R&S NRP2, Руководство пользователя

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Remote Control - Commands
R&S
®
NRP2
297 User Manual 1173.9157.02 ─ 03
NTRansition register The Negative TRansition register also acts as a transition filter. Upon transition
of a bit of the CONDition register from 1 to 0, the associated NTR bit determines
whether the EVENt bit is set to 1.
NTR bit = 1: the EVENt bit is set.
NTR bit = 0: the EVENt bit is not set.
This register can be written to and read. Reading the register does not change
its contents.
With the aid of these two transition filter registers the user can define the status
change of the CONDition register (none, 0 to 1, 1 to 0 or both) that is to be
recorded in the EVENt register.
EVENt register The EVENt register reports whether an event has occurred since its last read-
ing; it is the "memory" of the CONDition register. It only registers events that
have been reported by the transition filters. The EVENt register is continuously
updated by the device.
It can only be read by the user. Reading this register clears its contents.
This register is frequently referred to as the overall register.
ENABle register The ENABle register determines whether the associated EVENt bit influences
the summary bit (see below). Each bit of the EVENt register is ANDed (symbol
'&') with the associated ENABle bit. The events of all logical operations of this
register are ORed (symbol '+') and passed on to the summary bit.
ENABle bit = 0: the associated EVENt bit does not affect the summary bit. bit
= 1: if the associated EVENT bit is "1", the summary bit is also set to "1".
This register can be written to and read as required. Reading the register does
not change its contents.
Summary bit As stated above, the summary bit for each register is derived from the EVENt
and ENABle registers. The result is entered into a bit of the CONDition register
of the next higher register. The device automatically generates the summary
bit for each register. An event may thus cause a service request through all
hierarchical levels.
The Service Request Enable register (SRE) defined by IEEE488.2 can be viewed as the
ENABle register of the STB. Accordingly, the ESE can be viewed as the ENABle register
of the ESR.
STATus