Maple Systems OIT Family - Manual (Page 34)

To upload a recipe using the OIT keypad:
1. Display the Recipe Screen using a pre-programmed key or from a screen request by the
PLC.
2. The recipe ‘initiator’ is only used for download purposes. Therefore, you must
configure a screen-dependent function key to upload the recipe.
3. To upload using a screen-dependent function key, simply press the function key when
the recipe is displayed. It is not necessary to change the recipe initiator. If the recipe
screen is not already displayed, pressing the screen dependent function key will
display and upload the recipe. See section “Screen Dependent Function Keys” in
Chapter 5: Key types on how to program the key to upload a recipe.
4. During upload, the OIT first sets the gate coil to the ‘on’ state to indicate that an
upload is in progress.
5. The OIT reads the preset values that currently reside in the predefined PLC registers
and stores these values in the OIT.
6. After all preset values are read from the PLC, the OIT signals the PLC that the recipe
has finished uploading by setting the gate coil back to the ‘off’ state.
To upload a recipe using the Message Request Register (MRR):
1. The PLC can start the upload of a recipe by simply placing the screen number
associated with that screen in the Message Request Register, (see “PLC Screen
Request” section in Chapter 5: Displaying Stored Screens for more information about
the Message Request Register). To get the OIT to upload the recipe, add +2000 to
the screen number before placing it into the MRR.
2. The OIT will read the MRR and display the recipe..
3. The OIT will automatically upload the recipe.
4. The recipe screen will remain on the OIT display until another screen is requested.
5. To download using a screen-dependent function key, press the function key when the recipe is
For example, a plastics factory makes three kinds of polyethylene bags. Each kind of bag
has unique characteristics:
Since these parameters will usually not be changed, the system programmer configures
them as preset ingredients in three separate recipe screens. (The Preset value can be
changed at runtime – see chapter 4: PLC Register Monitors.) The OIT operator does need
the ability to specify the number of bags to make in each run. So the system programmer
configures a PLC Register Monitor in each recipe screen to store this information. In this
scenario, the recipe screen for Bag A might look like the following screen.
Stored Screens 34
1010-0099, Rev. 07
Length Width Thickness Shape Color
Bag A
Bag B
Bag C
11"
15"
10"
8.5"
4"
10"
3 mm
2 mm
1 mm
fold top
sealed top
rounded
clear
black
green