240
Data Memory (DM) Allocation Section 7-4
Communications Control Bits (Offset: +3, +4, +5, and +6)
Note There are restrictions on the number of times data can be written to the Tem-
perature Controller’s non-volatile memory. When frequently sending data to a
Temperature Controller, either set the Write Command Bit to 0 after writing is
completed, or set the write mode for the Temperature Controller to RAM write
mode. Also, execute commands to select the RAM write mode and backup
mode in only one scan. Some devices will write to non-volatile memory each
time the modes are selected, and the life of the non-volatile memory will be
exhausted much more quickly if selections are made every scan.
Bit Offset +3
(Units 0 to 7)
Offset +4
(Units 8 to 15)
Offset +5
(Units 16 to 23)
Offset +6
(Units 24 to 31)
0 Unit 7 Read Command Bit Unit 15 Read Command Bit Unit 23 Read Command Bit Unit 31 Read Command Bit
1 Unit 7 Write Command Bit Unit 15 Write Command Bit Unit 23 Write Command Bit Unit 31 Write Command Bit
2 Unit 6 Read Command Bit Unit 14 Read Command Bit Unit 22 Read Command Bit Unit 30 Read Command Bit
3 Unit 6 Write Command Bit Unit 14 Write Command Bit Unit 22 Write Command Bit Unit 30 Write Command Bit
4 Unit 5 Read Command Bit Unit 13 Read Command Bit Unit 21 Read Command Bit Unit 29 Read Command Bit
5 Unit 5 Write Command Bit Unit 13 Write Command Bit Unit 21 Write Command Bit Unit 29 Write Command Bit
6 Unit 4 Read Command Bit Unit 12 Read Command Bit Unit 20 Read Command Bit Unit 28 Read Command Bit
7 Unit 4 Write Command Bit Unit 12 Write Command Bit Unit 20 Write Command Bit Unit 28 Write Command Bit
8 Unit 3 Read Command Bit Unit 11 Read Command Bit Unit 19 Read Command Bit Unit 27 Read Command Bit
9 Unit 3 Write Command Bit Unit 11 Write Command Bit Unit 19 Write Command Bit Unit 27 Write Command Bit
10 Unit 2 Read Command Bit Unit 10 Read Command Bit Unit 18 Read Command Bit Unit 26 Read Command Bit
11 Unit 2 Write Command Bit Unit 10 Write Command Bit Unit 18 Write Command Bit Unit 26 Write Command Bit
12 Unit 1 Read Command Bit Unit 9 Read Command Bit Unit 17 Read Command Bit Unit 25 Read Command Bit
13 Unit 1 Write Command Bit Unit 9 Write Command Bit Unit 17 Write Command Bit Unit 25 Write Command Bit
14 Unit 0 Read Command Bit Unit 8 Read Command Bit Unit 16 Read Command Bit Unit 24 Read Command Bit
15 Unit 0 Write Command Bit Unit 8 Write Command Bit Unit 16 Write Command Bit Unit 24 Write Command Bit
Bit Range Function
Write Com-
mand Bit
0: Writing prohibited
1: Writing allowed
Setting this bit to 1 allows operation commands and data writes to the component
with the corresponding unit number. Data is not written when this bit is set to 0.
When an error occurs while writing data, the appropriate error code is written to
the write data area’s response monitor area. (See Response Monitor Area on
page 248 for details.)
Read Com-
mand Bit
0: Reading prohibited
1: Reading allowed
Setting this bit to 1 allows data to be read from the component with the corre-
sponding unit number. Data is not read when this bit is set to 0.
When an error occurs while reading data, the appropriate error code is written to
the read data area’s response monitor area. (See Response Monitor Area on
page 246 for details.)