Remote Commands
STATus Commands
74
Agilent
8169A
Polarization Controller, Second Edition
STATus Commands
There are two `nodes' in the status circuitry. The OPERation node shows
things that can happen during normal operation. The QUEStionable node
shows error conditions.
Each node of the status circuitry has five registers:
• A condition register (CONDition), which contains the current status. This
regis
ter is updated continuously. It is not changed by having its contents read.
• The event register (EVENt), which contains the output from the transition regis-
ters. The contents of this register are cleared when it is read.
• A positive transition register (PTRansition), which, when enabled, puts a 1 into
the event register, when the corresponding bit in the condition register goes
from 0 to 1.
The power-on condition for this register is for all the bits to be enabled.
• A negative transition register (NTRansition), which, when enabled, puts a 1 into
the event register, when the corresponding bit in the condition register goes
from 1 to 0.
The power-on condition for this register is for all the bits to be disabled.
• The enable register (ENABle), which enables changes in the event register to
affect the Status Byte.
The status registers for the polarization controller are organized as shown:
Figure 14 The Status Registers