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SHEETDESCRIPTIONDESIGN DATE EDIT
01 Mutai Newl
re
istered
TITLE: Additional explanation of
PROFIBUS-DP Master function
(I/O Module Assignment function)
B-62924EN/04-1
FANUC LTD.
02.10.7
DRAW.NO.
When both the master and slave functions are used together
In this case, the data refresh time is similar to that described in "When only the master
function is used" above.
However, SIZE: DI/DO data size in expression (A) is as follows:
SIZE = SIZE
mas
+ SIZE
slv
SIZE
mas
: DI/DO data size for the master function
SIZE
slv
: DI/DO data size for the slave function
Example of calculating the data refresh time
[Conditions]
• CNC model: 16i/18i/21i-A/B
• Communication slave station settings for the master function :
- Slave No. 3: N_slot=1, SIZE = 122/122
- Slave No. 4: N_slot=1, SIZE = 122/122
- Slave No. 5: N_slot=1, SIZE = 122/122
- Slave No. 6: N_slot=1, SIZE = 122/122
• Settings for the slave function : DI/DO SIZE = 8/8
[Calculation]
• First group
- Calculation for slave No. 3 and 4:
37×2 + 8.6×(1+1) + 1.3×(244+244+16)=746 <750
→ N_slave, N_slot and SIZE indicate the maximum values.
Slave No 3 and 4 are first group.
- Calculation for slave No. 3 to 5:
37×3 + 8.6×(1+1+1) + 1.3×(244+244+244+16)=1109 >750
→ The values of N_slave, N_slot and SIZE should be cleared.
• Second group
- Calculation for slave No. 5 to 6:
37×2 + 8.6×(1+1) + 1.3×(244+244+16)=746 <750
→ Slave No 5 and 6 are second group and calculation for all
communication slave stations is complete. Thus slave group
(n) is determined to be 2.
Thus, the data refresh time is 16 msec for this example.