AtlasPC Digital Control, Vol. I
Manual 85586V1
58
Woodward
•
The serial ports are individually isolated from each other, and from the rest
of the AtlasPC control. The RS-422 and RS-485 specifications state that a
ground wire is needed if there is no other ground path between units. The
preferred method for isolated ports is to include a separate wire in the
ground cable that connects the circuit grounds together.
•
Non-isolated nodes may not have a signal ground available. If signal ground
is not available, use the alternate wiring scheme of connecting all circuit
grounds of isolated nodes to the shield, and connecting the shield to earth
ground at a non-isolated node.
Fault Detection (Board Hardware)
Each SmartCore board has a red fault LED that is turned on when the system is
reset. During initialization of a board, which occurs after every CPU reset, the
CPU turns the Fault LED on. The CPU then tests the board using diagnostic
routines built into the software. If the diagnostic test is not passed, the LED
remains on or blinks. If the test is successful, the LED goes off. If the fault LED
on a board is illuminated after the diagnostics and initialization have been
completed, the SmartCore board may be faulty.
Number of LED Flashes
Failure
1
Microprocessor
failure
2
Bus, address, any unexpected exception error
3
Failure during RAM test
4
Local
watchdog
timeout
5
Failure during EE test
6
Failure during FLASH programming or erasing
7
Kernel software watchdog count error
10
Failure during 68302 test
11
Failure during RTC test
12
TPU
RAM
Failure
20...
Operating system specific errors use 20 & above
Table 6-1. SmartCore Failure Codes
Fault Detection (I/O)
In addition to detecting board hardware faults, the application program may
detect I/O faults.
•
Analog Input Faults—The application software may set a high and low latch
set point to detect input faults.
•
Speed Sensor Input Faults—The application software may set a high and
low latch set point to detect input faults.
•
Serial Port Faults—The system monitors the serial communications on the
three serial ports, for various communication errors.
•
Microcontroller Faults—The system monitors a software watchdog, a
hardware watchdog, and a software watchdog on the PC/104 bus
communications. All outputs are shutdown in the event of a microcontroller
fault.
Summary of Contents for AtlasPC
Page 8: ...AtlasPC Digital Control Vol I Manual 85586V1 vi Woodward...
Page 130: ...AtlasPC Digital Control Vol I Manual 85586V1 122 Woodward...
Page 131: ......
Page 132: ......
Page 133: ......