4.6:RPM_instances

common/source/docs/common-rpm.rst

@@ -85,7 +85,7 @@ First the board needs to be configured to allow PWM pins to be set for GPIO.  Th
 
 .. note:: in firmware versions 4.2 and later, the method for setting a PWM/SERVO/MOTOR output to be a GPIO function is changed. Instead of ``BRD_PWM_COUNT`` being used, the individual ``SERVOx_FUNCTION`` parameter is merely set to "-1". If set to "0", it remains a PWM output, unassigned to a function, and outputs that output's trim value when board safety is not active. If the servo function is being "mirrored" to a remote device, as in the case of a DroneCAN or KDECAN ESC, then in order to change the autopilot board's corresponding output pin to be a GPIO, but allow the ``SERVOx_FUNCTION`` to still be assigned to the remote device, the :ref:`SERVO_GPIO_MASK<SERVO_GPIO_MASK>` parameter can be used to assign the board pin to be a GPIO without affecting the ``SERVOx_FUNCTION`` assignment for the remote device.
 
-Now the RPM library must be enabled. In the following sections, we will use the second instance of RPM sensor for parameter examples.
+Now the RPM library must be enabled. In the following sections, we will use the second instance of RPM sensor for parameter examples. Up to four different sensors(instances) can be used.
 
 Set the parameter :ref:`RPM2_TYPE<RPM2_TYPE>` to 2 for a GPIO pin based sensor.  Write the parameter to ArduPilot then refresh/fetch the 
 parameters.  You will now find that the instance of RPM (e.g. RPM2) has a number of other parameters available for editing, allowing you to complete your setup.
@@ -101,11 +101,6 @@ The parameter :ref:`RPM2SCALING<RPM2_SCALING>` will correspond to the number mag
 
 Initially, it is recommended to leave the parameters :ref:`RPM2_MIN<RPM2_MIN>`, :ref:`RPM2_MAX<RPM2_MAX>`, and :ref:`RPM2_MIN_QUAL<RPM2_MIN_QUAL>` as their defaults.  If an RPM signal exceeds any of these limits then the value reported in the ground station and the logs is zero.  Therefore, only adjust these values once you have confirmed that your RPM sensor is working as expected, otherwise it can make it more difficult to debug if nothing is getting reported.
 
-.. note::
-
-    If using two RPM sensors the min, max, and quality parameters are valid for both of the RPM sensors.  In this case be sure to set these values to encompass the 
-    RPM ranges of both sensors.
-
 Finally, to test that everything is working, you can use the rpm1/rpm2 live feeds in the quick tab in mission planner or the live tuning window.  Alternatively the 
 RPM history can be reviewed in the logs.