#4204 NORM Never A: Batter meter never reaches 100%

[Zarro Boogs per Child]

#4204: Batter meter never reaches 100%
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  Reporter:  Eben    |       Owner:  edsiper       
      Type:  defect  |      Status:  new           
  Priority:  normal  |   Milestone:  Never Assigned
 Component:  sugar   |     Version:                
Resolution:          |    Keywords:                
  Verified:  0       |  
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Comment(by rsmith):

 Replying to [ticket:4204 Eben]:
 > Although the text in the palette states "Battery fully charged", neither
 the meter or the icon for the battery every reach the 100% mark, despite
 the fact that the computer has been plugged in for weeks.

 This is a result of using the values reported from the EC directly.  The
 BMS system uses the actual capacity of the battery in its measurements but
 stop charging short of 100% to extend the life of the batteries.  The
 reported % from the EC will be 10% <= x <= 90%.  +/- a few %.  The actual
 cutoff and full charge % depends on physical characteristics of the
 battery so each one is slightly different.

 > From the user experience perspective, seeing those graphical elements
 reach their full mark is really important, even if in truth capacity is
 slightly lower.

 The same thing will happen on the low side as well... The red light will
 be on but the the meter will still say 10%. 10% really equals about 2-3%.
 The display probably needs to scale the output.  I think the following
 should work.

 Scaled% = (int)((1.25 * (float)EC%) - 12.5)

 if (Scaled% > 100) Scaled%  = 100;
 if (Scaled% < 0) Scaled% = 0;

 But because the actual "Full" from the EC will vary there will be cases
 where the meter and the EC won't match.  The meter will say 100% and the
 EC will still have the yellow light on.

 Perhaps the meter should hold at 99% until the EC says "full" and then
 jump to 100%.

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Ticket URL: <https://dev.laptop.org/ticket/4204#comment:1>
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