Crestron e-control Database Manager, Руководство пользователя

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Crestron e-control Database Manager SW-DBM
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Appendices Installation & Reference Guide — DOC. 5823
Base 16 used for notational purposes
Straight base 2 notation (a long string of 0s and 1s) is considered to be too unwieldy
to be useful to the human eye as it is too easily prone to misrepresentation and
misinterpretation. Hexadecimal (base 16) notation is used to conveniently specify the
bit patterns for the signals that use them (
i.e., the Config and SignalA
n
signals).
Hexadecimal groups all sixteen bits into four sets of four bits each, assigning the
base 10 digits 0 to 9 plus the first six letters of the alphabet A to F to the sixteen
possible combinations of the four bits.
For example, the sixteen-bit (base 2) pattern
0 0 0 0 0 0 0 1 1 1 0 1 0 1 0 1
can be broken into the four four-bit sets
0000 0001 1101 0101
which get assigned to them the four hexadecimal “hex digits”
0 1 D 5
Note that D stands for the quantity we normally express in base 10 as thirteen (13).
Therefore, the above bit pattern is referred to conveniently as $01D5 , or since
leading zeros are optional in any base, $1D5 . The missing (high-order) bits are
assumed to be 0000. Although $1D5 represents a quantity — which happens to be
four hundred sixty-nine (469) in base 10 — again, we are only interested in bit
patterns here, not the quantities they may represent.
Error Reporting
At this time error handling is a little haphazard, with some errors being tallied back
to the control system, while others are logged in the
Server Monitor window .
Tallied Errors
A descriptive string is sent with all errors (via ErrString ). However, while some are
accompanied with error numbers (via ErrNumber + ErrTrigger ), some are not.
Log Items
The log is intended for after-the-fact analysis of important events. The log is an in-
memory FIFO list (first in, first out). When the log approaches capacity, log items
are removed, one by one, starting with the oldest items first, until there is enough
room for the new item.
All logged items are preceded with either a per-cent sign (%) or a dollar sign ($).
Items preceded with % are informational. Items preceded with $ are errors, reflecting
unanticipated situations.
Signal Summary
The “Signal Reference,” below, is an alphabetical list of all signals from both
COM Settings and Scroller signal blocks.
Certain signal names are used in both types of signal blocks. However, only one
entry for each signal type appears in the reference. Among these are the
Done signal
and the three error signals ( ErrNumber , ErrString , and ErrTrigger ). This identical
naming reflects the fact that these signals function similarly regardless of where they
appear.