LD pd,ps+HL     Load     Rabbit 4000 Instruction

Opcode	Instruction	Clocks	Operation
--	LD pd,ps+HL	4 (2,2)	pd = ps + HL
6D 0E	LD PW,PW+HL	4 (2,2)	PW = PW + HL
6D 1E	LD PW,PX+HL		PW = PX + HL
6D 2E	LD PW,PY+HL		PW = PY + HL
6D 3E	LD PW,PZ+HL		PW = PZ + HL
6D 4E	LD PX,PW+HL	4 (2,2)	PX = PW + HL
6D 5E	LD PX,PX+HL		PX = PX + HL
6D 6E	LD PX,PY+HL		PX = PY + HL
6D 7E	LD PX,PZ+HL		PX = PZ + HL
6D 8E	LD PY,PW+HL	4 (2,2)	PY = PW + HL
6D 9E	LD PY,PX+HL		PY = PX + HL
6D AE	LD PY,PY+HL		PY = PY + HL
6D BE	LD PY,PZ+HL		PY = PZ + HL
6D CE	LD PZ,PW+HL	4 (2,2)	PZ = PW + HL
6D DE	LD PZ,PX+HL		PZ = PX + HL
6D EE	LD PZ,PY+HL		PZ = PY + HL
6D FE	LD PZ,PZ+HL		PZ = PZ + HL

Flags				ALTD			IOI/IOE
S	Z	L/V	C	F	R	SP	S	D
-	-	-	-		·

Description

Loads pd (any of the 32-bit registers PW, PX, PY or PZ) with the sum of ps (any of PW, PX, PY or PZ) and HL. These instructions cannot be used for general 32-bit arithmetic because the addition depends on the upper two bytes of ps. If the upper two bytes are all ones, then it is 16-bit addition. The following example illustrates this point:

ld PW,0xFFFFFFFF
ld PW,PW+HL            ;yields PW=0xFFFF0000 if HL=1

ld PW,0x7FFFFFFF
ld PW,PW+HL            ;yields PW=0x80000000 if HL=1