|
|
== https://es.technikum-wien.at/openlab/openlab_wiki/wikis/home[Home] | https://es.technikum-wien.at/openlab/openlab_wiki/wikis/SOTA_osci_uC[<Micro-controller-based projects/products] | https://es.technikum-wien.at/openlab/openlab_wiki/wikis/SOTA_osci_SC[Soundcard-based projects/products>]
|
|
|
|
|
|
= FPGA/CPLD-based projects/products
|
|
|
|
|
|
This chapter gives an overview of the FPGA/CPLD-based solutions found during the research process.
|
|
|
In particular, the differences of the products in terms of performance, features, price and the applied fundamental technology should be further discussed.
|
|
|
|
|
|
{empty} +
|
|
|
|
|
|
== FPGA-Oscilloscope California Institute of Technology
|
|
|
|
|
|
The FPGA-Oscilloscope [1] was developed by students of the California Institute of Technology during a class project. It features two analog input channels and an 8-bit digital analyzer.
|
|
|
The results are displayed on a built-in LC-display which is shown in figure 1.
|
|
|
|
|
|
{empty} +
|
|
|
|
|
|
image::https://es.technikum-wien.at/openlab/openlab_wiki/wikis/img/SOTA_osci/SOTA_osci_FPGA_osci.png[caption="Figure 1: ",title="FPGA-Oscilloscope by students of the California Institute of Technology (1)",height=300,align="center"]
|
|
|
|
|
|
{empty} +
|
|
|
|
|
|
The device is a stand-alone product which does not need any access to additional hardware in order to be fully operational.
|
|
|
All functions of the oscilloscope are controlled by hardware buttons and knobs.
|
|
|
This results in a familiar look and feel like the controls of a traditional digital oscilloscope. The whole project is open-source and well documented.
|
|
|
|
|
|
{empty} +
|
|
|
|
|
|
=== Hardware
|
|
|
|
|
|
The FPGA Oscilloscope uses a Altera Cyclone III FPGA which runs a NIOS II [2] softcore. The structure of the FPGA design and the relations to peripheral hardware is shown in figure 2.
|
|
|
|
|
|
{empty} +
|
|
|
|
|
|
image::https://es.technikum-wien.at/openlab/openlab_wiki/wikis/img/SOTA_osci/SOTA_osci_FPGA_osci_block.png[caption="Figure 2: ",title="Block diagram of the FPGA-Oscilloscope (1)",height=400,align="center"]
|
|
|
|
|
|
{empty} +
|
|
|
|
|
|
A AD9288 ADC, capable of capturing at 100MSa/s, is directly connected to the FPGA.
|
|
|
Besides the softcore the FPGA also contains logic for the LC-display, buttons and rotary switches as well as a trigger logic.
|
|
|
The FPGA is also interfacing with a flash component, as well as SRAM and VRAM for the display.
|
|
|
|
|
|
{empty} +
|
|
|
|
|
|
=== Specification
|
|
|
|
|
|
As mentioned by the manual of the FPGA-Oscilloscope [3], the device is able to measure analog signals up to a maximum frequency of about 5MHz.
|
|
|
In terms of voltage it can handle -12V to +12V signals. The digital inputs features the same bandwidth specifications and are designed to capture 5V- and 3.3V-logic signals.
|
|
|
|
|
|
{empty} +
|
|
|
|
|
|
Table 1 summarizes the specifications and the pricing of this project.
|
|
|
|
|
|
{empty} +
|
|
|
|
|
|
image::https://es.technikum-wien.at/openlab/openlab_wiki/wikis/img/SOTA_osci/SOTA_osci_FPGA_osci_table1.PNG[caption="Table 1: ",title="Specifications of the FPGA-Oscilloscope",align="center"]
|
|
|
|
|
|
{empty} +
|
|
|
|
|
|
The price of the whole project is derived from the Bill-of-Materials of the FPGA-Oscilloscope project. +
|
|
|
It is an approximate estimation because of missing information regarding the used components and pricing.
|
|
|
|
|
|
{empty} +
|
|
|
|
|
|
== OsciPrime
|
|
|
|
|
|
The OsciPrime [4] was developed at the University of Applied Sciences Northwestern Switzerland in 2010 as part of multiple bachelor theses.
|
|
|
In contrast to the typical way of displaying the measured results, this device connects to hardware running Android-OS.
|
|
|
Figure 3 shows the PCB of the OsciPrime with some of its components named.
|
|
|
|
|
|
{empty} +
|
|
|
|
|
|
image::https://es.technikum-wien.at/openlab/openlab_wiki/wikis/img/SOTA_osci/SOTA_osci_Osciprime_board.png[caption="Figure 3: ",title="Picture of the OsciPrime hardware (4)",height=350,align="center"]
|
|
|
|
|
|
{empty} +
|
|
|
|
|
|
The Android application as well as the design of the CPLD are open-source. Schematics and layouts are available for free.
|
|
|
The whole project is very well documented and a pre-built device can be purchased for approx. 261 euro.
|
|
|
|
|
|
{empty} +
|
|
|
|
|
|
=== Hardware
|
|
|
|
|
|
The heart of the OsciPrime are the 6 MSa/s capable ADC08100 ADCs.
|
|
|
Those 8 bit ADCs are directly connected to a Xilinx Coolrunner II CPLD, which arranges the sampled data for a USB-controller.
|
|
|
The USB-controller, a Cypress FX2, then outputs the data to a android running device.
|
|
|
The CPLD acts as master towards the FX2 and pushes the sampled signal into its FIFO memory. This stabilizes data transmission.
|
|
|
|
|
|
{empty} +
|
|
|
|
|
|
=== Android application
|
|
|
|
|
|
The GUI of the Android application, shown in figure 4, has a similar structure to that of a typical digital oscilloscope.
|
|
|
To display the measured waveform, the application uses the whole screen of the device. Settings are hidden under additional menus, accessible through on-screen buttons.
|
|
|
|
|
|
{empty} +
|
|
|
|
|
|
image::https://es.technikum-wien.at/openlab/openlab_wiki/wikis/img/SOTA_osci/SOTA_osci_Osciprime_gui.png[caption="Figure 4: ",title="Screenshot of the OsciPrime Android application (5)",height=320,align="center"]
|
|
|
|
|
|
{empty} +
|
|
|
|
|
|
As additional feature this software is capable of visualizing audio signals as well. Those can be inputed by a built-in microphone or by attaching a external source via a jack plug.
|
|
|
|
|
|
{empty} +
|
|
|
|
|
|
=== Specification
|
|
|
|
|
|
Table 2 summarizes the specifications and the pricing of the OsciPrime oscilloscope.
|
|
|
|
|
|
{empty} +
|
|
|
|
|
|
image::https://es.technikum-wien.at/openlab/openlab_wiki/wikis/img/SOTA_osci/SOTA_osci_Osciprime_table2.PNG[caption="Table 2: ",title="Specifications of the OsciPrime oscilloscope",align="center"]
|
|
|
|
|
|
{empty} +
|
|
|
|
|
|
Featuring two analog channels, each connected to a ADC08100 ADC, the OsciPrime is able to measure signals up to a frequency of 8 MHz.
|
|
|
The ADCs are sampling at 6 MSa/s with a 8 bit resolution. The voltage of the signal can range between -16 to +16V.
|
|
|
This project is commercial available and can be purchased at the companies website [4].
|
|
|
|
|
|
{empty} +
|
|
|
|
|
|
== PicoScope 2200 Series
|
|
|
|
|
|
Pico Technology, a company providing portable measurement equipment, lists a wide range of USB connected oscilloscopes ranging from 10 up to 200 MHz of input bandwidth.
|
|
|
Figure 5 shows the PicoScope and the included accessories.
|
|
|
|
|
|
{empty} +
|
|
|
|
|
|
image::https://es.technikum-wien.at/openlab/openlab_wiki/wikis/img/SOTA_osci/SOTA_osci_pico_package.jpg[caption="Figure 5: ",title="PicoScope and accessories (6)",height=320,align="center"]
|
|
|
|
|
|
{empty} +
|
|
|
|
|
|
The one with 10 MHz bandwidth retails for € 95.59 without a pair of oscilloscope probes. This commercial product is closed source and only limited information off the hardware is available.
|
|
|
|
|
|
{empty} +
|
|
|
|
|
|
=== PC-software
|
|
|
|
|
|
The interface of the PicoScope software features a customizable split-screen which enables multiple channels, or different views of the signals, to be shown at the same time.
|
|
|
Therefore, as shown in figure 6, it is possible to look at a signal over time while observing the spectrum of the signal.
|
|
|
|
|
|
{empty} +
|
|
|
|
|
|
image::https://es.technikum-wien.at/openlab/openlab_wiki/wikis/img/SOTA_osci/SOTA_osci_pico_soft.png[caption="Figure 6: ",title="User interface of the PicoScope software showing the split-screen feature (6)",height=320,align="center"]
|
|
|
|
|
|
{empty} +
|
|
|
|
|
|
As an additional feature the PicoScope software provides some math calculation, like addition, subtraction or filters, applied on the displayed input signal.
|
|
|
Also it is possible to let the program trigger an action when different events occur. For example it can play a sound if the buffer is full.
|
|
|
|
|
|
{empty} +
|
|
|
|
|
|
=== Specification
|
|
|
|
|
|
The relevant model of the PicoScope 2200 Series [6], regarding this state of the art research,
|
|
|
is the PicoScope 2204A. This two channel digital oscilloscope is able to measure signals up to
|
|
|
a frequency of 10 MHz and 40V peak to peak voltage as the maximum values. As an additional
|
|
|
feature the PicoScope also includes a signal generator, which enables analog waveform generation.
|
|
|
It is able to generate all typical waveforms (sine, square, triangle, ...) at a maximum
|
|
|
frequency of 100 kHz and 4V peak to peak voltage. The PicoScope is also able to capture
|
|
|
digital signals and decode the following protocols: CAN, LIN, I2C, UART/RS232, SPI, I2S and
|
|
|
FlexRay.
|
|
|
Table 3 lists some relevant specifications of the PicoScope oscilloscope.
|
|
|
|
|
|
{empty} +
|
|
|
|
|
|
image::https://es.technikum-wien.at/openlab/openlab_wiki/wikis/img/SOTA_osci/SOTA_osci_pico_table.PNG[caption="Table 3: ",title="Specifications of the PicoScope 2204A oscilloscope",align="center"]
|
|
|
|
|
|
{empty} +
|
|
|
|
|
|
The PicoScope 2204A is the only FPGA/CPLD-based oscilloscope, at a price range of ~100€, which features ETS.
|
|
|
Non of the open-source projects found during the research are able to perform signal acquisition using ETS.
|
|
|
|
|
|
{empty} +
|
|
|
|
|
|
== Bibliography
|
|
|
|
|
|
. CALIFORNIA INSTITUTE OF TECHNOLOGY: _GitHub webpage of the FPGA-Oscillopscope project_ [Online] https://github.com/agural/FPGA-Oscilloscope[GitHub webpage of the FPGA-Oscillopscope project]
|
|
|
. ALTERA CORPORATION: _NIOS II softcore - overview_ [Online] https://www.altera.com/products/processors/overview.html[NIOS II softcore - overview]
|
|
|
. GURAL, A.: _FPGA Oscilloscope Manual_, California Institute of Technology, July 2014
|
|
|
. NEXUS-COMPUTING SWITZERLAND: _OsciPrime - main webpage_ [Online] http://www.osciprime.com/index.php?p=project[OsciPrime - main webpage]
|
|
|
. NEXUS-COMPUTING SWITZERLAND: _OsciPrime_, Techn. Rep, Nexus-Computing Switzerland, August 2010
|
|
|
. PICO TECHNOLOGY: _PicoScope 2200 Series- product page_ [Online] https://www.picotech.com/oscilloscope/2200/picoscope-2200-features[PicoScope 2200 Series- product page]
|
|
|
|
|
|
{empty} +
|
|
|
|
|
|
== https://es.technikum-wien.at/openlab/openlab_wiki/wikis/home[Home] | https://es.technikum-wien.at/openlab/openlab_wiki/wikis/SOTA_osci_uC[<Micro-controller-based projects/products] | https://es.technikum-wien.at/openlab/openlab_wiki/wikis/SOTA_osci_SC[Soundcard-based projects/products>] |