Chapter 3. The mechanism and principle
of operation of E-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 E-502, the frequency of discrete signals (e.g., synchronization signals)
is expressed in Hertz, and not in periods per second, as it is common for frequency for a non-
sinusoidal process.
3.2. Introduction (general information)
All modifications of E-502 (
) are made on the basis of the same multilayer
PCB. Modification is achieved by different variants of the factory assembly. Changing E-502
modifications after factory assembly is not provided for.
The presence of the
ADSP-BF523 signal processor with SDRAM (modification
E-502-P-
░
-
░) is
considered justified for those users who want to get the maximum of on-board signal processing
capabilities on-board, as well as for advanced users to have their own low-level programming of the
processor, possibly with the use of the JTAG-emulator (s.
).
All E-502 modifications have a galvanic isolation of the signal circuits (for L-502 a galvanic
isolation is an option).
DAC with 2 channels (modification E-502-
░
-
░
-D) allows to display output analog voltage
levels or voltage time functions.
ADC 16 bits with a conversion frequency of up to 2 MHz with 16/32-channel circuit
switching (up to 16 differential channels, up to 32 with a common ground) with voltage subbands
of ±10 V, ±5 V, ±2 V, ±1 V, ±0.5 V, ±0.2 V has an analog ADC path, identical to L-502,
with a maximum conversion frequency of 2 MHz.
Note the limitations up to± 1 V of the operating range of the input signal on the Y and GND32
).
Instrumental DAC 16 bits 2 channels ±5 V provides the opportunity of synchronous (streaming
up to 1 MHz for a channel), asynchronous mode on the selected DAC channel, including mixed
synchronous asynchronous mode on different channels, as well as a cyclic synchronous self-oscillator
from the E-502 internal buffer (2 pages of 1.5 Mcounts.)
Digital output, 16 lines. Similarly to a DAC, it is possible to have a synchronous output of up
to 1 MHz, as well as an asynchronous output, as well as a synchronous output from an internal buffer.
With synchronous output, the frequency is matched to the frequency of the DAC output. The output
enable allocated for the low and high byte increases the flexibility of using digital lines, for example,
