Illegal Master Addresses - Allen-Bradley A-B QUALITY DL20 Series User Manual

Selecting a Master Address
The addressable master option allows you to connect up to 32 DL20s on a
single RS-422 network (up to 100 with inline repeaters). You can trigger
messages at one or all of the DL20s by sending a master address with the
message number. Refer to Chapter 5 for a description of addressable master
protocol.
The prompt for setting a MASTER ADDRESS looks like this:
If you answer Yes to this prompt, the DL20 will display:
You can now enter the master address. Some values are illegal addresses,
Table 8.D lists them:
Table 8.D

Illegal Master Addresses

Decimal
4
6
7
13
18
20
22
43
45
48 through 57
A master address of 0 disables the master address feature.
Note: Address 127 is recognized by all masters, regardless of the master
address. Use this a convenient means of triggering a message to all master
displays.
Note: A master address can also be selected using the Addressing Bar
(Catalog No. 2706-NF1) at the parallel port. This method does not require a
keyboard or terminal and is useful if you are downloading messages from a
tape. The Addressing Bar can only be used if communication to the display
is through the serial port.
Chapter 8
Special Functions
SET MASTER ADDR? N
MASTER ADDRESS: 0
Hex
04
06
07
0D
12
14
16
2B
2D
30 through 39
ASCII Character
EOT (CTRL D)
ACK (CTRL F)
BEL (CTRL G)
CR
DC2 (CTRL R)
DC4 (CTRL T)
SYN (CTRL V)
+
-
0 through 9
8–21