Digilent  Analog Discovery 2 - Page 1
Forum section: electronics / testgear

author: JoeyG
author_rank: Regular Contributor
timestamp: July 14, 2016, 02:16:22 pm
content: Features look good on paper.Has anyone tried the logic analyser for SPI and I2C decoding etcChannels: 16 (shared)32)Sample rate (real time): 100 MSPSBuffer size/channel: up to 16K samples33)Input logic: LVCMOS (1.8V/3.3V, 5V tolerant)Multiple trigger options including pin change, bus pattern, etc34).Cross-triggering between Analog input channels, Logic Analyzer, Pattern Generator or external trigger35).Interpreter for SPI, I2C, UART, Parallel bus36).Data file import/export using standard formats37).36 This functionality is implemented by WaveForms software in the PC, using the buffered data from the FPGA. After a acquiring a complete data buffer at the FPGA level and uploading it to the PC, the data is processed and displayed, while a new acquisition is started.Thanks Joe

author: Howardlong
author_rank: Super Contributor
timestamp: July 14, 2016, 04:08:49 pm
content: Yes, it works, but it's limited by memory, so you don't get very long decodes.This, and its previous model which functionally is almost identical bar the variable PSU, are about as good as it gets at this end of the market in USB scopes. A lot of this is because of the software.

author: rstofer
author_rank: Super Contributor
timestamp: July 14, 2016, 04:16:31 pm
content: I haven't tried decoding on my V1 device but I have used the AWGs and Scope channels quite a bit. I like the device, I like being able to use multiple components and I especially like being able to move the scope display to one monitor and leaving the AWG display on the other. There's nothing like dual 27" instruments!Where it really shines is when you dump it in a laptop bag and take it somewhere. A complete lab in a small box.Again, I haven't tried it but I suspect I can trigger the capture to start anywhere I want if I can send a synch pulse from the DUT. I could decide to skip all the useless traffic on the port and capture only the portion of interest.

author: Howardlong
author_rank: Super Contributor
timestamp: July 14, 2016, 04:24:38 pm
content: Yes, the portability aspect is its greatest facet for me. A miniature electronics Swiss army knife.One caveat though. If you're after a scope for anything more than casual occasional use, this is not a match for a proper bench scope, and it never will be. As long as you can accept its limitations, it's very useful. I'd also strongly recommend investing in the BNC board and 10X probes.

author: pascal_sweden
author_rank: Super Contributor
timestamp: July 15, 2016, 09:06:01 am
content: I personally think that the Mark I version of the Analog Discovery looked nicer, and more professional,but of course that is a personal taste.I am keen on buying it for the Bode plot functionality, and as a basic Logic Analyzer.Some distributors still carry the Mark I, so I probably will go for that one, as I don't care about the extra power lines.Or is there another big difference between the two? Same noise level, signal fidelity?Is the difference in bandwidth really that big, as per below? This is new information for me!https://blog.digilentinc.com/whats-the-difference-student-tools/

author: Howardlong
author_rank: Super Contributor
timestamp: July 15, 2016, 09:36:22 am
content: I did a 1:1 comparison here:https://youtu.be/HXu2RxfJkKcThey perform pretty much identically. Note that since that video I am aware that Digilent have been investing time in implementing some form of interpolation in their Waveforms software, I don't know if it's been released or not yet.