Rosemount TankRadar Rex DAU 2100, Service Manual

Page: 91 / 154

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Rosemount Tank Radar Rex
Chapter 4 Service
Service Manual
308012En, Ed.2
May 2013
The location of the Field bus and Group bus connections are shown in
Figure 4-20.
Figure 4-20. The location of Field and Group bus connections on the
FCP board.
The microprocessor of the FCU is the 80C188. It contains a DMA
controller (Direct Memory Access) which allows the processor to process
other information while the DMA controls data between the RAM
memory and the serial ports.
There is RAM (Random Access Memory) of 32 KB for the data buffer.
The data buffer is used to store the information from the slave units. The
EPROM is used to store the program. When exchanging the EPROM it is
strongly recommended that the FCP board is removed from the FCU box
for better access of the memory chip.
The EEPROM is used to store database registers and can be remotely
reprogrammed (if the write protection switch is in the write enable
position).
There are three dual channel Serial Communication Controllers (SCC)
that control the six serial communication ports for Group Bus and Field
Bus communication.
Field Bus 1Field Bus 2Field Bus 3 Field Bus 4
Group Bus 1
Group Bus 2