Connecting 80 inputs to a microcontroller – I want to check inputs from optocouplers. How can I multiplex the inputs to a microcontroller? I prefer to use the8051, PIC16f877a, or ATMega. Read more.

MCP3428 interfacing – I am using the MCP3428 diferential ADC with a single shot conversion and interface through I2C to my microcontroller. It’s working fine but after 10 or 12 continuous hours, the IC is not giving any values. When I remove power and reconnect it starts working. Why is this happening and how can I solve this problem? Read more. 

Learning to program microcontrollers – I want to start programming microcontrollers and am thinking of starting with Microchip’s PICs or the ATMega. I can borrow a PIC DEM FS USB PIC18F4550 board but should I start with something else? What is your advice to someone starting on microcontrollers? Read more.

Choosing a suitable PIC microcontroller for a solar charger – I’m planning to build a PWM solar charger for home use with flexibility and scalability in mind. I expect to incorporate the solar charger with the following features:

1. Based on PWM algorithm
2. Charging multiple 12V sealed lead acid batteries
3. 20×4 character LCD display for displaying voltages,current,power etc
4. Over voltage / Under voltage / Lightning protection
5. Reverse power flow protection
6. Short Circuit and Over load protection

After much research, I have decided to go with Microchip’s XLP  microcontrollers. These are the options I have but I need to know if these chips adequate or are better options available? Read more. 

Why is the SPI LCD not working? – I am using a Microchip 8-bit SPI Port expander. The SPI debugger shows that data is being sent properly. I am testing it in both Proteus and hardware and it is not working in either. I am using a Slaeae logic analyzer for testing in hardware and a EasyPIC v7 development board. Below is my PRO PIC project and Proteus file. Read more.