Bosch CL300 - Page 118

SystemModules
FlexibleAutomation
4−66
Configuration To implement distributed expansion, the AG/DZ Expansion Module is
centrally installed in the basic unit, and the AG/DUs are remotely in
stalled in the expansion units.Distributed expansion requires the use of
the GG301/301−K Basic Unit.
A maximum of 2 expansion lines can be connected to each AG/DZ. Each
expansion line can contain up to 4 expansion stations, which in turn can
be expanded centrally and/or in parallel (see 2.1.12.3).
Function Communication between the expansion stations and the central proc
essing unit is handled by input and output images. These are contained
in the AG/DZ Expansion Module and are also maintained in the working
memory of the AG/DU module. The output image is written by the central
processing unit, read by the AG/DZ and transmitted to the AG/DU. The
input image is the reciprocal representation of the output image. The I/O
level can be accessed directly. For this purpose, the AG/DZ sends a
WAIT signal to the ZE.
PeripheralBus
WaitSignal
Processor
Input

Output
Input
Byte
Output
Error
Message
Data
Trans−
Func−
tional
Moni−
toring
ZE
Central
Proces−
Read
AG/DZ
Processor

Powersupplyfor
InternalOperating
AG/DU
Expansion
Unit
Output
Memory
Input
Memory
Input
Modules
Output
Modules
Voltages
Byte
Image
Image
sing
Unit
ZE
Write
ZE
Read
ZE
Write
ZE
fer
Data
Trans−
fer


Feed−
back
SystemBus
PeripheralBus
(BasicUnit)
Fig.4−36Function AG/DZ and AG/DU