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Where are the registers located?
Register memory is the smallest and fastest memory in a computer. It is not a part of the main memory and is located in the CPU in the form of registers, which are the smallest data holding elements. A register temporarily holds frequently used data, instructions, and memory address that are to be used by CPU.
How many general purpose registers are present in AVR?
32 general-purpose
There are 32 general-purpose 8-bit registers, R0–R31. All arithmetic and logic operations operate on those registers; only load and store instructions access RAM.
What is AVR register?
All information in the microcontroller, from the program memory, the timer information, to the state on any of input or output pins, is stored in registers. Registers are like shelves in the bookshelf of processor memory.
How many GPRS are there in the AVR microcontroller?
Then AVR-GSM is the board for you! It contains ATmega32 microcontroller and 3-band GSM GPRS module 900/1800/1900Mhz inside which covers most used GSM networks around the world.
How do I directly access a memory mapped register of AVR?
The reason the AVR headers define the IO port registers this way is because in addition to the standard load/store instructions that can access the entire data memory address space and take three clock cycles to complete, the IO registers are special, and can also be accessed using IN/OUT instructions, which complete in two cycles.
What is the 1 Register in AVR used for?
This register is used to configure the PORT pins as Input or Output. Writing 1’s to DDRx will make the corresponding PORTx pins as output. Similarly writing 0’s to DDRx will make the corresponding PORTx pins as Input.
What does DDRB mean in AVR I / O register?
DDRB = 0xff; // Configure PORTB as Output. DDRC = 0x00; // Configure PORTC as Input. This register is used to send the data to port pins. Writing 1’s to PORTx will make the corresponding PORTx pins as HIGH.
How to write 0’S to ports in AVR?
Similarly writing 0’s to PORTx will make the corresponding PORTx pins as LOW. PORTB = 0xff; // Make all PORTB pins HIGH. PORTC = 0x00; // Make all PORTC pins LOW.. This register is used to read the data from the port pins. Before reading the data from the port pins, the ports needs to be configured as Inputs.