Sub Main()

ToolNumberDRO=824	'set the OEM Code 824 to a variable
Capacity=8 		'tool holder capacity
pos1=0			'initialize position variables to zero
pos2=0
pos3=0
pos4=0
pos5=0
pos6=0
pos7=0
pos8=0

count = 0 		'initialize count variables to zero
done  = 0		'initialize done variable to zero

OldTool=GetCurrentTool 	'get tool# that Mach3 thinks is in turret.  This is used only to maintain
			'existing tool# In DRO-824 If macro exits before ending.
NewTool=GetSelectedTool 'get the new commanded tool# from G-Code 'TX01M6'

setOEMDRO(ToolNumberDRO,OldTool)	'set DRO 824 to the currently stored Mach3 tool#.
					'NewTool only gets input if macro executes properly

'-------
'check to see if new tool# makes sense

If NewTool > Capacity Then
	Message("Tool Number Too High, range 1-"&Capacity)
	code "M00"
	Exit Sub	
End If


If NewTool < 1 Then
	Message("Tool Number Too low, range 1-"&Capacity)
	code "M00"
	Exit Sub
End If

'-------
'Everything seems to be OK so-far, get the current tool position in the turret directly from PLC
'by polling the 8-positin reed switch. If a switch position is closed, that is the current tool

pos1=GetInput(0)
pos2=GetInput(1)
pos3=GetInput(2)
pos4=GetInput(3)
pos5=GetInput(4)
pos6=GetInput(5)
pos7=GetInput(6)
pos8=GetInput(7)

'-------
'set the current tool # based on which switch is closed
 
If pos1=1 Then CurrentTool=1
If pos2=1 Then CurrentTool=2
If pos3=1 Then CurrentTool=3
If pos4=1 Then CurrentTool=4
If pos5=1 Then CurrentTool=5
If pos6=1 Then CurrentTool=6
If pos7=1 Then CurrentTool=7
If pos8=1 Then CurrentTool=8

'-------
'This makes sure that the turret is actually in a valid position
'if no switch is closed or if multiple switches are closed there is a problem

If pos1+pos2+pos3+pos4+pos5+pos6+pos7+pos8 <> 1 Then					
	Message("turret switch broken, or turret out of position, pausing program")	
	code "M00"
	Exit Sub
End If

'-------
'check to see if new tool# = CurrentTool#.  If so, nothing needs to happen, exit.

If NewTool = CurrentTool Then
	Message("Old Tool = New Tool, Returning")
	setOEMDRO(ToolNumberDRO,CurrentTool)		'This is here because we now know which tool the PLC
							'thinks is in position, and that should be correct.
	code "M00"
	Exit Sub					
End If

'-------
'Figure out which direction to turn the turret for the shortest toolchange


difference=NewTool-CurrentTool			'Subtract the current tool from the new tool
	
If difference < 0 Then difference=difference+8	'If the difference is negative, then add it to 8 so the number is between 1-8
direction = 8-difference			'This is a little hard to explain without a picture, but basically if you
						'subtract old from new tool you get numbers from -7 to 7.  If you force all those to
						'be positive by adding the negative ones to 8 (in other words if you get -3, add it to 8
						'for a sum of 5) and then subtract that from 8, you get the numbers 1-7.  1,2,3 are one
						'direction, and 7,6,5 are the other.  4 does not matter, same distance either way.

If direction = 1 Then SetModOutput (0,0)	'sets motor direction clockwose facing -Z
If direction = 2 Then SetModOutput (0,0)	'sets motor direction clockwose facing -Z
If direction = 3 Then SetModOutput (0,0)	'sets motor direction clockwose facing -Z
If direction = 4 Then SetModOutput (0,0)	'sets motor direction clockwose facing -Z
						'direction does not matter here, but might as well go the same way
						
If direction = 5 Then SetModOutput (0,1)	'sets motor direction counter clockwose facing -Z
If direction = 6 Then SetModOutput (0,1)	'sets motor direction counter clockwose facing -Z
If direction = 7 Then SetModOutput (0,1)	'sets motor direction counter clockwose facing -Z

'-------
'Actually do the tool change, now that the direction relay is set the PLC does not need to deal with that.

If NewTool=1 Then								'Check to see which tool is being called
	Do
	count = count + 1							'Add one to count.  This routine polls the "done" signal from the PLC every 100msec.										
	SetModOutput(1,1)							'initiate tool change routine for selected tool
	sleep 100								'Let run 100msec
	done = GetInput(73)							'Checkt to see if PLC is done
	If done=1 Then Exit Do							'If it is done, quit waiting
		If count > 100 Then						'Check to see if more than 10 sec, if not, keep waiting.  Should take 5 sec for longest change
			Message ("tool change timed out, pausing program")	'If timeout, send message
			SetModOutput(1,0)					'if timeout, turn off PLC routine
			code "M00"						'If timeout, pause G-code
			Exit Sub
		End If
	Loop
	SetModOutput(1,0)							'if exiting loop, reset PLC routine off	(not sure I need to do this?)
	done=0									'Reset done to zero (not sure I need to do this?)
	End If

'-------

If NewTool=2 Then
	Do
	count = count + 1
	SetModOutput(2,1)
	sleep 100
	done = GetInput(73)
	If done=1 Then Exit Do
		If count > 100 Then
			Message ("tool change timed out, pausing program")
			SetModOutput(2,0)
			code "M00"
			Exit Sub
		End If
	Loop
	SetModOutput(2,0)
	done=0
	End If

'-------

If NewTool=3 Then
	Do
	count = count + 1
	SetModOutput(3,1)
	sleep 100
	done = GetInput(73)
	If done=1 Then Exit Do
		If count > 100 Then
			Message ("tool change timed out, pausing program")
			SetModOutput(3,0)
			code "M00"
			Exit Sub
		End If
	Loop
	SetModOutput(3,0)
	done=0
	End If

'-------
	
If NewTool=4 Then
	Do
	count = count + 1
	SetModOutput(4,1)
	sleep 100
	done = GetInput(73)
	If done=1 Then Exit Do
		If count > 100 Then
			Message ("tool change timed out, pausing program")
			SetModOutput(4,0)
			code "M00"
			Exit Sub
		End If
	Loop
	SetModOutput(4,0)
	done=0
	End If

'-------
	
If NewTool=5 Then
	Do
	count = count + 1
	SetModOutput(5,1)
	sleep 100
	done = GetInput(73)
	If done=1 Then Exit Do
		If count > 100 Then
			Message ("tool change timed out, pausing program")
			SetModOutput(5,0)
			code "M00"
			Exit Sub
		End If
	Loop
	SetModOutput(5,0)
	done=0
	End If

'-------

If NewTool=6 Then
	Do
	count = count + 1
	SetModOutput(6,1)
	sleep 100
	done = GetInput(73)
	If done=1 Then Exit Do
		If count > 100 Then
			Message ("tool change timed out, pausing program")
			SetModOutput(6,0)
			code "M00"
			Exit Sub
		End If
	Loop
	SetModOutput(6,0)
	done=0
	End If

'-------
	
If NewTool=7 Then
	Do
	count = count + 1
	SetModOutput(7,1)
	sleep 100
	done = GetInput(73)
	If done=1 Then Exit Do
		If count > 100 Then
			Message ("tool change timed out, pausing program")
			SetModOutput(7,0)
			code "M00"
			Exit Sub
		End If
	Loop
	SetModOutput(7,0)
	done=0
	End If

'-------

If NewTool=8 Then
	Do
	count = count + 1
	SetModOutput(8,1)
	sleep 100
	done = GetInput(73)
	If done=1 Then Exit Do
		If count > 100 Then
			Message ("tool change timed out, pausing program")
			SetModOutput(8,0)
			code "M00"
			Exit Sub
		End If
	Loop
	SetModOutput(8,0)
	done=0
	End If

'I may add in here a little section to re-read the reed switches and verify the tool position just as another safety feature	
		
setOEMDRO(ToolNumberDRO,CurrentTool)		'store the new tool in DRO 824 now that everything is done and proper
	
sleep 500					'For some reason I need this for back-to-back tool changes to work properly?

End Sub
Main