diff --git a/src/drivers/drv_pwm_output.h b/src/drivers/drv_pwm_output.h
index 84815fdfbb..5aff6825be 100644
--- a/src/drivers/drv_pwm_output.h
+++ b/src/drivers/drv_pwm_output.h
@@ -94,6 +94,11 @@ __BEGIN_DECLS
  */
 #define PWM_LOWEST_MAX 1700
 
+/**
+ * Do not output a channel with this value
+ */
+#define PWM_IGNORE_THIS_CHANNEL UINT16_MAX
+
 /**
  * Servo output signal type, value is actual servo output pulse
  * width in microseconds.
diff --git a/src/drivers/px4fmu/fmu.cpp b/src/drivers/px4fmu/fmu.cpp
index 82977a032f..122a3cd174 100644
--- a/src/drivers/px4fmu/fmu.cpp
+++ b/src/drivers/px4fmu/fmu.cpp
@@ -1272,7 +1272,9 @@ PX4FMU::write(file *filp, const char *buffer, size_t len)
 	memcpy(values, buffer, count * 2);
 
 	for (uint8_t i = 0; i < count; i++) {
-		up_pwm_servo_set(i, values[i]);
+		if (values[i] != PWM_IGNORE_THIS_CHANNEL) {
+			up_pwm_servo_set(i, values[i]);
+		}
 	}
 
 	return count * 2;
diff --git a/src/modules/px4iofirmware/registers.c b/src/modules/px4iofirmware/registers.c
index 43161aa70e..0da778b6f6 100644
--- a/src/modules/px4iofirmware/registers.c
+++ b/src/modules/px4iofirmware/registers.c
@@ -285,7 +285,9 @@ registers_set(uint8_t page, uint8_t offset, const uint16_t *values, unsigned num
 		while ((offset < PX4IO_CONTROL_CHANNELS) && (num_values > 0)) {
 
 			/* XXX range-check value? */
-			r_page_servos[offset] = *values;
+			if (*values != PWM_IGNORE_THIS_CHANNEL) {
+				r_page_servos[offset] = *values;
+			}
 
 			offset++;
 			num_values--;