A logic analyzer is an electronic instrument which visualizes a set of digital signal across time. It can only display logic levels and their transitions, not analog levels.

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79 views

Sniffing a proprietary data line at 47.5V

I need to sniff the physical layer of a proprietary data line with a logic analyser, but my analyser is limited to 5V input. Unfortunately the line runs at 47.5V, which would fry everything. I ...
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0answers
33 views

OBD2 CAN digital analysis yields signal only on CAN Low

Since I don't seem to find the OBD2 CAN specification anywhere on the internet, I am trying to reverse engineer the signaling done so that in the end I can develop a piece of hardware that will act as ...
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1answer
80 views

Logic analyzer: multiple circuits, one ground

I will receive soon my first logic analyzer but I'm wondering something: There's only one ground on the analyzer. What if I want to measure at the same time two circuits with two separate power ...
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101 views

Debugging VGA signal

I have tried to use my Open bench logic sniffer to capture data from a VGA output. I'm pretty sure I understand how the waveform should look, but I not getting consistent data. It feels very shaky to ...
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1answer
67 views

Bus Pirate as a logic analyser [closed]

I am planning to buy a logic analyzer to see if my SPI lines actually output data correctly. (Actually to check if they output data at all since when I put it on a scope I could not see much). I am ...
2
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1answer
104 views

Analyzing 4-pin data port to determine protocol

I have a Solar controller for my pool, it controls the pump and actuator for routing water onto the roof to heat it up, when required. The controller knows the pool and roof temperatures, as well as ...
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1answer
54 views

Quartus II - SignalTap II Getting the Period of Sampled Data

I am working on a VHDL project where I am trying to make an LCD controller. I have been trying to get the period of my scaled clocks using Signal Tap, however the time bar does not show the time ...
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1answer
121 views

Why I cannot see SPI signal properly with oscilloscope?

When I monitor a SPI bus with only one probe, I see such output when data is transferred. I know that I need to use a logic analyzer to monitor the SPI, but I wonder why I see such signal that ...
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2answers
193 views

5 V to 12 V transceiver chip / hardware

I am looking for a way to connect my logic analyzer (an inexpensive Saleae which is intended for 1.8-5V targets) and a couple of other pieces of analysis equipment to a digital source with signals in ...
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2answers
1k views

How to use USBee AX logic analyzer under Linux?

I've got clone of USBee AX logic analyzer, to play with one and see if I need a device of such type at all. Unfortunately, I haven't found any Linux software that supports one. I have tried Sigrok, ...
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4answers
824 views

Using Pickit3 as a logic analyzer

I need to sniff some legacy SPI hardware and at hand have a Pickit3 and lots of PIC18F2550/4550. While there is no project out there that builds a logic analyzer out of a PIC18F2550/4550 (I will be ...
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2answers
1k views

AVR interrupt service routine not executing as fast as expected (instruction overhead?)

I'm developing a small logic analyzer with 7 inputs. My target device is an ATmega168 with a 20MHz clock rate. To detect logic changes I use pin change interrupts. ...
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2answers
387 views

RS 232 serial sniffing

We have a task in hand to sniff a RS232 protocol in a certain industrial automation setting(we have been asked to do this legally by the manufacturing company itself). We are planning to send a ...
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1answer
227 views

Open bench logic sniffer Not working

I am using my openbench logic analyser for the first time in a real project. I am not getting valid captures though. I have the latest client off dangerous prototypes website they recommend for mac. ...
2
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2answers
445 views

Scanalogic DIY Logic Analyzer, Extending Sample Time

I just completed my build of the Scanalogic DIY logic analyzer. It's working great, but I am noticing something odd about it. This question will likely only make sense to someone who has used or built ...
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2answers
196 views

Logic Analyzer Basics

I am buying a second hand logic analyzer (Agilent 1661A) and I see the terminology such as the following: 100MHz State Speed Maximum Conventional Timing Rate: 250 MHz full channel, 500 MHz half ...
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2answers
160 views

Buspirate Logic Analyzer Mode Issue

I am new to the logic analyzer mode of Bus Pirate, so to play with it i connected channel 3(MOSI) line to the output of an TSOP1708 IR decoder to see if the capture came through. However when I ...
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0answers
82 views

Logic Analyzer / Oscilloscope Suggestions [duplicate]

Possible Duplicate: Beginner's logic analyzer? I am a beginner in electronics. Been tinkering with micro controllers for about 2-3 months now. At this point I find the need for a logic ...
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1answer
112 views

Sampling 133MHz bus with OWLS Logic Analyser

The OWLS specs state that it can operate in two sampling modes: 200Msps captures up to 100MHz waveforms on 16 channels 100Msps captures up to 50MHz waveforms on 32 channels Does this mean that ...
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2answers
602 views

Which tools do you use to analyze waveform data from simulation or logic analyzer traces?

I need to save Xilinx ChipScope waveforms for later review/analysis with my co-workers. Wikipedia provided a handy list of waveform tools but I am looking for user feedback on some of the strengths ...
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3answers
239 views

How to hook up an FPGA to a component that has a different power supply?

I recently programmed my FPGA with a logic analyzer core for the purpose of reverse engineering a crappy modem I have. I found on it what I think is either JTAG or TTL-serial pads. There are 4 blank ...
3
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3answers
405 views

What is going on with these SPI transmissions?

I just got a Saleae logic analyzer and I'm using it to hack a Guitar Hero drum set. The main board within the drum set talks to another sub-board using SPI. When I tap into the conversation, I see ...
2
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4answers
374 views

Why buy protocol analyzer modules for an oscilloscope?

Scopes with logic analyzer inputs often have optional add-on modules that let them decode various serial protocols: SPI, RS-232, I²C, CAN, etc. Tek and Agilent want around US $700 per protocol family ...
3
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1answer
244 views

GND/Vss of 2 circuits with independent power supplies, and usage of scope/logic-analyzer

Probably an elementary electronics question. If I would like to trace waveforms from 2 different circuits with independent power supplies, s.a. an RF transmitter which uses a 9V battery and the RF ...
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2answers
228 views

Noisy data line clears up on wiring up multiple output pins of uC to Logic Analyzer

Some people reading my question might be familiar with a string of questions (latest being this one) where I have been asking about how to decode data from an ISM-band ASK/OOK type RF receiver module. ...
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3answers
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Using Logic-Analyzer to reverse-engineer ISM-band ASK/OOK encoding, possible?

Is it possible to use a Logic Analyzer (such as this one), to determine the waveform s.t. on the DATA out pin of an ISM-band ASK/OOK (315/433.92MHz) RF module, in turn to decode it's encoding scheme. ...
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2answers
218 views

Protocol Analyzer in software?

I'm looking for an easy solution to identify data formats, protocols. I have an outdoor temperature - humidity sensor which is connected to my HVAC system. I want to decode the data coming back from ...
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3answers
145 views

Recommendation for a USB digital simulator

It's becoming quite frequent to me having a new digital subsystem which I want to test in isolation before trying to make a prototype circuit. I've been using the digital analyzer by Saleae for ...
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9answers
1k views

Is a single channel oscilloscope enough for most purposes?

So I have spent the past two days going through various budget oscilloscopes and checking their specs VS price. Most of the information I have gathered has been from here and I am almost sold on an ...
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2answers
1k views

Logic Analyser for Mac environment

I am wondering if anyone can recommend a logic analyser for a Apple Mac environment with similar features as the SCANALOGIC 2 PRO around the same price would be great as well. or some thing that is ...
5
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3answers
687 views

Openbench Logic Sniffer setup

I finally broke down and bought this board: http://hackaday.com/2010/02/28/open-source-logic-analyzer-2/ It "seems" like it would be really helpful, the problem I'm having is getting it setup, I am ...
9
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8answers
2k views

Best tools to debug simple digital circuits?

I am a professional software developer who is used to the luxuries of integrated debuggers. For a while now, I have been experimenting with the Arduino platform. However, I find that attempting to ...
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3answers
426 views

Passive listening to USB communication

Is it possible to passively listen on low speed USB communication? Suppose I connect a logic analyzer to D+ or D- line, will I see a valid data?
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4answers
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How to reverse engineer I2C and SPI protocols?

If I have an unkown device which talk I2C or SPI how can I reverse engineer the protocol. Basically I am looking for something similar as snoop or tcpdump. For software Mac is preferred but can also ...