Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [8051]

The "8051" is a (still) very popular chip in the Intel MCS-51 micro controller series.

See also

281 questions
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4 answers

Can individual pins of different port of a microcontroller be mapped to a register and their values be changed when changing the register value?

Q: Can individual pins of different port of a micro-controller be mapped to a register and their values be changed when changing the register value? Scenario: I have used up some pins from each port(8-bits) of the micro-controller. Now I want to…
Osaid
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4 answers

Open-drain microcontoller ports

I want to understand the concept of open-drain ports like port P0 of the 8051 microcontroller. Why do we need to connect pull up resistors to the port P0? I have basic knowledge of MOSFETs and other electronic devices.
abkds
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Why this code wasn't written in a much simpler way?

I have came across a question while working on assembly language. Here is the question: Assume that bit P2.2 is used to control an outdoor light and bit P2.5 a light inside a building. Show how to turn on the outside light and turn off the inside…
İlker Demirel
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What is a good way to in-circuit update the program on a SyncMOS 5964?

I want something that can re-program a PQFP SyncMOS SM5964 chip already soldered to the target circuit board. I picture a ribbon cable that I plug between some sort of 2x8 or so header connector soldered on the target circuit board, and a 2x8 or so…
davidcary
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Beginner 8051 microcontroller kit recommendation?

I'm reposting this from stackoverflow, as the question is better suited here. I'm a first year Computer Science student looking to get started with development for micro-controllers. I'd like to use the 8051, as it's common as dirt, and is used…
LucidDefender
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1 answer

Texas Instruments Compiler

I am working with TI's CC2533 SoC Low Power RF I bought a few chips and assembled a few PCBs.. Using TI's debugger I confirmed that I can send and receive packets using the basic RF using the RFStudio. Something I have not realised is that TI does…
Piotr Kula
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Project ideas for five hundred AT89C52s?

I happen to have some 500 old AT89C52 controllers and am looking for ideas how to use them in a project. That's an 8051-based controller with 8K Flash, so you get an idea. And no, trashing them is not a project! :-) I remember that in the 80s Steve…
stevenvh
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The crystal oscillator used in UART is of 11.059MHZ, why?

I want know UART crystal used in it why it is of 11.05MHZ, and why we use it.
Mamta Varma
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ADuC812 needs DAC value written twice. Is that normal/common?

A while ago I had a project that involved Analog Devices ADuC812 microconverter. Amongst assorted on-board hardware, the device had two very helpful DAC converters, that could source 0-5V on their respective pins and even maintain a respectable…
SF.
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How to use nRF24LE1 with Arduino and nRF24L01+

I know nRF24LE1 has 8051 core and is compatible RF protocol with nRF24L01+. But are the nordic libraries compatible with Arduino libraries. Does anyone has used both these devices, please help me in finding compatible libraries. I want to connect…
Priyank Bolia
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1 answer

Weird current at 8051 port 1 pin

The pins in Port 1 has internal pull-ups when used for input. The Mosfet is off and the drain is pulled high using an internal pull-up resister. I connect an ammeter and see that the current (IL current) flowing to ground is about 15uA. I inferred…
Arjob Mukherjee
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8051 serial debug monitors

I'm working with an 8051 (Cypress FX2LP) that doesn't have jtag/bdm capability. Typically, developers on this project have been using ad-hoc serial printfs for debugging. I'm looking into options for serial debug monitors such as Keil's Mon51, Isd51…
JimFred
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What is with the popularity of the 8051 Core?

I keep seeing the old 8051 architecture around a lot. But I can't see why people would want to use this old architecture in their products when there seem better alternatives around, such as ARM cores, and if you're not designing your own MSP430s,…
Dean
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Is an ADC always necessary between 8051 and zero crossing detector?

I am making a SCR(Thyristor) trigger by using 8051 microcontroller. I have a here is a zero cross detecting (ZCD) circuit which detects the zero points and this is conveyed to the 8051 which will do further action. The ZCD circuit is made up of BJT…
Santosh
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Hardware and software to program AT89S52 chips with linux

Seeing that the ATMEL AT89S52 chips are so cheap (8 usd for 5 with free shipping from ebay!), are supposed to have a simple architecture and a lot of documentation available online, I would like to use them to learn microcontrollers at a lower level…
nib0
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