HP (Hewlett-Packard) HP 8360 Benutzerhandbuch

There may or may not be a command to read a particular condition
register.

The 

specifies which types of bit state changes in the

condition register will set corresponding bits in the event register.
Transition filter bits may be set for positive transitions 
negative transitions 

or both. Positive means a condition

bit changes from 0 to 1. Negative means a condition bit changes
from 1 to 0. Transition filters are read-write. Transition filters
are unaffected by 

 (clear status) or queries. They are set to

instrument dependent values at power on and after 

The 

latches transition events from the condition

register, as specified by the transition filter. Bits in the event register
are latched, and once set they remain set until cleared by a query or
a 

 (clear status). There is no buffering, so while an event bit is

set, subsequent events corresponding to that bit are ignored. Event
registers are read-only.

The 

specifies the bits in the event register that

can generate a summary bit. The instrument logically 
corresponding bits in the event and enable registers, and 

 all

the resulting bits to obtain a summary bit. Summary bits are in
turn recorded in the Status Byte. Enable registers are read-write.
Querying an enable register does not affect it. There is always a
command to read and write to the enable register of a particular
status group.

Figure 

 illustrates the response of a single bit position in a

typical status group for various settings. The changing state of the
condition in question is shown at the bottom of the figure. A small
binary table shows the state of the chosen bit in each status register
at the selected times 

 to