Lenze SMVector RS-485 LECOM - Manual (Page 19)

17 CMVLC401A
Commissioning
6.4 Broadcast / Multicast
In a bus network, the command BROADCAST is to address all devices or a group of devices (multicast) at the same
time. The structure of the BROADCAST telegram is similar to the structure of the SEND telegram. The only exception is
that it does not return an acknowledgement.
The devices can be selected via their controller addresses. The controller addresses listed in Table 8 are reserved for
a BROADCAST telegram.
Table 8: Controller Addresses for Broadcast Telegram
Controller address
(reserved)
Controller address
of groups
ASCII character
AD1 AD2
00 all “0” “0”
10 11 to 19 “1” “0”
20 21 to 29 “2” “0”
30 31 to 39 “3” “0”
40 41 to 49 “4” “0”
50 51 to 59 “5” “0”
60 61 to 69 “6” “0”
70 71 to 79 “7” “0”
80 81 to 89 “8” “0”
90 91 to 99 “9” “0”
Example for a BROADCAST telegram:
All controllers are to be stopped when setting controller enable (code number C40 = 0).
The host sends the following BROADCAST telegram:
EOT 0 0 STX 4 0 0 ETX BCC
The controllers do not return an acknowledgement.
Monitoring of the slave response:
The master monitors the selected slave. The slave must return a response within a defined time. Under the following
circumstances the slave does not return a response to the master (time out):
• The controller address could not be recognized
• The transmission path is faulty
• A BROADCAST telegram had been sent.
• The hardware does not work properly
If the master does not receive a response within a defined period of time, the transmission is tried again. The number
of repetitions is limited.
The monitoring time in the master should be approx. twice as long as the maximum response time.
Transmission faults
After a transmission fault, the master can read C0068 and evaluate the communication error in bit 4... 7.