Each digital input or output signal is specified by a “signal number”. When configuring a controller, some functions require the specification of a signal. This is typically accomplished by entering a signal number via a web-based form. If a signal number of zero is specified, this indicates that no signal is to be used. If a negative signal number is entered, the logical on/off sense of the signal value is inverted. Signal numbers are also used by the Signal class in GPL procedures.
Signal numbers are organized into ranges based on the signal type. Within those ranges, the signals are organized into banks of 96 I/O points. The bank numbers start at 0. A signal number is formed by adding the signal base value to 100 times the bank number.
In a distributed servo network, general digital I/O signals on the slave controllers may be accessed from the master controller by adding 100000 times the slave controller node number to the signal number. The first slave controller has a node number of 2. Therefore, add 200000 to a signal number in order to access the first slave controller's general digital I/O signals. However, dedicated inputs and outputs on a slave controller cannot be accessed from the master controller.
The table below shows the possible signal numbers based on the type and the bank.
| Signal Type | Signal Base | Signal Range | Banks |
|---|---|---|---|
|
None |
0 |
0 |
|
|
General outputs |
1 |
1 + 100*bank |
0 = Local outputs,
|
|
Dedicated outputs |
8001 |
8001 + 100*bank |
0 = Controller outputs, |
|
General inputs |
10001 |
10001 + 100*bank |
0 = Local inputs, |
|
Dedicated inputs |
18001 |
18001 + 100*bank |
0 = Controller inputs, |
|
Software I/O |
20001 |
20001 - 20064 |
Not used |
|
Servo Network node n general |
100000*n + 13 |
100000*n + 20 |
0 = Local outputs only |
|
Servo Network node n general |
100000*n + 10001 |
100000*n + 10012 |
0 = Local inputs only |
|
Servo Network node n dedicated inputs and outputs |
|
|
Cannot be accessed by master controller |