PHP mySQL Time Between Rows

Hello I am stuck on this. Looking to be able to pull the time between 2 start/stop rows from a mySQL database. My table looks like this

fillercdown_ndx |  time                 | B3_4_5
1               |  2016-06-16 14:59:45  | 0
2               |  2016-06-16 15:03:11  | 1

Basically when its recorded as 0 the machine stopped and when the record is 1 the machine restarted. I need to be able to calculate the amount of time the machine was down between certain times like 8AM-5PM. Was going to use PHP to display it upon users time entered, but have no idea on the SQL command.

Anyone know the best way to be able to find this?

Create table

CREATE TABLE `fillercdown` (
 `fillercdown_ndx` int(11) NOT NULL AUTO_INCREMENT,
 `time` datetime DEFAULT NULL,
 `B3_4_5` int(11) DEFAULT NULL,
 PRIMARY KEY (`fillercdown_ndx`),
 KEY `fillercdowntimendx` (`time`)
) ENGINE=InnoDB AUTO_INCREMENT=7 DEFAULT CHARSET=latin1

UPDATE:

There will be hundreds of these "start" and "stop" entries. My end all goal would be in php to give the user a small form asking them to provide a time range like 8AM-5PM and then be able to calculate all the time where the machine was "stopped" (which is when B3_4_5 is at 0). I just can't seem to figure out the right SQL call to get the time differences between each 0 and 1 and add them together between a set time range