martin jean

rising edge detection

Discussion created by martin jean on Jun 11, 2010
Latest reply on Jun 18, 2010 by martin jean



i'm working on a project with the MCF52259 demokit board. We have to implement a sonic waves sensor.

A command is sent to the sensor (trigger pulse 50us) and the sensor answers with an echo pulse from 100us to 50ms (depends on the detected distance). The microcontroler has to count the pulse width.


The problem I have is the microcontroler doesn't detect the rising edge on the output sensor (the pin used is the first pin of the TC GPIO port). I supppose the gpio is bad configured but i dont know where is the problem.


I notice the MCF_GPIO_PORTTC port is connected to the leds and used to display them but I dont think that could be the problem.