SDS1104X-E Review Decode Section - Page 1
Forum section: electronics / beginners

author: BigLazz
author_rank: Contributor
timestamp: April 02, 2023, 02:18:10 pm
content: G'day,I have been reading the excellent EEVBlog long review of the Siglent scope sds1104x-e but can't find the section relating to decoding. It is referred to in other parts of the review so I assume it's around somewhere. Does anybody know where it is? Can anybody confirm it was actually written?Many Thanks.

author: tautech
author_rank: Super Contributor
timestamp: April 03, 2023, 09:50:09 am
content: Quote from: BigLazz on April 02, 2023, 02:18:10 pmWelcome to the forum.Can't you find what you need here:https://www.eevblog.com/forum/testgear/siglent-sds1204x-e-released-for-domestic-markets-in-china/In the very first post is an example of dual duplex decoding using all 4 channels or is there something else you particularly need to see ?

author: BigLazz
author_rank: Contributor
timestamp: April 03, 2023, 01:38:05 pm
content: Thanks mate. I'll try using that.I'm just trying to decode I2c but it keeps telling me there is no data. I've got the two channels connected and I'm getting a decent wave output but the decode just keeps saying no data.

author: tautech
author_rank: Super Contributor
timestamp: April 03, 2023, 09:53:17 pm
content: Quote from: BigLazz on April 03, 2023, 01:38:05 pmJust try to do basic for now and assign channels and set thresholds correctly.You will need to set a trigger holdoff to longer than a byte or packet.Take some screenshots to USB using the Print button and add them to a post using the Attachments feature.Have relevant menus showing so we can see how you have set the scope and offer guidance.I have a I2C board here so can post examples if required.

author: rstofer
author_rank: Super Contributor
timestamp: April 03, 2023, 11:07:01 pm
content: The procedure starts on page 79 here:https://siglentna.com/USA_website_2014/Documents/UserManual/SDS1000X&Xplus_UserManual_UM0101X-E02A.pdfHave you done step 5b correctly? It seems like you have a disagreement on which channel is carrying data.I have the Rigol DS1054 scope so I know exactly nothing about the Siglent.

author: BigLazz
author_rank: Contributor
timestamp: April 04, 2023, 11:40:34 am
content: Thanks mate. Will do

author: BigLazz
author_rank: Contributor
timestamp: April 04, 2023, 11:42:38 am
content: Thanks mate. I'll take a look at that guide.It's not the wrong channels. I've double checked SCL & SDA are the right way around.

author: rstofer
author_rank: Super Contributor
timestamp: April 04, 2023, 01:26:51 pm
content: You can connect SDA to channel 2 (and SCK to channel 1) and display channel 2 as the data signal on the screen and everything will look correct but if channel 3 is inadvertently selected for data with the menu, there won't be any data to decode.

author: rstofer
author_rank: Super Contributor
timestamp: April 04, 2023, 01:38:39 pm
content: What are you using for an I2C source? You can use a couple of Arduinos to make a test setuphttps://docs.arduino.cc/learn/communication/wireI have always had some difficulties with I2C and avoid using it at every opportunity. Once I finally get it set up correctly it works fine but there have been times when I wanted to chuck the whole project. I go out of my way to find peripherals with an SPI interface.The Raspberry Pi is another useful tool:https://learn.adafruit.com/adafruits-raspberry-pi-lesson-4-gpio-setup/configuring-i2c

author: BigLazz
author_rank: Contributor
timestamp: April 05, 2023, 12:34:11 pm
content: Does that mean I must only use ch1 for clock and ch2 for data?I didn't think it mattered as long as I selected the correct channels in the configure.

author: rstofer
author_rank: Super Contributor
timestamp: April 05, 2023, 03:28:41 pm
content: Quote from: BigLazz on April 05, 2023, 12:34:11 pmI don't think it matters which of the 4 channels you assign to the two signals. I don't recall seeing any such admonition in the User Manual but they use Channel 1 for SCL and Channel 2 for SDA. On page 79 they also talk about setting the threshold voltage (typically 1.6V). I don't know that this is appropriate for both 3.3V and 5.0V devices. What is your Vcc?As you get the channels set up, take USB screen shots and post them here. I would expect your screenshots to look the same as those in the User Manual except maybe for Vcc issues: Threshold setting and V/div setting.Page 80 talks about setting up the trigger to start the capture with the I2C Start Condition (plus a bunch of others). The scope is very capable of dealing with the I2C protocol.

author: tautech
author_rank: Super Contributor
timestamp: April 06, 2023, 09:25:55 am
content: BL, some screenshots to follow.There's some interesting stuff here in that one must think about some settings or zero results will be obtained.Particularly edges and little things like a CS setting for the normal Idle Low protocol need be instead a ~CS setting.It also seemed a Rising trigger was needed which is very confusing when an active Low signal is being used.(taking that to Siglent for an explanation)Hopefully screenshots will tell the rest of the story but do ask questions as required.Source = SDS1104X-E and stock probes with STB-3

author: BigLazz
author_rank: Contributor
timestamp: April 06, 2023, 12:46:18 pm
content: Thanks mate. I'll do that. And a million thankyous for helping me.

author: BigLazz
author_rank: Contributor
timestamp: April 06, 2023, 12:49:37 pm
content: Awesome! Will use these. Thanks for helping.

author: BigLazz
author_rank: Contributor
timestamp: April 15, 2023, 06:41:43 am
content: Thanks for all the great help you blokes are giving. I've taken a screenshot of what is happening....I have an I2C transmission between two arduinos. It is using the Wire examples for MasterWrite and SlaveReceive. The string being sent is "x is n" and is increased by a value of one each time.There must just be seomthing I am missing.

author: BigLazz
author_rank: Contributor
timestamp: April 15, 2023, 06:45:29 am
content: Thanks mate. I'ver got the waves looking like that but I can't get the decode output. I've attached a screenshot later in this thread.

author: BigLazz
author_rank: Contributor
timestamp: April 15, 2023, 07:16:13 am
content: Woot!!! Now I'm getting something!Somebody suggested earlier that I had my channels the wrong way around. That day I didn't but today I did. Put them the right way round and it works!!!!Thanks so much for all the help youse have given me. I am stoked this is workingA blog where people who know what they are doing actually stop to help a noob is just awesome!I even bought an EEVBLOG multimeter as a sign of appreciation.Thanks again.

author: tautech
author_rank: Super Contributor
timestamp: April 15, 2023, 07:28:46 am
content: Quote from: BigLazz on April 15, 2023, 06:45:29 amGood, well done !FYI, use the Quote button to reply to a post and only the Reply when you just need to post something not relevant to a previous reply.Another FYI, taake a second or 2 more before pressing Print so the USB detected message disappears.

author: pdenisowski
author_rank: Super Contributor
timestamp: April 15, 2023, 09:26:46 am
content: Glad you got it working!Enough people run into issues trying to set up serial decodes on oscilloscopes that I just (like, in the last couple of days) completed a series of videos on how to do this on our new MXO series oscilloscopes. I also did pure technology videos on UART, SPI, and I2C - the I2C one will be on YouTube next week: SPI and UART are already live.Usually the issue with decoding I2C (and many serial protocols) is incorrect vertical and horizontal settings or thresholds. There's very little else to configureThat said, I have also beat my head against the wall trying to decode something when I had the channels incorrectly assigned ....

author: pdenisowski
author_rank: Super Contributor
timestamp: April 15, 2023, 09:29:40 am
content: Quote from: rstofer on April 04, 2023, 01:38:39 pmThis. I actually used a Raspberry Pi when developing my recent videos on low speed serial decodes. Arduino is also very good (and cheaper / more available than the Pi right now ...) for generating test traffic, especially for automotive protocols like CAN and LIN.

author: BigLazz
author_rank: Contributor
timestamp: April 16, 2023, 01:50:41 pm
content: Quote from: pdenisowski on April 15, 2023, 09:26:46 amWhen I start using UART and Spi these videos will be my first port of call. Thanks mate.

author: pdenisowski
author_rank: Super Contributor
timestamp: April 18, 2023, 02:03:43 pm
content: The "Understanding I2C" video I mentioned is now live on the Rohde & Schwarz YouTube channel

author: BigLazz
author_rank: Contributor
timestamp: April 19, 2023, 09:28:47 am
content: Quote from: pdenisowski on April 18, 2023, 02:03:43 pmAwesome. A million thankyous 😁

author: BigLazz
author_rank: Contributor
timestamp: April 30, 2023, 11:44:27 am
content: Thanks again for all the help. I'm loving this machine. A mate had put together a high frequency speaker generator to scare off rats. I plugged it in and figured out how to find the frequency we can't hear (over 50KHZ)! All it took was a turn of the horizontal scale to get all the pulses...Later: I just googled it and rats can hear up to 80KHZ. But 50KHZ actually attracts them! Oh dear. Back to the drawing board.

author: BigLazz
author_rank: Contributor
timestamp: May 01, 2023, 06:08:36 am
content: Quote from: pdenisowski on April 18, 2023, 02:03:43 pmMate, this video is triffick! So clear and easy to understand. I've subsrcibed to your channel.

author: pdenisowski
author_rank: Super Contributor
timestamp: May 01, 2023, 08:14:10 am
content: Quote from: BigLazz on May 01, 2023, 06:08:36 amThanks! In addition to I2C, I've also done videos on UART and SPI, and I have a couple more serial protocol decode videos under development right now (probably out sometime in the summer).