS: Freq error PPM =30.0
CAPID=50,AFC DAC=0,FreqErr=-16279.0
PASS: Freq error PPM =-18.0
CAPID=50,AFC DAC=8191,FreqErr=26400.5
PASS: Freq error PPM =29.2
请问这是怎么回事？crystal问题吗？不过我用的crystal是MTK认证过的啊

这里的FreqErr怎么绝对值越大就过（好像要大于16,000），小反而过不了，怎么解释啊！？

这里的FreqErr怎么绝对值越大就过（好像要大于16,000），小反而过不了，怎么解释啊！？

不是FreqErr绝对值的问题，而是PASS: Freq error PPM =-18.0与PASS: Freq error PPM =29.2 这两个PPM值的绝对值之差应该小于10吧，

看了一下程序，发现时这样判断的：
if( (FreqErrorPPM =0)|| (FreqErrorPPM > d_min_frequency_err_ppm && FreqErrorPPM < 0) )
sprintf (tempbuf, "\nFAIL: Crystal AFC check:%.1f",FreqErrorPPM);
d_max_frequency_err_ppm = （ 890 + 0.2*AFC_ARFCN ）* CRYSTAL_AFC_MAX_FREQ_ERR_PPM
d_min_frequency_err_ppm 是负的
楼主的配置文件里CRYSTAL_AFC_MAX_FREQ_ERR_PPM = 18
所以check的FreqErr必须大于16254或小于-16254
但是为啥这样判断呢·？资深工程师指点一下！

CFG文件如下：
[Crystal AFC Calibration]
CRYSTAL_AFC_BAND = GSM
CRYSTAL_AFC_ARFCN = 65
CRYSTAL_AFC_GSM850_PCL = 14
CRYSTAL_AFC_GSM900_PCL = 14
CRYSTAL_AFC_DCS1800_PCL = 7
CRYSTAL_AFC_PCS1900_PCL = 7
CRYSTAL_AFC_CAL_DAC = 4096
CRYSTAL_AFC_CHECK_DAC1 = 0
CRYSTAL_AFC_CHECK_DAC2 = 8191
CRYSTAL_AFC_MIN_FREQ_ERR_PPM = -18.0
CRYSTAL_AFC_MAX_FREQ_ERR_PPM = 18.0
CRYSTAL_AFC_MAX_AFC_TRACK_INIT_FREQ_ERR = 20
CRYSTAL_AFC_FREQ_ERR_MEASUSE_COUNT = 10
CRYSTAL_AFC_TRX_OFFSET_RECURSIVE_TIMES = 20

CRYSTAL_AFC_CAL_DAC = 4096改成6500就ok了。哈哈

这里的FreqErr怎么绝对值越大就过（好像要大于16,000），小反而过不了，怎么解释啊！？

AFC值偏大呀，晶体掏空了没有？还是线拉的太长？

下层都掏空了的。线也很短的。

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