All Questions
Tagged with logic-analyzer digital-logic
16 questions
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Questions About Logic Analyzers: Mixing Digital and Analog Signals
I recently became interested in logic analyzers, particularly those like the Saleae models that can sample both digital and analog signals on the same channel. I understand that for analog signals, an ...
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1
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451
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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 ...
- 155
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2
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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....
- 1,399
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5
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912
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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 ...
- 2,311
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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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- 399
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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 ...
- 1,377
3
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1
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610
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What effect does a logic analyzer probe have on a circuit?
I have an MCU controlling a LED sign. This sign speaks the HUB75 protocol, which is essentially a large shift register. Being a shift register, this requires a clock signal to be generated, which the ...
- 131
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Why signals occupy small portion after being scaled and how to change it?
I am a newbie and try to understand why signals watched on logic analyzer shrink on screen when resolution is changed (as on the pics) so that they occupy a small region on the screen? It'a a ...
user195443
5
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2
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443
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What kind of serial communication is this?
I am trying to reverse engineer a serial communication between to microcontrollers (1 device & 1 microcontroller on a board). One MCU validates the other MCU and I want to crack the validation and ...
- 275
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1
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141
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Minimize Two bit Multiplication in Binary function
the input are X=(x1,x0), Y=(y1,y0).
the output is Z=(z3,z2,z1,z0).
the component: Z=X*Y .
I got these simplified expressions by Karnaugh maps:
(* = AND / + = OR / ~ = NOT )
z3=x1*x0*y1*y0
z2=x1*(...
- 1
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1
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Help me add outputs from a two 3 to 8 decoders
I have built two 3 to 8 decoders, so that I can get an octal output 0-7 from each.
Now, I need to be able to add these outputs to determine wether a number is greater than 7 or not.
I have tried to ...
3
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1
answer
1k
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Reverse engineering 7 segment display
I ran into a problem with one of my hobby projects and at this point I need some help. I'm attempting to sniff the signals going into a 7 segment display and use them for a purpose.
The display is a ...
- 31
1
vote
0
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276
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How to control chip select and Load DAC signals for a DAC chip?
I have a DAC7643 (Texas Instruments) - 16-Bit, Dual Voltage Output
DIGITAL-TO-ANALOG CONVERTER
I have been mostly unsuccessful with controlling the CS and LDAC signals. I have simulated a circuit ...
- 11
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1
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331
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Combining 8 digital signals
I am building a 8 channel 50MHz PC based logic analyzer to learn a bit about digital design. I am currently having trouble at the trigger portion of it, more precisely generating the signal that will "...
- 2,007
3
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3
answers
1k
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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 ...
- 2,191
26
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15
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Beginner's logic analyzer?
Can anyone recommend a low cost or DIY buildable logic analyzer?
Mostly, it would be for debugging serial protocols (SPI, I2C, RS232) at low voltages.