Questions tagged [logic-analyzer]
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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Help identifying protocol for Midea AC daughter PCB communication
I have a basic Midea AC unit that lacks Wi-Fi connectivity, and I'm interested in making it smart. It consists of a main PCB, which I prefer not to tamper with, and a smaller daughter PCB responsible ...
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How to identify protocol of unknown 7 segment display chip?
I'm trying out logic analyser with digital clock I have laying around. The clock uses 7 segment display (4 digits) and consists of two parts: display with unknown chip inside and main board with two ...
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Help decoding unknown data stream
I'm currently diving into the task of cracking the data stream protocol for a generator control system. There's this setup with a control box sitting next to the generator, and a remote switch in the ...
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Decoding Bit Rate Information for an LED Project Using a Logic Analyzer
I am currently working on a project where I'm trying to understand and decode the bit rate information being sent to an LED. I purchased an LED for my backyard that can be changed to different colors ...
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Is it possible to measure analog signals using cheap logic analyser? [closed]
I am using cheap logic analyzer with 8 channels, 1 CLK channel and GND. I am also using Logic2 software by Saleae and would like to know if it is possible to capture analog signals, like Sin wave? I ...
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How do I figure out what these ack signals mean?
I am trying to get the data from a rangefinder and an HT1621 LCD driver. I have set up a logic analyzer that uses an I2C analyzer. I am receiving all of these signals but frankly don't know where to ...
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MSP430 I2C communication no ACK
I'm trying to get I2C working with the MSP4302231 and had and still have some problems. The main problem is that I don't get an ACK from the slave to which I send its address on the I2C bus. Noticed ...
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CAN communication in dsPIC33CK64MP508
I tried to transmit data using CAN communication in dsPIC33CK64MP508. I use MCC for configuring CAN in dsPIC33CK64MP508. I set the bit rate to 500 kbps. I just transmit two data bytes (0x41 and 0x42) ...
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CAN-Bus Message confusion
Can anyone tell me what the difference between these two sets of CAN Bus messages? This is from the manual of a Power Drive Unit (PDU) in the Cargo Handling System of a 747F (UPS Freight). This is the ...
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MPU6050 ESP32 No Acknowledge
I am struggling to get an acknowledge from the MPU6050 using ESP32 with Arduino framework. I am unable to derive if the problem is hardware or firmware.
I have copied Sparkfun's breakout board ...
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Signal not Showing State Changes on Intergrated Logic Analyser (Vivado)
I have been using the Integrated Logic Analyser (ILA) on Vivado 2021.2 to log some signals from a RISC-V processor running on an FPGA (BASYS 3 FPGA development board).
The signals I am monitoring are ...
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How to record analog signal of a RS485 bus with a pocket Oscilloscope / Logic Analyzer with ADC (limited input voltage range with voltage divider?)?
I need to debug an RS485 bus (record analog signals) on a remote installation with a pocket Oscilloscope or Logic Analyzer. Can I simply use a voltage divider to bring down the RS485 signal to within ...
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STM32 CANTX line always idle
I'm trying to learn about microcontrollers in general and at this point I'm trying to learn about the CAN bus standard by using it with an STM32 MCU in a NUCLEO-F767ZI board.
For that end I want to ...
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How to repeat trigger in a logic analyzer
I'm using OpenBench Logic Sniffer (HW) with Sigrok PulseView (SW) to reverse engineer some binary UART communication between a control panel and the device. The trouble is that I can capture only 24k ...
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Signal identification: What serial protocol does my desk use?
Can anybody identify what kind of signalling protocol this is?
I'm sampling at 2 MHz. Here's the first falling edge of the signal, with a default UART protocol decoder for reference (8 bits, no parity,...
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K-line sniffing problem
I'm facing a problem while trying to check the communication between two devices talking over k-line ISO 14230-4 KWP protocol.I have two master devices and one slave device (i'm calling them master ...
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USB-PD Packet Analyzer
I'm trying to design a USB-PD equipped board, and currently evaluating this Maxim eval board. I'm plugging in an USB-PD Charger and unable to see any PD activity when measuring with this sparkfun ...
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Identifying Protocol Using a Logic Analyzer
I used a logic analyzer to read the data line from a small camera battery and would like to understand the authentication my camera is doing to the battery over the one data line. Is there any way to ...
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Reading CAN Bus without a ground [closed]
I need your help to find a transceiver that can read or write data on a CAN bus using only CANH and CANL, without the ground of the System I am connected to.
Just to be clear, I need something that ...
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How to probe UART pins of a phone?
I'm gonna try to probe this phone for UART pins: https://www.youtube.com/watch?v=scsAlvMie1M
I have a cheap logic analyzer and just bought really pointy probing pins (waiting to arrive), I also have ...
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Logic analyzer gives me much more pulses than expected
Let me start the question by saying that I am using a logic analyzer for the first time, so I am probably doing something wrong.
I sniffed the signal that goes to a speaker. The signal is probably PWM....
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SD Card Not Responding To Command 0 In SPI Mode
I am attempting to communicate with an SD card in SPI mode. I am running at 133kHz. I first send a hundred or so clock pulses over the course of a millisecond with the chip select signal high. I then ...
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LHT00SU1 logic analyzer clock generator
I was using a LHT00SU1 logic analyzer and according to this it should have the capability to produce a variable frequency signal (i assume through the CLK pin).
Using pulseview with fx2lafw firmware I ...
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HX711 zero factor
I have three load cells (YZC-1B). These load cells' capacity is 50 kg. I guess I use Bogde's HX711 library.
In monitor, the zero factor for the first two load cells is 8,000,000, but for the last load ...
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Help explaining how signal is measured with no ground reference
The picture shows a car LED module that is controlled with a pulsed +12 V to change its brightness. I want to measure the range of this PWM using a cheap logic analyzer that I have but it can only ...
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How to read "inverted" uart signal
I have am experimenting with an MDB device. I have a simple setup, with an MDB master, and my own NXP EVK board which acts as slave.
I started with just a logic analyzer, to verify that I see ...
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Flash SPI communication doesn't work without osciloscope
We are using W25Q128JV Flash IC in conjunction with nRF52 SoC.
Datasheet of flash: https://www.winbond.com/resource-files/W25Q128JV%20RevH%2003102021%20Plus.pdf
We face following issue: SPI ...
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Sniffing a CAN Bus with strange behavior
I want to sniff data from a CAN Bus where are nodes using these parts:
1 - 18F24K20 - Microcontroller
2 - VP233 - CAN Transceiver
3 - 78L33A - Voltage Regulator
These nodes are sensors that detect ...
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RS485 Reverse Engineering
I'm reversing a RS485 comunication.
I have purchased a logical analyzer for reversing and sniffing the data packets.
But i have a problem, don't knowing the exactly comunication parameters i can't &...
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What is this Digilent Analog Discovery device doing in this experiment?
I'm a novice to electronics, and I was wondering if someone would clarify an experiment I just witnessed. A photodiode was set up to receive some signal. This signal is then read by a transimpedance ...
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What logic analyzer specifications are needed to inspect HDMI 720p 60 Hz?
I would like to inspect the audio data islands of a 1280x720 progressive scan 60 Hz HDMI signal. I simply want to view these data islands to see exactly when audio data begins to be transported in the ...
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Chipscope ILA unable to capture signals correctly
ALL the ILA modules that I am having now do not work .
I mean they failed to even capture the user-assigned 'clk' and 'resetn' signals. Why ?
Note: the PCB schematics could be found here
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Soldering connector on PCB to connect to logic analyser or scope
When it comes to digital circuits, it is often important to get certain internal design signals to an I/O pin and then view it on scope. This is in-spite of all the other techniques that exist to ...
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High Speed Digital Signal Measurement
What is the best way to measure a 40 MHz clock signal?
I tried using an oscilloscope with an 8pf passive probe, and the signal was unrecognizable. Would a logic analyzer work better in this case?
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Logic analyzer interference when analyzing SPI bus
I'm trying to analyze SPI EEPROM with a logic analyzer.
The logic analyzer is connected to the spi eeprom via ~20cm wires + SOIC8 Testing Clip (Only MOSI/MISO/CS/SCLK/GND are connected to the logic ...
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CAN-BUS line goes bus off state at high temperature(70C°)
I have a CAN-BUS line communicating at 50kb/s speed. There are only 2 products communicating with each other on the CAN-BUS line. One of these products has the STM32L496RGT MCU (the clock speed of the ...
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How to find and decode a particular protocol
I'm trying to understand what protocol is used on a particular device in order to decode it and send custom values.
So far I was able to record the data with a logic analyzer but couldn't figure out ...
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CAN Frame Malforming on Oscilloscope
I have a working 500kbps CAN bus between an Arduino Uno and a RaspberryPi. Both are connected to MCP2515/TJA1050 boards from Amazon and communicating over SPI. The RaspberryPi dumps the CAN data via ...
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Logic Analyzer with ground probe missing
I'm playing around with a USB logic analyzer (DSLogic Plus) to look at some RS232 signals. Everything seems to be working fine, but I just noticed that the probe to ground wasn't connected properly. ...
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Feasible to capture data to/from a 1970s RAM chip?
I have a 1978 Bally Playboy pinball machine. The processor is a 1Mhz 8-bit microprocessor Motorola 6800. I would like to build a way to extract/watch game state from outside of the machine. The best ...
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How to identify an unknown protocol with a logic analyzer?
I have this Inbras electrolyte analyzer, a rebranded version of the same device manufactured by Diestro. It uses a PIC18F87K22 (master) which communicates with the sensor using a PIC12F629 (slave) ...
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What sample rate do I need to analyze usb 2 with a analyzer?
What is the sample rate needed for a logic analyzer to be able to analyze a 480 Mbps USB 2 bus?
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Purpose of inverted channel for UART bus communication
I'd like to understand the purpose of an inverted logic channel on device-to-device communication that is being done via UART.
For some background - I'm trying to reverse engineer this device-to-...
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Analyze protocol used for Futaba VFD display, 3 data pins
I take apart a Samsung SMT-C7140 HD Unit (made obsolete by cable company, a shame) and found a nice display that I could probably reuse. It is a Futaba GL07-00006A (13-BT-246GINK). I tried to find the ...
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CAN bus malfunction on STM32F3
I create applications for STM32 F303RE for communication with the instrument panel. I managed to connect everything but I have some problems. I'm not sure if it's due to bad code or good performance. ...
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NAK in CAN bus for STM32F3 uC
I have a problem with the NAK on the CAN bus. On STM32F303RE I wrote a code for communication via CAN bus with car dashboard (Instrument Panel Cluster). The communication works, I manage to receive ...
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Building analog representation out of digital lines in PulseView
I am not sure if I am posting this in the right forum so if not, please let me know so I'll can post it somewhere else.
I want to monitor an analog signal but I only have a logic analyser at home, so ...
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Oscilloscopes and Packed Two-Layer PCB boards? (“Operating Table” PCBs)
I have recently completed a very complicated 2-layer circuit board. Every square mm has a component in it, two of the sides undergo edge plating, and one is riddled with right-angled connectors.
I ...
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I want to use logic analyzer to learn remote control IR codes
I've just ordered this generic logic analyzer (didn't get it yet).
Does the specs (channels/speed/accuracy) of such a cheap analyzer can be used to analyze IR remote control code sequences so I'll be ...
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Sandisk micro sd card not detected. How to diagnose the problem without knowledge about the sd card protocol? [closed]
Seems to be a common problem with Sandisk micro sd cards.
Just a little before or after the warrenty period, the micro sd card suddently stop to be recognized. I mean phones and external card reader ...