A device which includes a central processing unit (CPU), memory, and (generally) an assortment of I/O peripherals (UART, ADC, DAC, general-purpose I/O, I2C, etc.) in a tightly-coupled standalone package.
1
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2answers
86 views
How does a specific pin in a port change its state (PIC Microcontroller)? Software vs Hardware
How does, for instance PortB.B0 = 1; command change the state of a specific pin in a microcontroller.
Microcontroller usually has a 8 bit data line, meaning it will write and read from the entire ...
0
votes
1answer
60 views
UART give garbage values after waking up from sleep(arduino)
I've made a arduino clone which has a PIR sensor, I intend to run it on 2AA, I'm using LT1302 boost converter, because the PIR sensor works at 5V, if motion is detected the message will be sent to my ...
2
votes
1answer
47 views
Triac and Optoisolator not turning on lightbulb
I'm trying to switch on a lamp using a microcontroller. I've wired the schematic below using a 5v power supply instead of the microcontroller for now and the first time I turned on the lamp the ...
0
votes
4answers
166 views
What are the odds of a miscalculation in an Arduino?
I am running an experiment using an Arduino that requires several million calculations per second to be performed by an Arduino. I was wondering the odds (if any) that one of these calculations is ...
1
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0answers
19 views
GLCD t6963c write data problem
I am trying to get a 128x240 LCD with t6963c driver. The pinout is ok and I could manage to make the cursor blink.
but it seems that no data is sent by write command ( write and increment = 0xC0 ) and ...
2
votes
1answer
103 views
Can I differentiate between a UPS, Generator and Main sine wave using a micro-controller?
Are there any distinguishing features of a mains power supply that will allow me to tell the difference between mains power supplied by
the utility company,
a generator, or
a UPS?
How can I use a ...
1
vote
2answers
90 views
Can I use one resistor divider to provide virtual ground to both halves of LM358 OpAmp?
I am trying to use an LM358 opamp to amplify an electret mic to something that I can read with my attiny85's ADC. (What can I say? I like DIP-8's :)
I feel that I need a gain of about 100 to get a ...
2
votes
1answer
40 views
t6963 GLCD very low contrast
I am trying to setup a 240x128 GLCD with t6963c driver (datasheet). I am familiar with ks0108 drivers but newbie in t6963.
I have written a simple code with only lcd-init() that I expect to see the ...
6
votes
1answer
76 views
What's mean these microcontroller pin input/output modes?
I bought an stm32f103ret6. When I saw the reference manual, I saw that it has several I/O modes.
For input: floating, pull-up, pull-down
For output: analog, open-drain, push-pull
I have already ...
0
votes
1answer
64 views
How does a 8 bit register bank hold 8 regsiters of 8 bits each?
In 8051, there are 128 bytes of RAM. Of which, 32 are set aside for registers in the form of banks, 8 registers to each bank. ...
2
votes
5answers
151 views
How can ADD be a 1 byte instruction?
I am learning 8051 coding. I came across the instructions of these forms ADD R7 and ADD A, R5. Now, since ...
1
vote
2answers
74 views
Why is pull-up resistor disabled in OUTPUT mode
I noticed in a lot of micro datasheets that the internal pull-up resistor is disabled automatically when the GPIO is in OUTPUT mode, but I'm not sure I understand why. Is a pull up resistor never ...
2
votes
1answer
108 views
Micro switch that closes circuit twice, on press and on release
I need to implement a switch that closes a circuit twice for a short time - when pressed and then when released. The switch needs to be really small (should fit inside a 3.5mm TRRS headphone jack, ...
5
votes
1answer
108 views
Why does the delay between bytes increase when I increase UART baud rate?
Something interesting to note, which I am not fully understanding. My UART is initialized with 9600 baud. I've looked at the TX on the line via logic analyzer, and the bytes I send have minimal delay. ...
1
vote
2answers
77 views
Audio optical cable electronic switch
Right now I'm using this to switch between three devices for my home stereo and I want to replace this with an electronic method (no moving parts) with a remote I made. I already have an rf module ...
