Peer-to-peer, engineer-to-engineer questions and answers from the EDABoard.com engineering community around microcontrollers. Click the “Read more” link and follow the entire conversation and maybe add your two cents by logging in to EDAboard.com.

AC current measuring – I require to measure AC current by using a current transformer to a microcontroller. What techniques are there available? Read more

Two, 12-bit ADCs SPI coding  – My system needs data acquisition and processing and simultaneously displaying results on a 16×2 character LCD screen. I have an RF return loss measurement system. I have to display the return loss on LCD screen on the same PCB board. There are two 12-bit ADCs (ADS7042) and the MCU I have is ATmega128.

The equation to calculate return loss values in real time from the two ADCs codes is given as:

This equation has to be processed real-time for every different input, there will be two changed ADC codes and hence a different return loss value for every input. Read more

Reading uart using PIC18f – I am using pic18f97j60 with the c18 compiler and at 9600 baud rate. Currently, I want to read the response from uart which is a string.
I tried using functions given already however when my program reaches to either of those functions, everything freezes. Read more

GPS interfacing C code – Can anyone help me in getting this code right? Nothing is being printed out on the LCD screen. I made some corrects and debugged it so now there are no errors in debugging it. I attempted to send a char to the receiver in the AVR simulator IDE but nothing was printed on the LCD screen. Read more

Servo-control for generator start – I am designing a remote/auto start for 5kVA generator (gen) already fitted with 12V electric start. The gen is fitted with a choke lever which must be “played” progressively from fully closed while cranking, to fully open when full speed (3,000 RPM = 50Hz) is achieved. I have fitted a small RC-type servo (6Vdc / 50Hz / 180 degree = 1…2mS, etc). I have added a frequency counter to translate the motor speed which also works well displaying frequency. My problem is to USE the frequency output (Freq or FREQ) in order to control the servo satisfactorily instead of the pot. Read more

Flow meter code not working – My flow meter code is not working properly. I have to multiply the count of the TMR1 register by 2 to get the correct value. Why is it? Read more

Acquisition of a sinus signal – I have a problem with the acquisition of sinus signal.
I need the amplitude of two signals and am doing it with the PIC16f88. The problem is when I do the simulation with Proteus, I do not get anything on the LCD. Read more

STM32F4 Interfacing with a legacy chip – I have a problem getting the STM32F407 to talk with a legacy ASIC and I’ve been working very hard for the past two weeks trying to solve it. I will try to provide as many details as possible about the situation and my observations so far. Read more

Short C code for PIC16F627A builds but won’t run properly – Our short C code builds but won’t run properly. It is written in XC8 C in MPLAB. The microcontroller is PIC16F627A. Do you know why it doesn’t work as it should? Read more

Microcontroller as a web server in a local network – I have to store web pages (HTML) in controllers flash memory and read it with a browser. For that, please suggest a wifi module. Read more