Digital Read Out Quadrature Encode Reader

This help tells about the functions of each screen and 
menu.  Read DRO.TXT with your favorite text editor to 
learn how to make your own simple interface to 
interact with the LPT port and your 5V encoders.

All the menus in the program have highlighted letters.  
Hitting that letter on your keyboard will take you to that 
function.  At any time to return to the previous menu 
press the ESC key.

When DRO is started the first screen is where the LPT 
port is chosen.  The default port is LPT1.  The setting 
of the IRQ# is unimportant if the IRQ is shut off (IRQ 
on/off in the lower right corner of the screen).  Shut 
the IRQ off in order to use the interface described in 
DRO.TXT.  The Time Display value is used when the 
IRQ is shut off.  The program uses the time display 
value while DRO is watching the port and displaying 
the incoming value changes to the screen.  When 
information begins to come in to fast (encoders are 
spinning fast) the program will stop updating to the 
screen and just concentrate watching the port and 
counting.  The time display value determines when the 
program should quit displaying to the screen and only 
concentrate watching the port.  Try to set this value to 
the smallest number without errors coming in.  Pertinent 
values are from 1 to 300.  The default is 10.  To view 
and/or change the Time Display value press the 't' key 
from the main menu.  Enter a new value or press ESC to 
return back to the main menu.

Press the 'r' key from the main menu to begin reading 
the port.  This encoder reader screen uses X, Y and Z 
to designate the 3 encoders.  The X axis is hooked to 
pins 2 and 3 of the LPT port, Y is hooked to 4 and 5, 
and Z is hooked to 6 and 7.   There is a quick zero 
reset for each axis from this screen.  They are F1 for 
X, F2 for Y and F3 for Z.  

There are four increment modes and one main Master 
Mode.  Press the 'm' key or space bar to toggle 
through them.  Each axis (encoder) has it own setup 
screen and depending if you are in Master mode or a 
increment mode the setup is different.  The 
increment mode is a more limited setup screen.  
Toggle the mode by pressing the space bar until you 
are in Master Mode.  Now press the 'x' key.  This takes 
you to the X axis (encoder1) Master setup screen.  
The available options in this setup are:

COUNTING UP/DOWN +/-  
To change the direction that encoder is counting.

RESET TO ZERO
To reset the encoder to zero.  Press it again to undo 
the rezero.  (F1 will do the same from the reading 
screen but there is no undo from there) 
 
CURRENT VALUE    
Enter in a new current value

UNIT TO COUNT BY 
Enter in a value for this encoder to count by (up to 14 
places to the right of the decimal).  

BACKLASH ON/OFF   
Use if you are hooking directly to a lead screw that 
has backlash.

LASH DISTANCE      
The backlash distance of the screw.

LASH TENSION DIR. 
Which way you want the tension of the lash to go from.
(Once you set this it will keep track of where you are 
in the backlash.  So if you take the backlash up the 
opposite of what it once was and rezero the axis it 
will automatically switch the "lash tension dir." for 
you.)

POSSIBLE ERRORS    
This will show a running count on the encoder reader 
screen of any possible errors.

PLACES SHOWN RIGHT OF DECIMAL 
How many places to the right of the decimal you would 
like displayed on the encoder reader screen.

F2 CONVERSION        
Menu to a inch to mm and mm to inch setup screen.

When you are finished entering in the data press the 
ESC key to return back to the encoder reader screen.

Press the space key to go to any other mode than the 
Master mode.  Now press the 'x' key.  This is the 
incremental mode setup screen.  The options are 
Reset to zero, Entering in a new current value and 
changing direction of counting +/-.  Press the ESC 
key to return back to the encoder reader screen.  

When you press the F1, F2 or F3, key to rezero from 
the encoder reader screen this will rezero only what 
mode you currently in.  If you press one of these hot 
keys from the Master Mode it will rezero all the modes 
however.  

It should be noted that if you are using an interface to 
your encoders without an IRQ (interrupt) and you are 
in any other screen besides the encoder reader 
screen and one of the encoders moves, the program 
will not see it move.  This is not true with an IRQ 
interface though.

You may setup any three of the encoders to read as a 
rotary readout to use in indexing.  From the encode 
reader screen press the 'r' key.  The program will ask 
you for what axis you would like setup as rotary.   In 
the Rotary Settings screen the options are:

ROTARY COUNTING   ON/OFF
Shut this off to go back to linear counting.

RESET TO ZERO
Reset the encoder to zero.

CURRENT VALUE       
Enter in the current degrees value.  Either decimal or 
in degrees, minutes, secs.

DISPLAY           
Display in degrees, minutes, secs or in decimal 
degrees.

NUM. IN 360 DEGREES    
Enter in the number of counts per rev. of your 
encoder times four because DRO reads the 
quadrature.

SHOW REVOLUTIONS   
Toggles between showing how many times past 360 
was hit.

COUNT DIRECTION   -/+
Change direction of counting up or down.

After entering in the data press ESC to return to the 
encode reader screen.

There is one other hot key that is not shown on the 
encoder reader screen and that is the 'h' Help key. 


Lindsay Engraving Inc. welcomes any feed back on 
this program.  

slindsay@nyx.cs.du.edu

Lindsay Engraving Inc.
3714 West Cedar Hills Drive
Kearney, NE 68847

