Rigol DS1054 is a champion - Page 1
Forum section: electronics / testgear

author: ebclr
author_rank: Super Contributor
timestamp: June 06, 2017, 11:21:19 pm
content: I'm playing with ESP32 SPI mode with this program#define CSPIN 5#include <SPI.h>unsigned char Icount = 0 ;void setup() {pinMode( CSPIN, OUTPUT);SPI.begin(18, 19, 23, 5); // sck, miso, mosi, ss (ss can be any GPIO)SPI.setFrequency( 10000000 );}void loop() {delay(10);digitalWrite( CSPIN, HIGH);SPI.transfer(Icount);digitalWrite( CSPIN, LOW);Icount++;}This program was set to SPI Clock for 30Mhzm 10Mhz, 5Mhz and 1 MhzThen I put my Rigol DS1054Z to check the signal expecting to see a crap unuseful picture, But for my surprise, the pictures are very nice and readable, I would love to see other scopes on the same price range showing the same waveform</Br></Br></Br></Br>This Rigols instrument is a beast,

author: technogeeky
author_rank: Frequent Contributor
timestamp: June 07, 2017, 12:12:07 am
content: I agree with you, though I don't know why you expected a "crap unuseful picture". The 3db bandwidth of the scope is well known to be in the 130MHz+ range, so a 30 MHz signal should be no problemo!Cheers!

author: Dwaine
author_rank: Frequent Contributor
timestamp: June 07, 2017, 12:54:26 am
content: I have a spare Raspberry PI and was looking for a Python script that simulates a demo board for test signals on a scope. I looked and did not find any. I was actually surprised that there were none.I could write a nice little Python program to simulate a Rigol test board,. I was just being lazy and thought I would grab one off the internet. Was not so easy.I also enjoy my Rigol scope.

author: CustomEngineerer
author_rank: Frequent Contributor
timestamp: June 07, 2017, 05:01:51 am
content: http://www.tek.com/lab-course/learning-oscilloscope-operation-using-raspberry-piNot what you mean?

author: JPortici
author_rank: Super Contributor
timestamp: June 07, 2017, 06:09:38 am
content: i don't get it, what did you expect? If anything you showed that you can probe correctly

author: ebclr
author_rank: Super Contributor
timestamp: June 07, 2017, 08:00:23 am
content: Pulses are well known for the huge amount of harmonics they generate, and a 10 Mhz pulse train on a 50 Mhz scope, show with that nice shape ( ok is a little slow rise time ) but is totally valid for a test or even decode by eyes.If I put this same signal on my 100Mhz Owon SDS2702 will be much worse than that I can't even trigger the signal.Basically, I'm happy with my 399 USD scope, I don't need to expand 1500 USD or more, do work with microprocessor interfaces even pushing SPI to 10 Mhz.But I still desire a Tek MSO/DPO4000B but have no extra cash to expand, for my purpose is a luxury but maybe sometime I will do an emotional orderWill be a nice thing to see the same signal on other scopes, even the big boy's ones,

author: JPortici
author_rank: Super Contributor
timestamp: June 07, 2017, 08:32:18 am
content: Quotepics? i find that hard to believe

author: Fungus
author_rank: Super Contributor
timestamp: June 07, 2017, 08:40:01 am
content: Yep, the (hacked) DS1054Z is an awful lot of 'scope for $400.

author: tautech
author_rank: Super Contributor
timestamp: June 07, 2017, 08:41:14 am
content: Quote from: JPortici on June 07, 2017, 08:32:18 amA bit of Holdoff and a falling edge trigger and it will trigger better than in the screenshots in the OP.

author: rstofer
author_rank: Super Contributor
timestamp: June 07, 2017, 05:50:16 pm
content: Quote from: tautech on June 07, 2017, 08:41:14 amEven just Single Shot would have helped. A little decoding would have been nice.

author: Dwaine
author_rank: Frequent Contributor
timestamp: June 07, 2017, 05:51:58 pm
content: Thanks. Reading it now.

author: nctnico
author_rank: Super Contributor
timestamp: June 07, 2017, 05:53:40 pm
content: Quote from: ebclr on June 07, 2017, 08:00:23 amSounds more like operator error than a problem in the oscilloscope

author: ebclr
author_rank: Super Contributor
timestamp: June 08, 2017, 04:14:17 am
content: "Even just Single Shot would have helped"The SPI contour is running, and you can watch dynamically the bit's changing on screen, this will never happen on single shot

author: newbrain
author_rank: Super Contributor
timestamp: June 08, 2017, 05:25:14 am
content: QuoteThe last screenshot looks like it's still at 10MHz, I'm curious about the actual behaviour at 30MHz.I might try when I'm back home.

author: ebclr
author_rank: Super Contributor
timestamp: June 08, 2017, 06:37:32 am
content: Here the image you asked forSoftware runs on this hardware with USB power

author: Rerouter
author_rank: Super Contributor
timestamp: June 08, 2017, 07:24:06 am
content: As your voltage is going below ground, your suffering from lead inductance, try the spring ground tip for that last one, i expect some resonably sharp edgesPersonally i am a little biased in wanting to see how well it can go as a current project of mine will likely need to probe 48MHz spi, possibly up to 84MHz and things in that frequency ballpark. (Dont yet have a dso)

author: ebclr
author_rank: Super Contributor
timestamp: June 08, 2017, 07:50:56 am
content: Still on regular probe but with a more decent ground path. I lost my spring ground somewhere

author: TK
author_rank: Super Contributor
timestamp: June 09, 2017, 06:49:30 pm
content: Waiting for my ESP32 Thing card to test on my EDUX1002G (modded to DSOX), micsig TO1104 and Agilent 54622D

author: TK
author_rank: Super Contributor
timestamp: June 16, 2017, 10:25:44 pm
content: MICSIG TO1104 100MHz 1GSa/s 4-channel Tablet scope. I added one extra test with SPI @ 40MHz

author: TK
author_rank: Super Contributor
timestamp: June 16, 2017, 10:29:51 pm
content: Keysight EDUX1002G modded to DSOX1102G. 2GSa/s 100MHz 2+1 channel. Using extra digital channel to trigger on SCK (SPI clock).

author: Fungus
author_rank: Super Contributor
timestamp: June 16, 2017, 10:47:02 pm
content: Quote from: TK on June 16, 2017, 10:29:51 pmIt would it nice to see the clock on an analog channel as well?What's on channel 1? Is that just crosstalk?

author: Rerouter
author_rank: Super Contributor
timestamp: June 16, 2017, 10:47:57 pm
content: I'm guessing all the ringing is just from the probing method used? I'd be a little concerned seeing 0.5V of noise on a 3.3V signal.Still glad to see that even with a high sampling rate, analog bandwidth will still bite me in the backside.

author: Fungus
author_rank: Super Contributor
timestamp: June 16, 2017, 10:52:58 pm
content: Quote from: Rerouter on June 16, 2017, 10:47:57 pmYep. Don't try to infer anything from the ringing when you're using ordinary probes.

author: TK
author_rank: Super Contributor
timestamp: June 16, 2017, 10:55:06 pm
content: Quote from: Fungus on June 16, 2017, 10:47:02 pmChannel 1 is MISO (there is no Slave device connected to the ESP32 board who is acting as SPI Master)

author: Fungus
author_rank: Super Contributor
timestamp: June 16, 2017, 11:02:37 pm
content: Quote from: TK on June 16, 2017, 10:55:06 pmOk, so it's probably just crosstalk/coupling inside the ESP32.

author: TK
author_rank: Super Contributor
timestamp: June 17, 2017, 12:14:57 am
content: Quote from: Rerouter on June 16, 2017, 10:47:57 pmYou are correct, I am using breadboard and standard ground loop

author: TK
author_rank: Super Contributor
timestamp: June 17, 2017, 12:16:28 am
content: Keysight EDUX1002G modded to DSOX1102G. 2GSa/s 100MHz 2+1 channel.

author: ebclr
author_rank: Super Contributor
timestamp: June 18, 2017, 09:09:33 am
content: It's interesting that in the Rigol, you can see the counting transactions ( Channel 2 blue ) and in Keysight you see a freeze counting value Showing that only 1 waveform is acquired while on Rigol was many, I guess was 32 since you can see a transition on 5 bitI guess you use a too long GND path, try remake with all probes GND connect to the GND pin near the 0 button or right near PIN 21, there is a better and short GND who probably will make a more nice waveform, with less inductive effect on probe

author: plazma
author_rank: Frequent Contributor
timestamp: June 18, 2017, 09:19:28 am
content: Are you using the original edux model probes? Weren't they only 70Mhz?

author: ebclr
author_rank: Super Contributor
timestamp: June 18, 2017, 09:41:17 am
content: Tk do you have access to a Siglent 100Mhz arb generator?Would be interesting to make a comparative in another scenario based on signals from that generator

author: TK
author_rank: Super Contributor
timestamp: June 18, 2017, 01:20:55 pm
content: Quote from: plazma on June 18, 2017, 09:19:28 amI am using the 200MHz probes from the micsig. I will retest on the Keysight with the stock 70MHz probes.

author: TK
author_rank: Super Contributor
timestamp: June 18, 2017, 01:24:53 pm
content: Quote from: ebclr on June 18, 2017, 09:41:17 amI don't have a Siglent arb generator. I have a Rohde & Schwarz CMU200 with RF signal generator (up to 2.7GHz) and the EDUX1002G with 20MHz wavegen. I can do AM/FM modulation on both of them.

author: Fungus
author_rank: Super Contributor
timestamp: June 18, 2017, 01:43:06 pm
content: Quote from: TK on June 18, 2017, 01:20:55 pmKeysight ships 70MHz probes? Seriously? How do they even manage to make them that bad?There's a thread on here somewhere testing the cheapest cheap-ass Chinese probes ever and they were fine up to 300MHz.https://www.eevblog.com/forum/reviews/cheapest-100mhz-oscilloscope-probes-hands-on-review/msg99256/#msg99256Edit: I think we have the answer:https://www.eevblog.com/forum/testgear/new-keysight-scope-1st-march-2017/msg1220323/#msg1220323

author: TK
author_rank: Super Contributor
timestamp: June 18, 2017, 03:06:53 pm
content: Quote from: Fungus on June 18, 2017, 01:43:06 pmThe link shows the Keysight 200MHz probe that is shipped with the DSOX1000 models. The EDUX1000 models ship with 70MHz probes because it is a 50Mhz scope.

author: Fungus
author_rank: Super Contributor
timestamp: June 18, 2017, 03:53:03 pm
content: Quote from: TK on June 18, 2017, 03:06:53 pmAll true, but irrelevant.I'm just wondering how anybody manages to make a probe that only goes to 70MHz these days.ie. Is it really possible to save enough money to make up for the extra costs of manufacturing/stocking multiple probes?

author: Fungus
author_rank: Super Contributor
timestamp: June 18, 2017, 04:03:57 pm
content: Quote from: Fungus on June 18, 2017, 03:53:03 pmCynical Fungus might suspect they actuallylosemoney by making really bad 70Mhz probes but make up for it by doubling or tripling the price of their 'premium' 300MHz probes.