S.B.C. Elettronica S.p.A. - Engineering Division
HPDxxN – High Power User’s Manual
64
Example 10: Inter-Drive Communication
IDC (Inter Drive Communication) refers to a specific configuration of the serial port of the HPD
N drive that makes it possible to interchange parameters between two or more units.
With IDC enabled (Pr26=10) if bit b99.5 is set to 1 the HPD N activates a broadcast command
by sending the value of Pr81 to the address of Pr80. HPD Ns that receive broadcast commands
with Pr26=10 automatically set b99.5 to 1 causing automatic transmission of Pr81 to the address of
Pr80 in broadcast mode. Using this potential, it is extremely simple to connect two HPD N drives in
a loop via the serial ports, and a short program on the internal PLC will suffice to start transmission
at power-on and restore it in the event of communication errors. The following example describes
the PLC program required to copy Pr81 from the two drives in parameters Pr80.
Connection
function
These PLC instructions must be entered on only one of the drives; both drives must have
parameter Pr26=10 to enable the IDC function.
drive 1
drive 2
Pr81
Pr80
Pr80
Pr81
1
2
3
4
5
6
7
8
1
2
3
4
5
6
7
8
X5
X5
drive 1
drive 2
If broadcast is received
timer is set to 30mS
if time-out is present
reset serial comms
and set timer
LD
99.5
DIV
75.74.92
LD
99.0
SET
99.5
DIV
75.74.92
DIV
99.5
75 74 92
99.0
SET
99.5
DIV
75 74 92
