Function:

Adds the packed BCD string at DS:SI to the packed BCD string at ES:DI. The
length of the string, in BCD digits, is specified in CL. Unlike Intel string
operations CL, DI & SI are unchanged by the operation. The Zero Flag (ZF) is
set if both operands are zero.  The Carry Flag (CF) and Overflow Flag (OF)
appear to be set by the addition of the most significant digits.

Note that 0F is treated as <POP CS> on the 88/86 and prefixes newer
instructions on 286+ CPUs.

(Supplied by Anthony Naggs)

See also SUB4S, CMP4S, ROL4, ROR4



BOUND  Checks register against limits
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