Finding the mean value of several numbers Does it need to be fast ?
Otherwise just sort the numberes.
If it need to be used as a filter, I have routines somewhere (but no here) for 3 and 5 point "median" filteres.
Jens
PS...

Wednesday, 27 June 2007 - 16:34

Finding the mean value of several numbers For integer:
If you can live with the avg of a count of numbers be 2,4,8,16....
You just add the numberes and the rol (>>n) the number
down.
Ex.
sum 16 numberes (make sure that...

Tuesday, 26 June 2007 - 16:28

Timer1 overflow interrupt I don't know the timeing of the rest your project, but why not program the clk. prescaler as I remember you can program the clk to be down to 1/1024.
Jens

Friday, 22 June 2007 - 16:18

Searching for cheap LCD display? Take a look at
Sparkfun.com
They have a lot of displays,(and show photos of them) they have a colour display 128x128 with backligth for $19.99 and 20% off when you buy more than...

Friday, 22 June 2007 - 03:27

PIC vs AVR - Real world applications Atmel is founded in 1984!
And as I remember the hole thing started as a
Flash patent, and the founder came from Intel.
Jens

Thursday, 21 June 2007 - 03:24

16 bit division with high precision To do integer calc. you need to scale the numbers.
Like peret says 16 bit is fine.
Fine out what range tour numberes is in and find out where to put the decimal point. (remember...

how to "lookup data" First I asume that Edwards calc is correct (251.24 or 251.29).
Depending of speed needed I would do it in 32 bit int.
(Lux can't be in a 16bit anyway)
Something like this
(ADC) 10...

Thursday, 7 June 2007 - 16:33

how to "lookup data" First I hope that 626 should give 140000 not 14000
I just made a xy plot in excel and that show a nice straight line so lux = a*(ADC)+b !
Jens

Wednesday, 6 June 2007 - 16:41

Pack two byte to word A good compiler at full optimize should make something like this:
in R24,0x13
in R25,0x10
out 0x05,r25
out 0x04,r24
clr a reg before moveing a value into it, show that it's not...

Tuesday, 5 June 2007 - 20:03

how to "lookup data" 1)Are you programming in C or ASM ?
2)For a weather station you normaly use 3 letters for the compas (NNE for north north east).
3)You have to filter a bit so north show N and not...

Does it need to be fast ? Otherwise just sort the numberes. If it need to be used as a filter, I have routines somewhere (but no here) for 3 and 5 point "median" filteres. Jens PS...

For integer: If you can live with the avg of a count of numbers be 2,4,8,16.... You just add the numberes and the rol (>>n) the number down. Ex. sum 16 numberes (make sure that...

I don't know the timeing of the rest your project, but why not program the clk. prescaler as I remember you can program the clk to be down to 1/1024. Jens

Take a look at Sparkfun.com They have a lot of displays,(and show photos of them) they have a colour display 128x128 with backligth for $19.99 and 20% off when you buy more than...

Atmel is founded in 1984! And as I remember the hole thing started as a Flash patent, and the founder came from Intel. Jens

To do integer calc. you need to scale the numbers. Like peret says 16 bit is fine. Fine out what range tour numberes is in and find out where to put the decimal point. (remember...

I have not used it but "visualSTATE" from IAR could be a way! (I think you can get a free demo) Jens

Yes my mistake.

First I asume that Edwards calc is correct (251.24 or 251.29). Depending of speed needed I would do it in 32 bit int. (Lux can't be in a 16bit anyway) Something like this (ADC) 10...

First I hope that 626 should give 140000 not 14000 I just made a xy plot in excel and that show a nice straight line so lux = a*(ADC)+b ! Jens

A good compiler at full optimize should make something like this: in R24,0x13 in R25,0x10 out 0x05,r25 out 0x04,r24 clr a reg before moveing a value into it, show that it's not...

1)Are you programming in C or ASM ? 2)For a weather station you normaly use 3 letters for the compas (NNE for north north east). 3)You have to filter a bit so north show N and not...

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