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3.1: Conventions
Chapter 3. The device and principle of
operation L-502.
3.1. Conventions
3.1.1. Convention on numbering
In all products of the L-Card, the numbering of all physical objects (for example, channel
numbers) in the description of the principle of action and design is always made from one!
This agreement is completely unrelated to the encoding method in programming, where the
numbers of these physical objects can be encoded from scratch or otherwise, in the context of the
corresponding library function or programming language.
3.1.2. The assumption on the concept of "frequency"
In the documentation for L-502, the frequency of discrete signals (for examples,
synchronization signals) is expressed in Hertz, rather than in periods per second, as is customary in
the classical sense of frequency for a non-sinusoidal process.
3.1.3. The agreement on the terms "card", "board" and "module"
Literary PCI or PCI-E is translated as a card (in this case, even a L-card
). But many call it a
board. Following the terms, in this manual we will adhere to the more strict name of this
constructive unit, adopted in the ESKD - module. In particular, we will start from this point by
using the term "multimodule synchronization".
3.2. Introduction (L-502 concept)
For the users who have already used L-
780(М), L
-
783(М), L
-761, L-791, the new device L-
502 looks more like the development of this product line (L-7xx) at the new technical level. On the
other hand, it can not be asserted that L-502 is an analog of one of these products or that L-502 is
the mechanical sum of all the best characteristics of these products. Most likely, the L-502 project is
the result of an analysis of the user needs in the market segment of the above products and the result
of an engineering compromise at a modern technical level, where the most popular characteristics in
this product line were first taken into account for most applications in order to obtain the best price-
quality ratio.
L-502 has 6 modifications (
) which are based on the same multilayer printed
board. Modification is achieved by different variants of the factory assembly. If you previously
purchased an L-502 without a DAC, then the L-Card accepts orders for the installation of a DAC.
The remaining options for subsequent changes of the L-502 modifications are not considered
technically feasible.
