Agilent Technologies 8360B, User Manual, Page: 135 / 496

There may or may not b e a command to read a particular condition
register.
Transition Filter
The tr ansition lter sp ecies whic h t yp es of bit state c hanges in the
condition register will set corresp onding bits in the ev en t register.
T ransition lter bits may b e set for p ositiv e transitions ( PTR ),
negative transitions ( NTR ), or b oth. P ositive means a condition
bit c hanges from 0 to 1. Negative means a condition bit c hanges
from 1 to 0. T ransition lters are read-write. T ransition lters
are unaected b y *CLS (clear status) or queries. They are set to
instrumen t dep enden t v alues at p o w er on and after *RST .
Ev ent Register
The event r e gister latches transition ev en ts from the condition
register, as sp ecied b y the transition lter. Bits in the ev en t register
are latched, and once set they remain set un til cleared b y a query or
a *CLS (clear status). There is no buering, so while an ev en t bit is
set, subsequen t ev en ts corresp onding to that bit are ignored. Ev en t
registers are read-only .
Enable Register
The enable r e gister sp ecies the bits in the ev en t register that
can generate a summary bit. The instrumen t logically ANDs
corresp onding bits in the ev en t and enable registers, and ORs 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 do es not aect it. There is alwa ys a
command to read and write to the enable register of a particular
status group.
An Example Sequence
Figure 1-34 illustrates the resp onse of a single bit p osition in a
t ypical status group for v arious settings. The c hanging state of the
condition in question is sho wn at the b ottom of the gure. A small
binary table sho ws the state of the c hosen bit in eac h status register
at the selected times T1 to T5.
Getting Started Programming 1-107