Questions tagged [ttl]
Transistor Transistor Logic. Logic circuits built from bipolar transistors and resistors.
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Serial communication between raspberry and laptop not giving right values
I want to communicate between a Raspberry Pi 3 model B and a laptop using a USB to RS-232 cable and this RS-232 to 3.3V TTL converter via the serial module in Python:
GND is connected to board pin #6
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TTL gate characteristics
In case of BJT for example, the input characteristics can be described with \$I_B=f(V_{BE})\$ and output characteristics with \$I_C=f(V_{CE})\$.
How can the input and output characteristics be ...
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Are pull-up resistors mandatory for inputs on modern parallel ports?
Here I go again testing more circuits on two computers with each reporting completely different data yet I feed the same data in.
Now this time, the data coming back is all logic highs on my laptop ...
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Driving a ThorLabs piezo controller with TTL external input
I am trying to drive a ThorLabs piezo controller (https://www.thorlabs.com/newgrouppage9.cfm?objectgroup_id=2421&pn=KPZ101) with an external +3.3V TTL signal provided by a microcontroller (using ...
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Clear D flip flop internal logical scheme
I am new in this community and also in logic circuit design and digital electronics. I couldn't find the logical design on the internet for the following D flip flop and i would like to know how it's ...
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Are differential line drivers "active" circuits?
Some quadrature encoder datasheets describe their outputs as either Differential Line Driver or Line Driver. On closer inspection of the diagrams, they appear to be the same thing (differential line ...
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Why does a 74LS189 RAM chip light-up an LED connected to its re-inverted output when data word is HIGH while a 7489 RAM chip cannot?
I have thought on it a lot and summarizing my confusion here. I have two SN7489N chips whose Ioh is 20uA (not sufficient to light-up an LED). Correct me if I'm wrong that Ioh is the maximum current it ...
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Does anyone knows the SmartGen LINK Port protocol?
I need to replace an SG72A controller in a machine, I would like to make a cable or small component to It, because I have no time to wait for this to came from China to Brazil.
I didn't found any ...
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A question about max TTL input of a converter device
I have a programmable f/I converter which can be modified for various types of inputs and outputs. They have also a more detailed manual. I read them and learned how to configure and set this device. ...
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How can I output to one of 4 different outputs without using a demultiplexer?
I do not have a demultiplexer available, so I need a substitute. I have a TTL signal and I need to output the signal to output 1, then output 2, then output 3, then output 4 in sequence, meaning that ...
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Changing from 8 channel to 16 channel. Does change in voltage input affect upgrade?
I am going from a Numato 8 channel GPIO to a Numato 16 channel GPIO. The 8 channel I/O pins support 5V TTL signals but the 16 channel I/O pins support 3.3V TTL signals.
If the input to the I/O of the ...
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Using RXD to generate Audio signal and serial communication all connected to each other
I'm using RXD to transfer audio to an amplifier (1) and TTL communication with USB/TTL converter (2) for communication. Everything works but I can not get maximum output from the amplifier. When I ...
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What would be logic value of high impedance TTL output connected to LED
Suppose a TTL output in high impedance is connected to a LED, which is also connected to a resistor, which is then connected to ground. No circuit interferes between TTL output and LED, between LED ...
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Definitions of Serial TTL UART MCU acronyms
I was looking for a comprehensive list of terms and acronyms concerning serial peripheral communication including their descriptions and, crucially, how they relate to each other. Since this site ...
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