5 mstr global read example – Toshiba ICC MBP-100 User Manual

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Address Value

40200

Value to write to register 1 @ network address 32

40201

Value to write to register 2 @ network address 32

40202

Value to write to register 3 @ network address 32

40203

Value to write to register 4 @ network address 32

4. In this case, we are accessing four registers, so set the bottom portion of

the MSTR instruction (“number of registers”) to 4. In the case of MSTR
writes, this number cannot be greater than 100 by definition.

5. Initiate the write command by closing internal relay 1. The data at registers

40200, 40201, 40202, and 40203 will be written to registers 1, 2, 3 and 4,
respectively, of the MBP-100 located at network address 32.


15.5 MSTR Global Read Example

The following example demonstrates how to use the MSTR instruction to read
32 words of global data from an MBP-100 located at Modbus Plus network
address 10.

1. Set up a ladder logic program as shown in Figure 37.

2. Set the top portion of the MSTR Instruction to 40070. This will be the

starting address of the MSTR Control Block. Set the control block registers
to the following values:

Address Description Register

Value

40070

MSTR function (global read)

6

40071

Error code

Read Only

40072

Number of consecutive registers to read

32

40073

Number of words available to read

Read Only

40074

Destination node address

10

40075

Master node address

1

3. Set the middle portion of the MSTR instruction to 40300. This will be the

starting address of the MSTR data area. This is the location that will
contain the data returned from the MSTR global data read transaction.

Address Value

40300

Value at offset 0 in global data from network address 10

40301

Value at offset 1 in global data from network address 10

: :

40300+n Value at offset n in global data from network address 10

: :

40331

Value at offset 31 in global data from network address 10

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