Spectrum ROM: Routine at 07813

07813: THE 'TWO-PARAM' SUBROUTINE

Used by the routines at OUT_CMD and POKE. The topmost parameter on the calculator stack must be compressible into a single register. It is two's complemented if it is negative. The second parameter must be compressible into a register pair.
TWO_PARAM	07813	CALL FP_TO_A	The parameter is fetched.
	07816	JR C,REPORT_B_2	Give an error if it is too high a number.
	07818	JR Z,TWO_P_1	Jump forward with positive numbers but two's complement negative numbers.
	07820	NEG
TWO_P_1	07822	PUSH AF	Save the first parameter whilst the second is fetched.
	07823	CALL FIND_INT2	Save the first parameter whilst the second is fetched.
	07826	POP AF	The first parameter is restored before returning.
	07827	RET	The first parameter is restored before returning.