2
Siemens Building Technologies
Cerberus Division
e1148c
06.2000
2
Product description
2.1
The CPU board
The CPU board (Fig. 1) is the only board that composes the Cerban Splitter CBS-3.
Neuron
Chip
Flash EPROM
RAM
CPU
RTC
UART
UART
Reset
Service
UART1
UART2
UART3
UART4
RX
TX
RX
TX
RX
TX
RX
TX
service pin LED
Diagnostic
S3
S4
S2
S1
1 2
8
7
6
4
3
5
8
7
6
4
3
2
1
5
8
7
6
4
3
2
1
5
2
8
7
6
4
3
5
NC
Fig. 1 The CPU board
On this board there are:
§
the CPU, the RAM and Flash EPROM
§
the Real Time Clock (RTC)
§
two UART chips, that manage the four GW-21 serial lines
§
the Neuron Chip, that lets the GW-21 to communicate with the LonWork network
§
four dip switch blocks (S1 - S4), used to configure the GW-21 as described later
§
one reset push-button, used to reset the board
§
one service push-button, to send the service signal to the Neuron Chip
§
four sets of two LEDs. These LEDs show the status of UART RX/TX lines.
§
three LEDs used for diagnostic purposes.
