Data, Read, & Target variable

Archiver

I am using a tilt sensor in an automatic leveling application.

My target variable that indicates a level position (90 degrees for the sake
of this argument) is 1780.

if the sensor is at 80 degrees it returns a value of 1710 (-70 from target)
and if the sensor is at 100 degrees it returns 1860 (+70 from target). I
would like to use the difference to control the level correction speed using
a "read / Data" table. Is there a simple way to ignore the sign and just
use the value of the result?

i.e.,

Correction_speed data 50,100,200,500,2000
speed var word
X var word

Get_sensor X (lets just say X =1760)
read correction_speed + (1780-x/10), speed

in this example speed will have the value of the "2" in eeprom (200). But if
my sensor is on the other side of level and returns a value of 1800, the
result will be a negative number.

i.e.,

Correction_speed data 50,100,200,500,2000
speed var word
X var word

Get_sensor X (lets just say X =1800)
read correction_speed + (1780-x/10), speed

this time we get a -2

I know there has to be a simple solution for a simple problem. Any help
would be appreciated. Thanks

Jeff

Archiver

Jeff,

y = abs x

the absolute value of x


> I am using a tilt sensor in an automatic leveling application.
>
>My target variable that indicates a level position (90 degrees for the sake
>of this argument) is 1780.
>
>if the sensor is at 80 degrees it returns a value of 1710 (-70 from target)
>and if the sensor is at 100 degrees it returns 1860 (+70 from target). I
>would like to use the difference to control the level correction speed using
>a "read / Data" table. Is there a simple way to ignore the sign and just
>use the value of the result?
>
>i.e.,
>
>Correction_speed data 50,100,200,500,2000
>speed var word
>X var word
>
>Get_sensor X (lets just say X =1760)
>read correction_speed + (1780-x/10), speed
>
>in this example speed will have the value of the "2" in eeprom (200). But if
>my sensor is on the other side of level and returns a value of 1800, the
>result will be a negative number.
>
>i.e.,
>
>Correction_speed data 50,100,200,500,2000
>speed var word
>X var word
>
>Get_sensor X (lets just say X =1800)
>read correction_speed + (1780-x/10), speed
>
> this time we get a -2
>
>I know there has to be a simple solution for a simple problem. Any help
>would be appreciated. Thanks
>
>Jeff

Archiver

D'oh. That hurt! [noparse]:)[/noparse]

Thanks Tracy!.