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Calamar
Joined: 07 Sep 2003
Posts: 60
Location: Buenos Aires (Argentina)
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| Tabulation |
 Posted: Mon May 29, 2006 7:24 am |
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Someone know how to improve this:
(clock = 10 mhz, pulseTicks = width pulse,
rateFactor = 1 * 2 500 000
or
rateFactor = 60 * 2 500 000
or
rateFactor = 3600 * 2 500 000
or
rateFactor = 86400 * 2 500 000)
| Code: | if(timeUnitBuffer != timeUnit)
{
timeUnitBuffer = timeUnit;
switch(timeUnit)
{
case 0:
rateFactor = 250000000.0 / kFactor;
break;
case 1:
rateFactor = 150000000000.0 / kFactor;
break;
case 2:
rateFactor = 900000000000.0 / kFactor;
break;
case 3:
rateFactor = 21600000000000.0 / kFactor;
break;
default:
break;
}
}
rate = rateFactor / (float) pulseTicks;
if( rate > 99999.0 )
sprintf(strLineB," 99999 %s/%c", strVolumeUnit[volumeUnit], strTimeUnit[timeUnit]);
else
if( rate >= 1000.0 )
sprintf(strLineB," %5.0f %s/%c",rate, strVolumeUnit[volumeUnit], strTimeUnit[timeUnit]);
else
if (rate >= 100.0)
sprintf(strLineB," %3.1f %s/%c", rate, strVolumeUnit[volumeUnit], strTimeUnit[timeUnit]);
else
if (rate >= 10.0)
sprintf(strLineB," %2.2f %s/%c", rate, strVolumeUnit[volumeUnit], strTimeUnit[timeUnit]);
else
if (rate > 0.0009)
sprintf(strLineB," %1.3f %s/%c", rate, strVolumeUnit[volumeUnit], strTimeUnit[timeUnit]);
else
sprintf(strLineB," 0 %s/%c", strVolumeUnit[volumeUnit], strTimeUnit[timeUnit]);
} |
_________________
Best Regards
Daniel H. Sagarra
La Plata (Argentina) |
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PCM programmer
Joined: 06 Sep 2003
Posts: 21708
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| Posted: Mon May 29, 2006 3:41 pm |
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Tell us what your goal is, or what your project is about.
Also, Microchip floating point only has about 7 digits of resolution.
I'm not sure, but it looks like you may be assuming that it has 15
digits of resolution. |
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Calamar
Joined: 07 Sep 2003
Posts: 60
Location: Buenos Aires (Argentina)
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| Posted: Mon May 29, 2006 4:58 pm |
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I'm currenty using a capture module to measure
frecuency (10Mhz clock), the resolution requiered
is 0.1Hz, range 1.0 - 999.9 Hz --> 5 digits
| Code: | #INT_TIMER3
void tmr3_isr()
{
rollOver++;
if(rollOver == 20) pulseTicks = 0;
}
#INT_CCP2
void ccp2_isr()
{
static int16 startTime, endTime;
endTime = CCP_2;
pulseTicks = ( 0x10000 * rollOver ) - startTime + endTime;
startTime = endTime;
rollOver = 0;
} |
f = 2 500 000 00 / pulseTicks
^
|---------- Frecuency scaled * 100
but..... the measure could be represented in: seconds, minutes, hours, days
f = f * 1 or
f = f * 60 or
f = f * 3600 or
f= f * 86400
after that I divide f by kFactor (int32 type it was scaled by 100)
r = f / kFactor
(rate = frecuency * 100 / factor * 100)
now what I want is a right tabulation with 5 digit for any value of r,
for example
17456
1344.3
785.31
34.444
1.3546
0.0008
_________________
Best Regards
Daniel H. Sagarra
La Plata (Argentina) |
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PCM programmer
Joined: 06 Sep 2003
Posts: 21708
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| Posted: Mon May 29, 2006 5:45 pm |
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| Quote: | | I'm currently using a capture module to measure frequency |
Normally, a tachometer displays the speed in RPM (revolutions per minute).
Why do you care about seconds, hours, and days ?
Is this a tachometer project ? What device are you measuring ? |
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Calamar
Joined: 07 Sep 2003
Posts: 60
Location: Buenos Aires (Argentina)
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| Posted: Tue May 30, 2006 5:54 am |
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it's a flow computer, the signal
may come from a few diferents
types of sensors: TTL/CMOS, HALL,
COIL, take a look at:
http://www.fluidwell.com/f010.html?fseries
_________________
Best Regards
Daniel H. Sagarra
La Plata (Argentina) |
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