diff --git a/src/PhpGpio/Gpio.php b/src/PhpGpio/Gpio.php
index eb79e1e..79b910a 100644
--- a/src/PhpGpio/Gpio.php
+++ b/src/PhpGpio/Gpio.php
@@ -98,6 +98,9 @@ public function setup($pinNo, $direction)
         // Export pin
         file_put_contents(GpioInterface::PATH_EXPORT, $pinNo);
 
+	// wait until pin is ready
+	while(!is_writable(GpioInterface::PATH_GPIO.$pinNo)) { /* empty */ }
+
         // if valid direction then set direction
         if ($this->isValidDirection($direction)) {
             file_put_contents(GpioInterface::PATH_GPIO.$pinNo.'/direction', $direction);