RI_EXEC/QA_OP and RI_EXECB/QA_MOP - Vectors $11C and $11E

These vectors execute one (RI_EXEC/QA_OP) or a list (RI_EXECB/QA_MOP) of arithmetic operations.

Call Parameters		Return Parameters
D0.W	Unused or operation	D0.L	Error code.
D7.L	Should be set to 0	D7.L	Preserved.
A1.L	Pointer to maths stack.	A1.L	Updated.
A3.L	Unused or pointer to list	A3.L	Preserved.
A4.L	Pointer to variables area	A4.L	Preserved.

ERR_OV	Overflow.

All registers not shown above are not used on entry and are preserved on exit.
D7 MUST be zero for qa_exp.
The detailed list of operations is given below. Unless otherwise stated, all operations are on floating point numbers on the maths stack.
The operations $00 to $32 are all performed on numbers on the stack. Operations $33 to $FF transfer 6 bytes (the length of a floating point number) between the maths stack and the variables area.
D0.W contains the single operation code for RI_EXEC/QA_OP and is unused for RI_EXECB/QA_MOP. Bits 8 to 15 of D0.W are not used and can take any value for operations $33 to $FF, but must be zero for the other operations.
Operations qa_n ($05) and qa_k ($07) cannot be used as a single operation.
(A1,A6.L) points to the maths stack.
For RI_EXECB/QA_MOP A3 points to a list of operations, each one byte long. The list is ended by a zero byte.
(A4,A6.L) points to the bottom of an area which can contain variables.

Operations

The odd operation codes less than $30 and code $32 are for SMSQ. These are similar to the codes used in Minerva.

Opcode	Name	Function	Change in A1
$00	-	End of ops	0
$01	qa_one	push 1	-6
$02	qa_nint	fp to nearest word integer	+4
$03	qa_zero	push 0	-6
$04	qa_int	truncate fp to word integer	+4
$05	qa_n	followed by a signed byte to push -128 to 127	-6
$06	qa_nlint	fp to nearest long word integer	+2
$07	qa_k	followed by a byte pushes a value (see table below)	-6
$08	qa_float	integer word to fp	-4
$09	qa_flong	integer long word to fp	-2
$0A	qa_add	add TOS to NOS	+6
$0C	qa_sub	subtract TOS from NOS	+6
$0D	qa_halve	TOS/2	0
$0E	qa_mul	TOS*NOS	+6
$0F	qa_doubl	TOS*2	0
$10	qa_div	NOS/TOS	+6
$11	qa_recip	1/TOS	0
$12	qa_abs	absolute value	0
$13	qa_roll	(TOS)B,C,A → (TOS)A,B,C (roll third to top)	0
$14	qa_neg	negate	0
$15	qa_over	NOS (A,B → B,A,B)	-6
$16	qa_dup	duplicate	-6
$17	qa_swap	TOS↔NOS	0
$18	qa_cos	cosine	0
$1A	qa_sin	sine	0
$1C	qa_tan	tangent	0
$1E	qa_cot	cotangent	0
$20	qa_asin	arcsine	0
$22	qa_acos	arccosine	0
$23	qa_atan2	arctangent(NOS/TOS)	+6
$24	qa_atan	arctangent	0
$26	qa_acot	arccotangent	0
$28	qa_sqrt	square root	0
$29	qa_squar	TOS*TOS	0
$2A	qa_log	natural logs	0
$2C	qa_l10	base 10 logs	0
$2E	qa_exp	exponential	0
$30	qa_pwrf	NOS raised to the power TOS	+6
$32	qa_pi	push pi	-6
$33	-	fp number from stack to -$CE(A4,A6.L)	+6
$34	-	fp number from -$CC(A4,A6.L) to stack	-6
$35	-	fp number from stack to -$CC(A4,A6.L)	+6
and so on until . .
$FC	-	fp number from -4(A4,A6.L) to stack	-6
$FD	-	fp number from stack to -4(A4,A6.L)	+6
$FE	-	fp number from -2(A4,A6.L) to stack	-6
$FF	-	fp number from stack to -2(A4,A6.L)	+6

qa_k Table

Byte	Name	Value
$56	qak_pi180	pi/180
$69	qak_loge	log₁₀e
$79	qak_pi6	pi/6
$88	qak_ln2	ln(2)
$98	qak_sqrt3	sqrt(3)
$A8	qak_pi	pi
$A7	qak_pi2	pi/2

This example shows how to use RI_EXECB/QA_MOP to calculate (x² - 1)/(x + 1). The answer is, of course, x - 1 but this gives a check on the operation. It is assumed that A6 points to the data space and that the variables area contains x as a floating point number. The op codes $FA and $FB push and pop the value at -6(A4,A6.L).

mt      equ     30              ; Space for A1 stack.
va      equ     mt+6            ; 6 bytes for variables area.

ops     dc.b    $FA             ; Push x           x
        dc.b    qa_squar        ; ($29) x*x        x*x
        dc.b    qa_one          ; ($01) push 1     1 : x*x
        dc.b    qa_sub          ; ($0C) NOS - TOS  x*x - 1
        dc.b    $FA             ; Push x           x : x*x - 1
        dc.b    qa_one          ; ($01) push 1     1 : x : x*x - 1
        dc.b    qa_add          ; ($0A) NOS + TOS  x + 1 : x*x - 1
        dc.b    qa_div          ; ($10) NOS/TOS    (x*x - 1)/(x + 1)
        dc.b    $FB             ; Pop answer
        dc.b    0               ; Mark end

calc    lea     mt,a1           ; Bottom of stack (relative to A6).
        lea     va,a4           ; Bottom of variables area (relative to A6).
        lea     ops,a3          ; Pointer to operations.
        movea.w RI_EXECB,a2     ; RI_EXECB vector address.
	jsr	(a2)		; Make the call
	bne.s	Error_handler	; Oops!

RI_EXEC/QA_OP and RI_EXECB/QA_MOP - Vectors $11C and $11E

Errors

Notes

Operations

qa_k Table

Example

QDOS Internals