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  1. V

    Can someone please explain the "readKey" subroutine in this code

    I haven't learnt the coding part of keypad integration in 8051 yet, but I'm aware of the working and theory behind the integration. I'd really appreciate it if someone explains the readKey subroutine in the attached file. Thanks in advance. - Kat
  2. V

    How do I get two digit inputs using ASM for my Calculator using 8051?

    I chose to make a Calculator for my "Microcotrollers and Its Applications" course's Project component. I'm not really good at ASM progrmming, I'm more of a C guy (I'm not really good at programming microcontrollers though), but my faculty said the projects MUST be coded in ASM language. So I...
  3. M

    8051 program not processing keypad matrix correctly

    I made myself a small PCB (measuring about 6cm by 5cm). This is what is supposed to happen: 1. Upon power-up, the LED goes red to indicate that the unit is ready for input. 2. I then press any key down (where the contacts in the button meet), then the red led goes off. 3. The correct value is...
  4. M

    Key tied to two GPIO pins not functioning correctly

    I'm posting this here because it may be more of an electronics issue. Anyways, I have a program which calls the dkey function to try to get a value based on the key pressed. I have three keys. Two are tied to their own GPIO pins and the third key functions exactly the same as the other two...
  5. V

    IR based Speed control of Single Phase AC motor using a Microcontroller 8051

    Hi all, My project is to create an infrared remote to change the speed and switch on/off of a cap start/run type single phase induction motor operating at AC mains (230V, 50Hz). I have worked out the controlling the speed of the motor part (using a solid state relay to control phase angle of...
  6. S

    ATMEL89S8253, assembler

    Hello, I need to write a program in assembler for a microcontroller ATMEL89S8253 as a college job. The microcontroller is connected to a DOS computer with rs232. The program is supposed to rely on autorepets, after pressing the button is to send many characters, but no more than 2 per second. I...
  7. D

    Cannot clear flag 'IE3' on 8051 microcontroller

    I am just learning to program in assembly using the 8051 microcontroller, and I am working on a simple Jeopardy-style project in which I have two clickers and a reset button, and one of two LED lights turns on depending upon which clicker is clicked first. I am writing the program for this...
  8. 2

    Program in assembly language for 8051 microcontroller that can perform floating point calculation

    Hello, How I can make a program in assembly language for the 8051 microcontroller that can perform floating point calculations?. Excuse my English, I 'm Hispanic and I found this excellent forum and want to see if any of you could help me with this problem. I need a way to perform calculations...
  9. C

    Fire Alarm Code Help

    Need help with the following Homework assignment… Design a fire alarm system using a 8051 microcontroller. The specs are as follows: A) If the alarm is detected (one of the switches is activated) it should start flashing 4 LEDS (4 on the right (LEDS 1-4) and 4 on the left (LEDS 5-8)...
  10. Greital

    help with :::Generate a random number using interrupt:::

    hi still working on my 8051 project using assembly language, and now I'm in phase 4 --->>>> the last phase ;) in this phase we should generate 2 random numbers as following: 1. one digit (1-9) 2. two digit (10-99) and by using push button we pick randomly the number we have done one digit...
  11. Greital

    help with converting numbers to letters in 8051 assembly

    hi, I'm trying to complete my project in assembly 8051 , and thanks to all of you I completed the 1st phase now I'm stuck in the 2nd phase I should convert a number to its letters --->> for example if I put R3 = #31 it should print thirty one I know I had to make an arrays: 1. single digit...
  12. Greital

    Maximum delay can be implemented by timers

    hi, I'm kinda new to 8051 and have a problems with it :( Q: assuming 8051 is connected to a 6Mhz crystal, what is the maximum delay that can be implemented by a single timer using mode 1 ? what I've tried is the following: 1. finding the freq = 6/12 Mhz 2. finding the cycle of time =...

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