Specifications

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Glossary
8B/10B encoding A block coding
scheme that maps 8-bit data values to
10-bit data values which have 3-8
transitions between 1's and 0's and a
balanced number of 1's and 0's. A
running disparity is calculated to
keep track of the balance. One 10-bit
value is used when there is positive
disparity, and a different 10-bit
value if there is neutral or negative
disparity. The 8B/10B block code
was designed by IBM in the mid-
1980's and is used in FibreChannel,
InfiniBand, and Gigabit Ethernet.
absolute Denotes the time period
or count of states between a captured
state and the trigger state. An
absolute count of -10 indicates the
state was captured ten states before
the trigger state was captured.
acquisition Denotes one complete
cycle of data gathering by a
measurement module. For example,
if you are using an analyzer with
128K memory depth, one complete
acquisition will capture and store
128K states in acquisition memory.
analysis probe A probe connected
to a microprocessor or standard bus
in the device under test. An analysis
probe provides an interface between
the signals of the microprocessor or
standard bus and the inputs of the
logic analyzer. Also called a
preprocessor.
analyzer 1 In a logic analyzer with
two machines, refers to the machine
that is on by default. The default
name is Analyzer<N>, where N is
the slot letter.
analyzer 2 In a logic analyzer with
two machines, refers to the machine
that is off by default. The default
name is Analyzer<N2>, where N is
the slot letter.
arming An instrument tool must be
armed before it can search for its
trigger condition. Typically,
instruments are armed immediately
when Run or Group Run is selected.
You can set up one instrument to arm
another using the Intermodule
Window. In these setups, the second
instrument cannot search for its
trigger condition until it receives the
arming signal from the first
instrument. In some analyzer
instruments, you can set up one
analyzer machine to arm the other
analyzer machine in the Trigger
Window.
asterisk (*) See edge terms,
glitch, and labels.
bits Bits represent the physical logic
analyzer channels. A bit is a channel
that has or can be assigned to a label.