LA104 Pocket logic analyser

[PinheadBE]

Hi,

There's a new kid in town: the LA104 is presented as a 100 MHz sampling 4-channels I2C/SPI/UART pocket logic analyser for under $100.
Available from e-bay and the usual chinese sellers

Has anyone got a chance to grab one of those yet and examine that puppy ?

P-P-P-Pleeeeeease tell me it's worth its money..... 

[PinheadBE]

Here's a user manual.   It's in chinese, but the specs figures are easily understandable.
http://www.minidso.com/forum.php?mod=viewthread&tid=3194&extra=page%3D1

I feel little enthusiasm here.... 

[MiniWare]

If you can write a LA104 review, I can post you with free.

[PinheadBE]

I'm afraid I don't have the expertise to do that.

Besides, I am not a YouTuber....   sorry.....

[PinheadBE]

Sorry to bring this up again....
.... but doesn't this spark any interest at all ?

[gabonator]

Hello guys,

I was lucky and have got the opportunity to play a little with the LA104 analyser. Hard to say if it is worth the money with current firmware, but with the help of community it can become really very sophisticated laboratory equipment worth twice the money or even more. The company producing this unit released source code of their firmware, so it is quite easy to add there new features. You can consider it as development board with FPGA, ARM M3 CPU running at 60MHz, lcd display, 8 IO pins and USB connection. With a little effort you can run there any of your favourite arduino programs.
If you expect to get full featured laboratory grade logic analyser, you could be disappointed. It seems that it can be now used just to graphically review 4 digital signals with possibility of decoding UART or SPI. I am bit sad, because 4 bits is usually too little to do some serious analysis.

To sum it up:
Pros:
  - partially open sourced (FPGA code was not still released)
  - supports SPI/UART decoding
  - trigger pattern
  - 10nS sampling resolution
  - 320x240 16bpp lcd display
  - can run arduino snippets
  - battery powered
  - 8MB internal storage for whatever you want (more applications, signal snapshots, etc...)
  - small portable design
  - great for educational projects
  - great for in field measurement
  - powerful enough to control 2 axis CNC or play midi instrument
  - IO pins could be expanded by external circuits, but at the expense of losing sampling speed
  - if you can do some basic programming, you will love this unit

Cons:
  - only 4 input channels (the other 4 pins are currently used for PWM/UART/SPI/I2C signal generation)
  - takes some time to get used to the controls (only 2 rotary encoders and 4 buttons)

If you want to know more:
  https://github.com/gabonator/LA104

[PinheadBE]

Impressing job, Gabonator !

In fact, I am in need of a portable logic analyzer that can be used on the field, when transporting a PC and/or an oscilloscope is not possible.

Regarding the firmware improvement, I would like to see if it could be possible to add more decoders, such as USB, 1-Wire, CAN....
Apparently, there is plenty of memory available !

Thanks for having put all your research online ! 

[gabonator]

Hello guys,

I would like to share my latest project with LA104 - LA104 as radio signal analyser with a ton of features:
- useful for capturing weather station signals / all wireless devices using OOK/ASK modulation
- synthesizing fake packets and sending them back to weather stations
- capturing short range wireless key signals, decoding, storing...
- replay attacks (unlocking a car)
- web usb analyser running in web browser with RTL433 library (very popular library for decoding ook modulations)

https://youtu.be/Gwyi00NKBNg

[gabonator]

Finally after two years of development I reached a point where it is possible to make full review of the OS for LA104:



Maybe too late for ordering it as Christmas gift, but I hope you will like it

[YurkshireLad]

Is the LA104 good enough to debug the protocol/logic of a sensor like the DHT11 (temperature/humidity)? Code that used to work is now reporting "nan" from my DHT11 so I need to see if it's broken or not.

If not, is there something equivalent in size and price?

[robca]

Given how slow the DHT11 protocol is, even one of the ubiquitous ~$10 24mhz  8 channel Saleae clones (with Sigrok, so as not to pirate the Saleae code) would be overkill

A DHT11 costs less than $2, so spending $100 on a logic analyzer to see if a $2 chip works seems excessive $10 might be more in line with the needs

Many Arduino libraries have problems with the DHT11, and in many cases the problems are version specific. So you might want to try different libraries and/or different versions of the library to see why the problem happens

[YurkshireLad]

Thanks robca. I've tried a couple of other libraries, and they all gave the same result. I know it's overkill buying an analyzer instead of a new sensor, but I will probably use the analyzer anyway. So.... more tools to hide from the wife! 

[robca]

My usual advice for tools like a logic analyzer, is to get something cheap (as long as it's functional) until you know more about what you need in that tool and can spend more. While that might not work for an oscilloscope, where the very cheap ones are too limiting, the Saleae clones are not a toy and are surprisingly powerful for the price

I have used a Saleae 24MHz 8 channel for years without problems, and recently upgraded to a DSLogic. While the DSLogic is much better, for simple and slower protocols, the Saleae is more than good enough and comes with the same protocol decoders as DSLogic (both are based on Sigrok).

If you use Sigrok with the Saleae clone, you get the DHT11 protocol decoder https://sigrok.org/wiki/Protocol_decoder:Am230x

So, unless you have a very specific need to have a portable logic analyzer, I would highly recommend a Saleae clone (Amazon, eBay,  Aliexpress). For $10 you get a ton of value, and works for pretty much anything you can do with an Arduino. If one day you discover you need something better, well, consider those $10 a learning opportunity