C.6 Communications Timing - YASKAWA U1000 iQpump MATRIX Drive User Manual

C.6 Communications Timing

C.6 Communications Timing
To prevent a communications overrun in the slave drive, the master should wait a certain time between sending messages to
the same drive. In the same way, the slave drive must wait before sending response messages to prevent an overrun in the
master. This section explains the message timing.
u
Command Messages from Master to Drive
The master must wait for a specified time between receiving a response and resending the same type of command to the same
slave drive to prevent overrun and data loss. The minimum wait time depends on the command as shown in
Command Type
• Control command (Run, Stop)
1 • Set inputs/outputs
• Read monitors and parameter values
2 Write parameters
3 Save changes using an Enter command
4 Enter with storage to drive EEPROM after initialization
<1> If the drive receives command type 1 data during the minimum wait time, it will perform the command and then respond. However, if it receives
a command type 2 or 3 during that time, either a communication error will result or the command will be ignored.
Set a timer in the master to check how long it takes for the slave drive(s) to respond to the master. If no response is received
within a certain amount of time, the master should try resending the message.
u
Response Messages from Drive to Master
If the drive receives a command from the master, it will process the data received and wait for the time set in H5-06 until it
responds. Increase H5-06 if the drive response causes overrun in the master.
382
Table C.3 Minimum Wait Time for Sending Messages
Example
PLC→Drive
Command message Response message
Figure C.6 Minimum Wait Time for Sending Messages
PLC→Drive
Command message Response message
H5-06
24 bit length
setting
Figure C.7 Minimum Response Wait Time
YASKAWA TOEPYAIUPW01A YASKAWA AC Drive - U1000 iQpump Matrix Drive User Manual
Drive→PLC PLC→Drive
Command message
Master Send
24 bit length
Wait Time
Drive→PLC PLC→Drive
Command message
Table C.3.
Minimum
Wait Time
<1>
5 ms
H5-11 = 0: 50 ms
<1>
H5-11 = 1: 200 ms
200 ms to 2 s, depending on the
number of parameters that
<1>
were changed
5 s
Time
Time