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Contents
Chapter 4 — Programming Considerations
In the example we configured the Allen-Bradley device to use Datalink output words.
The MSTR 6 instruction (Read Global Data), when programmed in a Host PLC, will
retrieve the Global Data from the 1560-MBP and place it in the Host PLC register
space beginning at address 40510.
enable -
- active
- error
- success
abort -
Contents of registers in control block
40500 = 6 global read data instruction
40501 = 0 Error code
40502 = 10 length of the global data
40503 = 0 number of words available
40504 = 37 slave address to retrieve data from
40510 = Destination address for global data
from slave 37
MSTR
00010
Modicon Programming Example - MSTR Type 6
Please note that not all A-B Scanport devices
support Datalinks. In particular, the SMC Dialogue
Plus does not. To operate with the SMC Dialogue
Plus do not enable Datalink Messaging.
4.2.2 Host Issued Read Commands - MSTR Type 2
If the PLC Programmer does not want to use Global Data or if
there is a desire to read more data out of the 1560-MBP, the
MSTR Type 2 Read Command can be used. The MSTR Type 2
Read command has access to all available parameter values
(40101 to 40xxx), in addition to the Control and Status registers
(40001 to 40100).
MSTR Type 2 Accessible Data Registers: The memory map for the
registers which a PLC programmer can access from the 1560-MBP using
the MSTR Type 2 command.
Write Data – Control, Reference & Data Link IN
Read Data – Feedback & Data Link OUT
Miscellaneous data space
Used for MBP status data (See Section 4.3)
Parameter Register Space
This register space contains the parameter table from the
SCANport device. This paramaters are stored in their
numerical order (example):
40101 = Parameter #1
40102 = Parameter #2
The full length of this space is a function of the SCANport
device connected. Max size is 2000 parameters.
40001
40011
40021
40101
4xxxx
40510
40500
