Question

The AVR provides a rich instruction set to support high-level languages. The AVR address- ing modes also simplify the access of complex data structures. The AVR has a version of the ADD instruction that includes the C flag as one of the source operands, which enables multiple- precision addition operation. The AVR also has a version of the SUB instruction that includes the C flag as one of source operands and hence is used to perform multiprecision subtraction operation. The arithmetic and logical operations can only be performed on operands in registers. Memory operands must be loaded into a register before these operations can be performed 2.9 Exercises E2.1 Write an instruction sequence to swap the contents of registers rO and rl. A third register such as r2 or another can be used to facilitate the swap operation. E2.2 Write an instruction sequence to swap the contents of data memory locations at 0x2000 and 0x2001 E2.3 Write an instruction sequence to copy three bytes from data memory location at 0x1000-0x1002 to data memory locations at 0x2000-0x2002, respectively E2.4 Write an instruction sequence to store I, 3, and 5 at data memory locations at 0x2000, 0x2005, and 0x200A, respectively E25 Write a sequence of instructions to add S to data memory locations at 0x2000, 0x2001, and 0x2002, respectively E2.6 Write a sequence of instructions to suberact 10 from data memory locations at 0x2000, Ox2005, and Ox200A, respectively E2.7 Write a sequence of instructions to add the three numbers stored in data memory loca tions at 0x2000, 0x2001, and 0x2002 and store the sum at data memory location at 0rx2010o. E2s Write an instruction sequence to add 35 to the two-byte value stored at data memory loca tions 0x200010x2001 E2.9 Write an instruction sequence to ourput the value 0xAA to PORTC E2.10 Write a sequence of instructions to copy the three bytes from program memory locations 0x2000-0x2002 to data memory locations at Ox2000-0x2002, respectively E2.11 Write an instruction at 0x1000 and 0x1005 together and leave the sum in the data memory location at 0x2000 E2.12 Write an instruction sequence to swap the 16-bit value stored in data memory location at 0x2000-0x2001 with the 16-bit value stored in the data memory at 0x2020-0x2021. E213 Write an instruction sequence to subtract the value stored at data memory location sequence to add the two s-bit numbers stored in program memory Ox2000 from the sum of the values stored at data memory locations ox2010 and oxzoll and leave the difference in ro. E2.14 Write an instruction sequence to subtract the sum of data memoty locations at 0x2000 and 0x2001 from the sum of the data memory locations ar Ox2010 and 0x2011 and leave the difference at data memory location 0x2020 Write an instruction sequence to add the 16-bit value stored at data memory locations 0x2000-0x2001 and the 16-bit value stored at program memory locations Ox2010-0x2011 and store the sum at data memory locations 0x2020-0x2021