Thunder Scientific series 3900, Operation And Maintenance Manual

Page: 123 / 164

3900 Serial I/O Page 12
?ER
Read Error Number
Description
Returns the current error number relating to system shutdown.
Prerequisites
None
Syntax
?ER
Parameters
None
Remarks
Data Returned
?ER
returns one of several values indicating the reason(s) that the
system shut down. The value returned can be any one, or an algebraic
combination, of several, of the following:
VALUE DESCRIPTION
0 No Error
1 Expansion Valve Not Closing
2 Flow Valve Not Closing
4 Low Supply Pressure
8 Cabinet Temperature Overrange
32 Reference Temperature Underrange
48 Reference Temperature Overrange
64 Test Temperature Underrange
80 Test Temperature Overrange
128 Saturation Temperature Underrange
144 Saturation Temperature Overrange
512 Test Pressure Underrange
768 Test Pressure Overrange
1024 Low Range Saturation Pressure Underrange
1280 Low Range Saturation Pressure Overrange
2048 High Range Saturation Pressure Underrange
2304 High Range Saturation Pressure Overrange
Examples
After an unexpected system shutdown (indicated by the value returned
from the
?RU
command or the last parameter in the ? command), the
?ER
command is used to determine the nature of the failure:
computer sends
?ER
<CR>
3900 responds
4
<CR><LF>
The "4" returned indicates that the system shutdown due to a low
supply pressure.
See Also
?, ?RU