Knowledge Base

X = Y + X + ((R:23) ? 1 : 0); R:23 = <carry>; (Y = T; Z = T)

Simple binary 8-bit add of X and Y, with carry in taken from bit 0 or R. Pops the operands off the stack, leaves the result in X. If the addition produces a carry sets R = 1.

The R register does double duty as result flags for binary arithmetic instructions.

From dialect 23 bit 0 of R is the carry flag. A carry out of an ADD, ADC, SUB or SBC instruction will set bit 0 of R.

The same bit 0 the acts as the carry input to ADC and SBC.

See also ADD, SUB, SBC, RtoX