I have this $2 (or less, converted from PHP 100) analog TV box that I opened (because I love opening things and hate putting it back) which happened to have an ATMEL AT89C51 microcontroller. Beside the microcontroller there's this Serial EEPROM (atmel712 24c028). Can I use it? Not necessarily use the arduino bootloader. How will I reprogram it? What extra tools will I need (hardware or software)? It also has a tuner that the microcontroller controls and that tuner can transmit and receive.

Block Diagram. PORT 2 DRIVERS. Under operating conditions, load capacitance for Port 0, ALE/PROG, and PSEN = 100 pF; load capacitance for all other outputs = 80 pF.

And I guess I have something in mind to do with these. Where will I start?

AVR (8 bit) - Made by Atmel. Uses AVR instruction set.

PIC (8 bit) - Made by Microchip. Uses PIC instruction set. 8051 (only 8 bit) - Made by everyone and their uncle. Uses 8051 instruction set, originally by Intel who gave up selling these 15 years ago when they decided anything that didn't net them $50 wasn't worth their time. So we are talking about three different and totally incompatible 8-bit architectures. Like 6052, Z-80, and 6800. But it doesn't matter so much if you have a C compiler to do the dirty work for you.

There is always a way to interface digital ICs, even if they are running at different voltage levels. But if they are all running at the same voltage, say +5V/0V, it's pretty simple.

Logic pin to logic pin connections are just a wire or a trace - no resistors or anything else needed unless you are trying to communicate in multi-megahertz speeds. (you may need a pullup resistor if the output is open-drain, but this is not likely). The only trouble you might have is making your software synchronize things well - that is to make sure the receiving MCU is ready when the transmitting one is transmitting. This can be done with either interrupts or polling. Gpg Full Installer Pro.