Author Topic: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review  (Read 4619 times)

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Online EEVblog

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$140 for a 2CH 100MHz 1GS/s tablet oscilloscope?
Review of the $140 FNIRSI-1013D 2CH 100MHz 1GS/s tablet oscilloscope.
Is it too good to be true?
Fnirsi Aliexpress Store: http://s.click.aliexpress.com/e/_d8nfjVK



FNIRSI 1013D Portable Tablet Oscilloscope PCB by Dave Jones, on Flickr
« Last Edit: July 05, 2020, 06:45:26 am by EEVblog »
 
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Offline SeanB

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Re: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review
« Reply #1 on: July 05, 2020, 07:24:05 am »
Any idea on the 2 LED's, I would guess the red is to indicate USB charge, and the green is for fully charged battery, as there is nothing reallt visible on the PCB there other than the charge controller and battery manager.
 
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Online firewalker

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Re: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review
« Reply #2 on: July 05, 2020, 10:10:03 am »
This thing + attenuator + ignition probe could be useful as a cheap automotive oscilloscope.

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Offline fkfaraz

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Re: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review
« Reply #3 on: July 05, 2020, 11:29:08 am »

hello

sorry for my bad english and long post!!!
this o'scope has been in my list since released date. I even enquire about it in some thread here and one member promised to do a review after getting his hands on it....

for starters i am a complete noob. Although I have an electronics degree, but after degree I went to the service side of things where electrical and mechanical skill were required, so i have forgotten many electronics related skills etc, although i am picking up interest in electronics again.

now, i did not have an o'scope. and my interest is still in early stages so i do not want to burn some 6 to700 bucks for a micsig( with knobs). Yes, i know about rigol and siglent but micsig is battery powered and there is a lot of power issues at my place so.
i was thinking, is it useful for a hobbyist like me. even if it is useful for mare 10 mhz only.  :blah: :blah:
can i measure some basic ckts with it like voltage reg, op-amp, and those educational ckts which is in my electronics devices book??
 :popcorn: :popcorn:
 

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Offline iak

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Re: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review
« Reply #5 on: July 05, 2020, 01:53:37 pm »
The main soc is All Winner is F1C100s  which is an ARM  ARM926EJ-S  core running at 533MHz, the same SOC is used in LicheePi Nano and the same SOC that somebody used to make a Linux bussniess card https://www.thirtythreeforty.net/posts/2019/12/my-business-card-runs-linux/. Its very cheap, 1.5$ a pop and there is a significant info about it online.

If the SD card does not have the main OS image, it  can be easily hacked to contain it, the pirmary bootloader and maybe tiny os on the winbound eeprom. It can be easily flashed with Uboot and made to read a linux image from the SD card. 
 

Offline exile

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Re: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review
« Reply #6 on: July 05, 2020, 08:41:00 pm »
If I have not missed anything then they are missing sample memory, because what is in fpga is only 270Kb ~ 34KB and it is not enough for 240Ksample.
Sure, the ARM CPU has access to DDR1 SIP memory but not FPGA.
 

Offline pickle9000

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Re: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review
« Reply #7 on: July 05, 2020, 09:48:43 pm »
It would be so interesting to see a manufacturer open up and publish the firmware for a device like this. It would be an interesting see if it kills the production run or has the effect of pushing sales. 
 

Offline Martin72

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Re: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review
« Reply #8 on: July 05, 2020, 09:53:41 pm »
I would rather spend 140bucks for an old used one than on this piece.
So it seems that the tablet scopes from micsig are the only affordable ones who worked well.
No, must correct myself, it seems they´re the ONLY one who offers tablet scopes... ???
 
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Offline pickle9000

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Re: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review
« Reply #9 on: July 05, 2020, 10:10:25 pm »
I was thinking more along the lines of what could you use this for. Educational scopes are rare, same with automotive and so on. A purpose made interface that limits features or adds others is interesting to me.
 

Offline MadTux

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Re: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review
« Reply #10 on: July 05, 2020, 11:28:18 pm »
I would rather spend 140bucks for an old used one than on this piece.
So it seems that the tablet scopes from micsig are the only affordable ones who worked well.
No, must correct myself, it seems they´re the ONLY one who offers tablet scopes... ???
2Channels and no memory, nice toy with no use.
Would get a HP 54621A/D, HP 54622A/D or HP 54645A for that money. Old but still somewhat usable for simple things, compared to this toy. At least they have deep memory and mixed signal capability in D version.
 

Online EEVblog

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Re: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review
« Reply #11 on: July 06, 2020, 01:49:09 am »
i was thinking, is it useful for a hobbyist like me. even if it is useful for mare 10 mhz only.  :blah: :blah:
can i measure some basic ckts with it like voltage reg, op-amp, and those educational ckts which is in my electronics devices book??

Sure it's useful, just expect a few issues with it. others have reported triggering problems under various conditions, but haven't checked that myself yet.
As I said in the video, perhaps a Hantek USB scope is better value, and cheaper.
 
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Online EEVblog

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Re: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review
« Reply #12 on: July 06, 2020, 01:50:31 am »
2Channels and no memory, nice toy with no use.

240k memory is hardly "no memory". Shame you just can't scroll through it in detail.
 

Online EEVblog

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Re: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review
« Reply #13 on: July 06, 2020, 01:51:28 am »
If I have not missed anything then they are missing sample memory, because what is in fpga is only 270Kb ~ 34KB and it is not enough for 240Ksample.
Sure, the ARM CPU has access to DDR1 SIP memory but not FPGA.

I didn't even think to check that.  >:(
 

Offline NiHaoMike

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Re: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review
« Reply #14 on: July 06, 2020, 02:18:25 am »
If I have not missed anything then they are missing sample memory, because what is in fpga is only 270Kb ~ 34KB and it is not enough for 240Ksample.
Sure, the ARM CPU has access to DDR1 SIP memory but not FPGA.
What is the bandwidth between the FPGA and ARM? Perhaps a replacement firmware will allow use of the entire available RAM at lower sample rates.
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Online ace1903

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Re: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review
« Reply #15 on: July 06, 2020, 07:53:59 am »
FPGA and CPU are connected using GPIOE 12bit port so do not expect huge bandwidth.
I used ARM926 core in custom ASIC around 2007. When you load internal memory with graphic you can expect performances of low-end smartwatch.
On manual is written 240kpoint like bits not like samples.  So one can expect ~30k samples.
My opinion is that this hardware is not worth to be open-sourced and used for scope development.
Raspberry pi + (FPGA + ADC card ) extension card will be much more worth spending time on.   
 
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Offline iscle

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Re: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review
« Reply #16 on: July 06, 2020, 05:44:57 pm »
I have bought this scope mainly because I needed one and this one runs Linux (yay!), and I can customize the firmware if other people is willing to help.

As ace1903 said, the FPGA is connected to the main SOC via a 12bit port, but they are only using 11 of those bits (as far as I can tell from the high-res pictures posted by Dave), so that limits the bandwidth even more. I don't think this will be a problem when using only 1 channel, but when using both it will be a bottle-neck for sure.

Can anyone dump the SPI flash (containing the firmware) so that we can start analyzing it?

Thanks!

 

Offline 3DA502

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Re: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review
« Reply #17 on: July 07, 2020, 02:46:07 pm »
EP4CE6 == EP4CE10

they have the same die, So it have 50kByte FPGA RAM
 

Offline iscle

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Re: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review
« Reply #18 on: July 07, 2020, 07:03:00 pm »
EP4CE6 == EP4CE10

they have the same die, So it have 50kByte FPGA RAM

The datasheet says 270Kbits... (Table 1-1)
https://www.intel.com/content/dam/www/programmable/us/en/pdfs/literature/hb/cyclone-iv/cyiv-51001.pdf
 

Offline maginnovision

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Re: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review
« Reply #19 on: July 07, 2020, 08:04:53 pm »
So only ~38k bytes?
 

Offline iscle

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Re: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review
« Reply #20 on: July 07, 2020, 08:10:45 pm »
So only ~38k bytes?

33.75 KBytes, yes  :-\

If only using 1 channel, that would be 0.16875ms storage at 200MSPS (unless I'm missing something here).
« Last Edit: July 07, 2020, 08:18:51 pm by iscle »
 

Offline 3DA502

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Re: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review
« Reply #21 on: July 08, 2020, 02:26:06 am »
itis a trick,the datasheet willnot  tell you
 

Offline iscle

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Re: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review
« Reply #22 on: July 08, 2020, 03:57:54 am »
itis a trick,the datasheet willnot  tell you

Wow, and how do you take advantage of it? I know something similar happened with the flash memory in STM32F103C8T6 MCUs...
 

Offline CChin254

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Re: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review
« Reply #23 on: July 14, 2020, 12:41:18 am »
I did an IC Identification based on the image attached to the original post.
 
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Offline snoopy

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Re: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review
« Reply #24 on: July 14, 2020, 02:12:16 am »
i was thinking, is it useful for a hobbyist like me. even if it is useful for mare 10 mhz only.  :blah: :blah:
can i measure some basic ckts with it like voltage reg, op-amp, and those educational ckts which is in my electronics devices book??

Sure it's useful, just expect a few issues with it. others have reported triggering problems under various conditions, but haven't checked that myself yet.
As I said in the video, perhaps a Hantek USB scope is better value, and cheaper.

I just bought one of these scopes and whilst it's not perfect I do find that I use it when the other scopes are tied up. Because it is portable and easy on the battery it is a great portable scope I can throw in the car anytime. Much cheaper than buying a battery for the TDS3000 ;) Hopefully they will offer some firmware upgrades and allow the auto triggering level detection to be switched on or off. 

cheers
 
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Offline Mr.B

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Re: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review
« Reply #25 on: July 14, 2020, 08:41:06 pm »
Just ordered one.
Should be handy for basic stuff, but the portability is the main reason for the purchase.
Now to see if it is hackable...
Time is the overseer of all things.
 

Offline Martin72

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Re: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review
« Reply #26 on: July 14, 2020, 08:47:11 pm »
I must confess, although this thing is nothing more than a toy, it makes me curious.
After all, they got a support area on their Homepage.
Maybe, firmware updates will be avaible sometimes.

Offline iscle

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Re: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review
« Reply #27 on: July 15, 2020, 03:04:58 am »
I'm planning on rewriting the firmware, adding more features like I2C or UART decoding, and maybe even giving access to a Linux desktop!

I'd need access to the winbond SPI flash contents. That's where the firmware is stored (U-Boot, Linux Kernel and app). If anyone can dump it and post it, it would be great. If not, I will have to wait until I receive mine.

Thanks!
 
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Offline fkfaraz

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Re: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review
« Reply #28 on: July 15, 2020, 10:30:04 am »
hello @iscle

i did not have it but if I did I would certainly do that as I am also interested in a new firmware.
 

Offline iscle

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Re: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review
« Reply #29 on: July 15, 2020, 01:53:44 pm »
hello @iscle

i did not have it but if I did I would certainly do that as I am also interested in a new firmware.

My plan is to improve the UI by building a brand new one with Qt, and also providing more ways of controlling the FPGA (and the ADCs), being able to set the sampling rate and more. For that, the FPGA will need new code too, which I'm looking into (I only know a bit of VHDL when I did some university assignments three years ago).
 
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Offline Martin72

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Re: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review
« Reply #30 on: July 17, 2020, 09:59:49 pm »
Just for fun I´ve ordered one now, should arrive on monday.  ;)

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Re: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review
« Reply #31 on: July 18, 2020, 01:41:25 am »
Max sensitivity of 50mV/div is a crippling limitation.....at least 10x less sensitive than most other basic scopes.  ::)
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Offline snoopy

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Re: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review
« Reply #32 on: July 19, 2020, 01:49:20 am »
For those who want to turn off the auto triggering level in AUTO trig mode the setting is buried away in the system menu of all places. They should have put it in the trigger menu |O

cheers
« Last Edit: July 19, 2020, 01:57:55 am by snoopy »
 

Offline Fungus

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Re: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review
« Reply #33 on: July 20, 2020, 07:05:35 am »
For those who want to turn off the auto triggering level in AUTO trig mode the setting is buried away in the system menu of all places. They should have put it in the trigger menu |O

You only need to turn it off once.

Over in the other thread it's been noted that if you use a x1 probe then pretty much all the problems disappear due to the extra capacitance.  You're limited to about 30MHz, sure, but all the artifacts disappear.

I think it would be cool to find the optimum capacitance to maximize bandwidth, solder a capacitor of that size into the front end, go back to using x10 probes.

This simple mod would mean you can rely a lot more on what's being shown on screen being correct. Anybody up for doing it? (I don't have one of these yet, so...)

Maybe there's a 'hacking the Fnirsi Tablet Oscilloscope" video in this for Dave.
« Last Edit: July 20, 2020, 07:09:35 am by Fungus »
 

Offline Fungus

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Re: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review
« Reply #34 on: July 20, 2020, 07:07:07 am »
Max sensitivity of 50mV/div is a crippling limitation....

Not for an awful lot of scenarios, it isn't.


Yeah, we know, we should all buy Siglents instead.

 

Offline tautech

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Re: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review
« Reply #35 on: July 20, 2020, 12:20:54 pm »
Max sensitivity of 50mV/div is a crippling limitation....

Not for an awful lot of scenarios, it isn't.


Yeah, we know, we should all buy Siglents instead.
FFS get real Fungus !
Put a 10x probe on the POS and you're limited to 500mV/div max sensitivity which in the real world (maybe not yours) is seriously limiting.
Really what planet are you on ?  :-//
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Offline Fungus

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Re: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review
« Reply #36 on: July 20, 2020, 02:28:27 pm »
FFS get real Fungus !
Put a 10x probe on the POS and you're limited to 500mV/div max sensitivity which in the real world (maybe not yours) is seriously limiting.
Really what planet are you on ?  :-//

Oh, I forgot about that. OK, 1x probes it is. :-)

Has anybody measured the -3db point with 1x probes? I can't find it in either of the threads.



 

Offline Martin72

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Re: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review
« Reply #37 on: July 20, 2020, 03:53:51 pm »
Can do it in the next hours.

Two threads parallel...which will "win"  8)

Offline Fungus

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Re: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review
« Reply #38 on: July 20, 2020, 04:17:59 pm »
Can do it in the next hours.

Two threads parallel...which will "win"  8)

The other thread is busy dumping the firmware...  :popcorn:
 

Online 2N3055

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Re: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review
« Reply #39 on: July 20, 2020, 06:55:41 pm »
In 1x probes alone will have 5-10 MHz bandwidth.. Scope's bandwidth of 1X/10X probes is rated at 10x
So for best bandwidth you need to put probes in 10X..
 

Offline Fungus

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Re: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review
« Reply #40 on: July 20, 2020, 07:10:12 pm »
Can do it in the next hours.

Two threads parallel...which will "win"  8)

The other thread is busy dumping the firmware...  :popcorn:

Edit: No, they won. It's over 30Mhz.


No, scratch that. That measurement was with "alligator clips" so it won't have the capacitance of a 1x probe.
« Last Edit: July 20, 2020, 07:13:25 pm by Fungus »
 

Offline Fungus

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Re: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review
« Reply #41 on: July 21, 2020, 08:10:26 am »
Hopefully they will offer some firmware upgrades and allow the auto triggering level detection to be switched on or off. 

You mean this?

[attachimg=1]
 

Offline pplaninsky

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Re: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review
« Reply #42 on: July 26, 2020, 05:12:38 pm »
Is this usable to make floating measurements?
« Last Edit: July 26, 2020, 05:51:18 pm by pplaninsky »
 

Offline Fungus

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Re: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review
« Reply #43 on: July 26, 2020, 05:46:04 pm »
Is this usable to make floating measurements?

It only does floating measurements when it's on battery power.  :)
 

Offline pplaninsky

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Re: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review
« Reply #44 on: July 26, 2020, 05:52:09 pm »
Battery power should be OK, here is what I am having in mind.

In many old 20MHz CROs, there is electrostatic CRT and the cathode is driven at around -2KV DC, whereas a lot of the driving signals has differential voltage of 20 V DC or less.
Measuring that with an oscilloscope referenced to ground will produce a big bang or at best the GFCI will trigger.
A 2KV to ground (common mode range) differential probe is a rare and expensive device.
« Last Edit: July 26, 2020, 05:54:22 pm by pplaninsky »
 

Online 2N3055

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Re: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review
« Reply #45 on: July 26, 2020, 06:15:18 pm »
Battery power should be OK, here is what I am having in mind.

In many old 20MHz CROs, there is electrostatic CRT and the cathode is driven at around -2KV DC, whereas a lot of the driving signals has differential voltage of 20 V DC or less.
Measuring that with an oscilloscope referenced to ground will produce a big bang or at best the GFCI will trigger.
A 2KV to ground (common mode range) differential probe is a rare and expensive device.

230€

Micsig DP20003 100MHz
Maximum Differential Test Voltage(DC+AC PK-PK)           560 V (200 X)/ 5600 V (2000 X)
Maximum input common mode voltage(DC+AC PK-PK)   560 V (200 X)/ 5600 V (2000 X)

 

Offline pplaninsky

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Re: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review
« Reply #46 on: July 26, 2020, 07:38:33 pm »
Thanks for the hint!
However, the specs state.

Maximum input common mode voltage: CAT II 1000V

Isn't that unsuatable for differential rails that are 2KV referenced to ground?
Otherwise, not that this is a cheap probe 230 EUR - but is somewhat acceptable comparead to thousands of EURO.
 

Online 2N3055

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Re: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review
« Reply #47 on: July 26, 2020, 08:15:13 pm »
Thanks for the hint!
However, the specs state.

Maximum input common mode voltage: CAT II 1000V

Isn't that unsuatable for differential rails that are 2KV referenced to ground?
Otherwise, not that this is a cheap probe 230 EUR - but is somewhat acceptable comparead to thousands of EURO.

No not cheap, but affordable.  and decent qualitiy.
CAT II 1000V is referring to protection when working on higher energy circuits. For your use 5600 V P-P max apply..
 

Offline theoldwizard1

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Re: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review
« Reply #48 on: September 11, 2020, 03:07:19 pm »
I just re-watched Dave's review of this 'scope.  His conclusions are spot on.  If you call it a 200MS/sec/channel 'scope (assuming they are actually gathering data using an out of phase clock per channel) it is not a bad 'scope for the price.  If they could fix some of the software/UI issues this would be a really decent 'scope for the money !

Sadly, I don't expect any firmware upgrades, at least in the near future.

There are ADC that can do 1GS/sec in a similar price range as the ADC9288 but how how good is that front end ?  Of course they are probably using a clone that they can get for a few pennies.
 

Offline piyush

  • Newbie
  • Posts: 1
  • Country: tw
Re: EEVblog #1317 - $140 2CH 100MHz Fnirsi Tablet Oscilloscope Review
« Reply #49 on: Yesterday at 04:15:56 am »
Hello Friends,

I am interested in redoing UI with QT if firmware is usable.

Besides I order one but received with Chinese language, I talk to supplier then they said can't change language, I also ask to provide firmware to upgrade but they can't, Can any one please help me to provide dd image of English version sd card ?

Thanks


 


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