Arithmetic on Multi-bytes Values

The carry bit (C), bit 0 of the status register, is set if an arithmetic operation overflows.

AVR instructions such as these allow the carry bit to be easily used for arithmetic on multi-byte values.
ADC Rd,Rr0001 11rd dddd rrrrRd = Rd + Rr + C
SBC Rd,Rr0000 10rd dddd rrrrRd = Rd - Rr - C

Index