PSI System Controls and Diagnostics
A500 User Manual
A500_UM_090115 Page 34 of 61
Boot
Reset
POST
Run
Fatal
Error
found
Success
Idle
A500:LoadProgram()
Load program
Success
Failed
Action
Started
Complete
Error
Error
detected
Go to Idle
command
Figure 19. A500 software base state machine
The present state is displayed on the bottom left of the A500 display (see section 12.3.1). The
states are described below:
State
Description
BOOT
POST successful, ready to accept either boot program or code download
command.
CONN
Application program successfully loaded, but devices attached to the FO
loops have not been successfully connected.
IDLE
All devices are connected and ready to accept commands.
RUN
Running an application command, pass-through not possible but other
commands may be accepted.
ERROR
Error detected while in the RUN state.
FATAL
Fatal hardware detected by POST, communication possible with the A500
device if the Ethernet did not fail, but no other functions allowed.
After a successful POST the boot-loader enters the BOOT state and automatically downloads the
host application stored in the FLASH program memory. Once the program is successfully
booted the state transitions to the Conn state, waiting for devices to be discovered by the host
and connected. A special Ethernet switch combination is provided that will cause the A500 to
stop at the Boot state. Setting the three switches each to 8 will enable this feature, and establish
the default Ethernet address 192.168.100.100.