Specifications
Engineering Standard –NSW
Signalling SMS 02
Cerberus Level Crossing Monitor Equipment
March 2005 Version 1.2 © Australian Rail Track Corporation Page 27 of 118
This document is uncontrolled when printed.
2. If serial port A transmit interrupt then if there are characters to
transmit, send the next one, otherwise clear the interrupt.
3. If serial port A external status interrupt then turn on led 6 and check
the state of carrier detect. If it is on, set the port A communications
link flag, and enable RTS, CTS flow control. If it is off, clear the port
A communications link flag, store the connection lost time, and
disable RTS, CTS flow control. Reset the external status interrupt.
4. If a serial port B receive interrupt occurred then turn led 5 on, check
for and process any reception errors, and process the received
character.
5. If serial port B transmit interrupt then if there are characters to
transmit, send the next one, otherwise clear the interrupt.
6. If serial port B external status interrupt then turn on led 6 and check
the state of carrier detect. If it is on, set the port B communications
link flag, and enable RTS, CTS flow control. If it is off, clear the port
B communications link flag, store the connection lost time, and
disable RTS, CTS flow control. Reset the external status interrupt.
Else if their has been no serial port interrupt for 1 second, then check
the transmission/reception state for each serial port and if they are not
idle take the necessary corrective action.
3.2.2.4 Configuration & Set-Up
A specific EPROM is prepared and labelled for the particular level
crossing. The EPROM is inserted in U5. The EPROM must be type
27512 running at 200nS or better.
A DALLAS DS1235YWL 200nS or better is inserted in U6. A DALLAS
DS1244Y 200nS or better is inserted in U7.
The links for the board must as follows (all others shall be open circuit,
that is removed):
1
-
2
3
-
4
5
-
6
7
-
8
10
-
11
12
-
13
17
-
18
19-20 25-26 27-28 29-30 31-32 33-34 37-38
39
-
40
43
-
44
47
-
48
49
-
50
51
-
52
53
-
54
55
-
56
59
-
6
0
85
-
86
87
-
88
89
-
90
95
-
96
105
-
106
107
-
108
Drawing M08-781 SCADA-2000 A/2.0 I/O Board jumper allocations
(marked up for LX monitor) shows the location and setting of the links.
3.2.2.5 Troubleshooting
Check the LED indications on the I/O Board for correct operation (see
section above).
Check 5 volt supply is greater than 4.75 volts and less than 5.25 volts. It
is easiest to check this on the input or output Optoisolator board test
pins.