25/08/2004 ©
Söring
Service-Manual Arco- and RF-units
1
not valid for A-3000/ -2000
2
not valid for Arco-2000
-28-
3
not valid for MBC600
4
not valid for Arco-1000
4. Description of front panel
4.1. General description
The front panel contains the push-buttons and switches necessary to operate the
equipment and displays the actually selected values. Furthermore relevant information
regarding safety and function is displayed. The front panel is composed of different panel
modules. Depending on type of equipment the number varies between 3 and 5 modules.
The indicators of the panel are controlled via the I
2
C-bus. (As an exception the LED's for
Output-power error and Function error are controlled via parallel data lines.)
4
Keyboard scanning is also done via the I
2
C-bus. The suppression of key bouncing is
done by the CPU.
The panel gets its supply-current alternatively from the CPU-connection or from a
connection to the low-voltage supply.
4.2. Connection to other units
4.2.1. Connection to CPU
The front panel is connected to the CPU by the I
2
C-bus. The initiative for a data transfer
is exclusively taken by the CPU.
4.2.2. Connection to low-voltage supply
In order to avoid unnecessary loading of the CPU connection by high currents the
displays of the panel are fed from a separate power supply (5V). Furthermore the
connection of the CPU with the microprocessor monitoring of the power supply is carried
out via the front panel module "MA“ (Master).
