User`s manual
16 Motionnet Master-Slave Motion System
PCI-7856
User’s Manual
RAM usage, users are able to write data into a FIFO in the central
device, and issue a send command using the same method. This
communication will be sent and received automatically by inter-
rupting the cyclic communication. A complete command delivering
time depends on the number of MNET packets. One packet com-
mand can be delivered in one MNET scan (cycle) time.
Command Delivery
For command delivery procedures which are transferred, in a
cyclic communication, the time allowed for communication by a
single module is fixed. However, in a data communication, the
communication time will vary, depending on how the communica-
tion is controlled by the user's program and the time needed to
access the PCI-7856. We will skip these elements and simply cal-
culate the basic data communication time in this section.
64(max)
4
Interrupt
Cycliccommunicat i on
1
2
3
5
S
end Response
Tot alofsendandreceive:4bytes
Datacommunication
Communicat ionsequenceimage
(Send, Receive)
Cente
r
L
ocal Local Center