Signal Lists
13 Signal Lists
13.1
Conventions
The terms assertion and de-assertion are used extensively when describing signals, to
avoid confusion when working with a mix of active-high and active-low signals. The
term assert, or assertion, indicates that the signal is active, independent of whether the
active level is represented by a high or low voltage. The term de-assert, or de-
assertion, indicates that the signal is inactive.
Signal names may or may not have a “#” at appended to them. The “#” symbol at the
end of a signal name indicates that the active, or asserted state occurs when the signal
is at a low voltage level. When “#” is not present after the signal name the signal is
asserted when at the high voltage level.
Differential pairs use the “#” to indicate the “negative” signal in the pair. The “positive”
signal in When discussing data values used inside the component, the logical value is
used; that is, a data value described as “1101b” would appear as “1101b” on an active-
high bus, and as “0010b” on an active-low bus. When discussing the assertion of a
value on the actual signal, the physical value is used; that is, asserting an active-low
signal produces a “0” value on the signal.
Typical frequencies of operation for the fastest operating modes are indicated. Test
guardbands are not included. No frequency is mentioned for asynchronous or analog
signals.
Some signals or groups of signals have multiple versions. These signal groups may
represent distinct but similar ports or interfaces, or may represent identical copies of
the signal used to reduce loading effects. Table 13-1 shows the conventions used in this
document.
Curly-bracketed non-trailing numerical indices, for example, “{X/Y}”, represent
replications of major buses. Square-bracketed numerical indices, , “[n:m]” represent
functionally similar but logically distinct bus signals; each signal provides an
independent control, and may or may not be asserted at the same time as the other
signals in the grouping. In contrast, trailing curly-bracketed numerical indices, for
example, “{x/y}” typically represent identical duplicates of a signal; such duplicates
are provided for electrical reasons.
Table 13-1. Signal Naming Conventions
Convention
Expands to
RR{0/1/2}XX
RR[2:0]
Expands to: RR0XX, RR1XX, and RR2XX. This denotes
similar signals on replicated buses.
Expands to: RR[2], RR[1], and RR[0]. This denotes a
bus.
RR{0/1/2}
Expands to: RR2, RR1, and RR0. This denotes electrical
duplicates.
RR# or RR[2:0]# Denotes an active low signal or bus.
Table 13-2 lists the reference terminology used for signal types.
Intel® 6400/6402 Advanced Memory Buffer Datasheet
155
INTEL [ INTEL ]
