Condition Registers; Transition Filters - Keithley 6517A User Manual

IEEE-488 Reference
OR
To Questionable
Summary Bit
(QSB) of Status
Byte Register
(See Figure 3-13).
Figure 3-12
Questionable event status

3.8.1 Condition registers

As shown in the illustrations, all status register sets, except
the standard event status register set, have a condition regis-
ter. A condition register is a real-time read-only register that
constantly updates to reflect the current operating conditions
of the instrument. For example, while a calculation is being
performed, bit B9 (Calc) of the Operation Condition Regis-
ter is set. When the calculation is completed, bit B9 clears.
The :CONDition? query commands in the STATus Sub-
system are used to read the condition registers. See para-
graph 3.20 for details.
3.8.2 Transition filters
As shown in the illustrations, all status register sets, except
the standard event status register set, have a transition filter.
A transition filter is made up of two registers that are pro-
grammed by the user. It is used to specify which transition (0
to 1, or 1 to 0) in the corresponding condition register will set
the corresponding bit in the event register.
3-14
Always Warn Seq Coul Ohms
Zero
(B15) (B14) (B13) (B12) (B11) (B10)
0
Always
Warn Seq Coul Ohms
Zero
(B15) (B14) (B13) (B12) (B11) (B10)
0
Always
Warn Seq Coul Ohms
Zero
(B15) (B14) (B13) (B12) (B11) (B10)
0
&
&
&
&
&
Warn Seq Coul Ohms
(B15) (B14) (B13) (B12) (B11) (B10)
Warn = Command Warning
Cal = Calibration Summary
Seq = Sequence Test Summary Temp = Temperature Summary
Coul = Coulombs Summary Amp = Amps Summary
Ohm = Ohms Summary
Volt = Volts Summary
Hum = Humidity Summary
Hum Cal Temp
(B9) (B8) (B7 - B5) (B4) (B3)
Hum Cal Temp
(B9) (B8) (B7 - B5) (B4) (B3)
Hum Cal Temp
(B9) (B8) (B7 - B5) (B4) (B3)
&
&
&
Temp
Hum Cal
(B9) (B8) (B7 - B5) (B4) (B3)
& = Logical AND
OR = Logical OR
PTR = Positive Transition Register
NTR = Negative Transition Register
A filter can be programmed for positive transitions (PTR),
negative transitions (NTR) or both. When an event is pro-
grammed for a positive transition, the corresponding bit in
the event register sets when the corresponding bit in the con-
dition register changes for 0 to 1. Conversely, when pro-
grammed for a negative transition, the bit in the event register
sets when the corresponding bit in the condition register
changes from 1 to 0.
The :PTR and :NTR commands in the Status Subsystem are
used to set or clear the individual bits of the transition filter
registers, while the :PTR? and :NTR? query commands are
used to read the registers (see paragraph 3.20 for details).
Reading a transition filter register does not affect its bit pat-
tern.
The following operations set (1) all bits of all PTR registers
and clear (0) all bits of all NTR registers:
• Cycling power
• Sending :STATus:PRESet
Amp Volt Questionable
Condition
(B2) (B1) (B0) Register
Amp Volt
PTR Questionable
Transition
(B2) (B1) (B0)
NTR Filter
Amp Volt
Questionable
Event
(B2) (B1) (B0)
Register
&
&
Questionable
Amp Volt
Event Enable
(B2) (B1) (B0) Register