Siemens SIMATIC S5-90U System Manual page 126

Addressing and Access to I/Os
Digital Modules with more than Eight Channels
0
Slot No.
64.0 to 64.7
PLC
65.0 to 65.7
Figure 6-7. Address Assignments for Digital Modules with more than Eight Channels
Each channel of a digital module is represented by one bit. Each bit must therefore be assigned a
separate number. A channel is thus addressed in the following manner:
The address "X.Y" is composed of the following:
Byte Address X
The byte address is derived from the number of the slot the module is plugged into and the
connection of the actuators and sensors to the terminals of the module's front connector.
Bit Address Y (Channel Number Y)
The bit address is derived from the connection of the actuators and sensors to the terminals of the
front connector.
The assignment of channel number to terminal number is printed on the module's front panel.
Example: A digital input module 6ES5 422-8MA11 is plugged into slot 1, a sensor is connected to
terminal 13, i.e. the channel number is 1. The address is therefore 72.1. For
assignments of front connector terminals to channel numbers refer to the illustration of
the module in Section 15.5.1.
6-6
1
72.0 to 72.7
73.0 to 73.7
x . y
Figure 6-8. Structure of a Digital Address
7
120.0 to 120.7
121.0 to 121.7
Bit address (channel number)
Byte address
EWA 4NEB 812 6115-02b
S5-90U/S5-95U
The following
slots are not
available for
digital modules
with more than
eight channels