Converting tfDist into meters

[Andy Kim]

Hi Bud,

Using your example code, I would like to convert the tfDist value, which is outputted in centimeters, into meters. I have tried performing math using a double:

if ( tfmP.getData( tfDist, tfFlux, tfTemp)) // Get data from the device.
{
double tfMeter;
tfMeter = tfDist / 100.0;
printf( " Dist: %f", tfMeter); // Display the distance.
break; // Escape this sub-loop
}

However, it always outputs something like:

Loop:01 Dist: ?
Loop:02 Dist: ?
Loop:03 Dist: ?
Loop:04 Dist: ?
Loop:05 Dist: ?

Do you have any idea of how I could solve this issue? I am not sure, it may be because tfDist is a uint16_t integer type, but I am not sure how I would fix it regardless. Hope you can help, thank you.

[Bud Ryerson]

Hey AndyK,
Try recasting tfDist as a floating point number: tfMeter = (float)tfDist / 100.0;
Let me know what happens.
Bud

[Andy Kim]

Yep, it worked! Thank sorry for not responding sooner.

I ran into another issue though. I am using an Arduino Uno and am trying to use the sensor with a button as well. I use Software Serial and included mySerial to get the TFMini-Plus working, because I did not know how to get it to work any other way. However, for some reason, this makes my button act weirdly, making it simply not act as a button. It's either always on or off.
Any help?

[Bud Ryerson]

Andy,
Your question is too vague for me to answer. Please provide a more thorough explanation of the problem. A sample of your code would be helpful. And pictures or a wiring diagram, too.
Bud