From 17406fa8a5c4142226131b45ce7675660672ac95 Mon Sep 17 00:00:00 2001
From: jaredairbusaerial <42249132+jaredairbusaerial@users.noreply.github.com>
Date: Sun, 13 Jan 2019 21:18:05 -0500
Subject: [PATCH] Added safety notice for PWM input.

---
 docs/hoverboard.md | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/docs/hoverboard.md b/docs/hoverboard.md
index 1c0f0ce3..9641ae6d 100644
--- a/docs/hoverboard.md
+++ b/docs/hoverboard.md
@@ -120,7 +120,7 @@ odrv0.axis0.requested_state = AXIS_STATE_IDLE
 Hopefully you got your motor to spin! Feel free to repeat all of the above for the other axis if appropriate.
 
 ### PWM input
-If you want to drive your hoverboard wheels around with an RC remote contro you can use the [RC PWM input](interfaces.md#rc-pwm-input). There is more information in that link.
+If you want to drive your hoverboard wheels around with an RC remote control you can use the [RC PWM input](interfaces.md#rc-pwm-input). There is more information in that link.
 Lets use GPIO 3/4 for the velocity inputs so that we don't have to disable UART.
 Then let's map the full stick range of these inputs to some suitable velocity setpoint range.
 We also have to reboot to activate the PWM input.
@@ -161,6 +161,9 @@ odrv0.axis0.requested_state = AXIS_STATE_CLOSED_LOOP_CONTROL
 odrv0.axis1.requested_state = AXIS_STATE_CLOSED_LOOP_CONTROL
 ```
 
+### Safety
+Be sure to setup the Failsafe feature on your RC Receiver so that if connection is lost between the remote and the receiver, the receiver outputs 0 and 0 for the velocity setpoint of both axes (or whatever is safest for your configuration). Also note that if the receiver turns off (loss of power, etc) or if the signal from the receiver to the ODrive is lost (wire comes unplugged, etc), the ODrive will continue the last commanded velocity setpoint. There is currently no timeout function in the ODrive for PWM inputs.
+
 ### Automatic startup
 Try to reboot and then activate AXIS_STATE_CLOSED_LOOP_CONTROL on both axis. Check that everything is operational and works as expected.
 If so, you can now make the ODrive turn on the motor power automatically after booting. This is useful if you are going to be running the ODrive without a PC or other logic board.