Maple Systems OIT Family - Manual (Page 9)

The MRR is a data register in the PLC that allows the PLC to request screens for display
on the OIT. The OIT writes a zero to the MRR on initialization and reads the MRR every
200 msec. For more information on the MRR, refer to the Message Request Register
section in CHAPTER 2: Operational Overview.
10. In the Message Request Register group box, in the scroll box, specify the PLC
address for the MRR.
The Screen Stack stores PLC screen requests in a stack. This allows the OIT operator to
view the screens using the Next Message and Last Message keys. When the Screen Stack
is used, no screens are displayed on the OIT until the Next Message or Last Message
keys are pressed. For more information on the Screen Stack, refer to the Screen Stack
section in CHAPTER 5: Displaying Stored Screens. For this sample project, we will
disable the Screen Stack.
11. To disable the Screen Stack, in the Message Request Register group box, if the
Enable Message Stack check box is checked, select the Message Stack check box to
remove the check.
The CMR is a data register in the PLC that allows the PLC to determine which screen the
OIT is displaying. The OIT writes the current screen number to the CMR whenever the
screen changes. For more information on the CMR, refer to the Current Message Register
section in CHAPTER 2: Operational Overview. For this sample project, we will enable
the CMR and specify a PLC address.
12. To enable the CMR, in the Current Message Register group box, select the Enable?
check box.
13. In the Current Message Register group box, in the scroll box, specify the PLC address
for the CMR.
The MRR and CMR can be configured to use decimal or BCD format.
14. Specify the data format for the MRR and CMR.
• To use decimal format, in the MRR/CMR Data Format group box, select the Use Decimal For-
mat for Data option button.
• To use BCD format, in the MRR/CMR Data Format group box, select the Use BCD Format
for Data option button.
15. Choose the Done button to return to the OIT - Controller Settings dialog box.
16. Choose the Done button to return to the OITware-200 main screen.
Getting Started 9
1010-0099, Rev. 07
OIT3100 and OIT4100 Series
These OIT models allow the MRR to be disabled. For this sample project, we will
enable the MRR.
1. To enable the MRR, in the Message Request Register group box, if the Enable
check box is not checked, select the Enable check box.
These OIT models allow you to configure up to 32 “bit position” or “value” MRRs.
“Bit position” MRRs allow the PLC to request a screen by setting a bit instead of
writing a number. For this sample project, we will use a single “value” MRR. For
more information on using multiple or “bit position” MRRs, refer to the PLC Screen
Request section in CHAPTER 5: Displaying Stored Screens.
2. To disable the Enhanced Features, in the Message Request Register group box, if
the Use Enhanced Features check box is checked, select the Use Enhanced
Features check box to remove the check.