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Using a PIC to generate square wave sweep tones – I am trying to design a controller for a 12V siren (for an alarm system). The controller will output square waves from the PIC using 2 outputs that are 180-deg out of phase with each other (inverted). Both outputs feed through an H-BRIDGE amp to an 8Ω speaker (to get maximum volume). I do NOT need sine waves, sawtooth, etc. I only need to output square waves. Frequency range will be as low as 300Hz to as high as 2650Hz. Read more

MikroC project check – I’ve made a simple controller for a 3-stage elevator. The main problem is that when testing on Proteus it works great and even on a real board. But sometimes there are errors such as not responding to the emergency push button (which its normally closed) or converting the input pins to outputs and not responding to the limit switch. Read more

P10 led connection explanation – I have interfaced my own LED matrix with PIC, 8051,  and AVR microncontrollers. Now I want to interface it with a P10 LED module. The pins are shown here. Need help programming. Read more

PIC18f4520 serial communication problem – I wrote a code for serial communication using PIC18F4520 and Mikroc pro. I tested it using USART terminal provided with Mikro. It is working fine. Then I tested it on another laptop with the same USART terminal. It worked fine. Both these laptop are Windows 7 32-bit systems. Then I tested it on Windows 8 with the same USART terminal software. Here it failed to work. I then tested it with another hyperterminal software on the same laptop but it didn’t work. Why? Read more

Interfacing P10 LED matrix module – I am trying to interface the P10 LED matrix display module with PIC16f1939 running at 32MHz, MPLABx and HI TECH C Compiler. To send the data to the display, I am using a software SPI routine. However I don’t see anything on my display; it’s just blank. Read more

Problem with call function in MikroC – I am using an Atmega8A, a 16 M crystal, and a MikroC for AVR IDE. I have a function I want to call about 150 times continuously. But my code does not work. If I call it less than 30 times, it will work. Why? Read more

Is PIC16F505 a good choice? – I want to use a microcontroller for my design for checking input and output current and voltages, triggering FETs, and battery charge monitoring. I have chosen the PIC16F505. Will this be a good choice for my application? Read more

Need help with PIC16F877A using Pickit3 – I’m trying to connect a PIC16F877A to program it in MPLAB X IDE, but I’m getting an error about the target device ID. Below is my breadboard. Read more

Illegal conversion between types – I am trying to reuse a code for different pins in the PIC16f877a. For that, I have uses the structure concept in C. I haven’t completed my program. I compiled it for any syntax errors and I got this error: [illegal conversion between types int -> struct DHT11]. Read more

PIC microcontroller port pins changing – I want to interface both SPI and I2C devices in the same PIC microcontroller. How can I  change the pins of the I2C? Read more