VXI VT1422A - Manual (Page 144)

142 Programming the VT1422A for Data Acquisition and Control Chapter 4
Using the Status System
The VT1422A’s Status System allows for the quick polling a single register
(the Status Byte) to see if any internal conditions require attention.
Figure 4-9 shows that the three Status Groups (Operation Status,
Questionable Data and the Standard Event Groups) and the Output Queue
all send summary information to the Status Byte. By this method, the Status
Byte can report many more events than its eight bits would otherwise allow.
Figure 4-10 shows the Status System in detail.
Questionable Data Group
Operation Status Group
Standard Event Group
Status Byte
group summary bits
read with
*STB?
Output
Queue
Figure 4-9. Simplified Status System Diagram