Spectrum ROM: Routine at 08329

The address of this routine is found in the parameter table.

This routine allows for values entered from the keyboard to be assigned to variables. It is also possible to have print items embedded in the INPUT statement and these items are printed in the lower part of the display.

The address of this routine is found in the parameter table. This routine allows for values entered from the keyboard to be assigned to variables. It is also possible to have print items embedded in the INPUT statement and these items are printed in the lower part of the display.
INPUT	08329	CALL SYNTAX_Z	Jump forward if syntax is being checked.
	08332	JR Z,INPUT_1	Jump forward if syntax is being checked.
	08334	LD A,1	Open channel 'K'.
	08336	CALL CHAN_OPEN	Open channel 'K'.
	08339	CALL CLS_LOWER	The lower part of the display is cleared.
INPUT_1	08342	LD (IY+2),1	Signal that the lower screen is being handled (set bit 0 of TV-FLAG and reset all other bits).
	08346	CALL IN_ITEM_1	Call the subroutine to deal with the INPUT items.
	08349	CALL CHECK_END	Move on to the next statement if checking syntax.
	08352	LD BC,(23688)	Fetch the current print position (S-POSN).
	08356	LD A,(23659)	Jump forward if the current position is above the lower screen (see DF-SZ).
	08359	CP B
	08360	JR C,INPUT_2
	08362	LD C,33	Otherwise set the print position to the top of the lower screen.
	08364	LD B,A
INPUT_2	08365	LD (23688),BC	Reset S-POSN.
	08369	LD A,25	Now set the scroll counter (SCR-CT).
	08371	SUB B
	08372	LD (23692),A
	08375	RES 0,(IY+2)	Signal 'main screen' (reset bit 0 of TV-FLAG).
	08379	CALL CL_SET	Set the system variables and exit via CLS_LOWER.
	08382	JP CLS_LOWER	Set the system variables and exit via CLS_LOWER.
The INPUT items and embedded PRINT items are dealt with in turn by the following loop.
IN_ITEM_1	08385	CALL PR_POSN_1	Consider first any position control characters.
	08388	JR Z,IN_ITEM_1	Consider first any position control characters.
	08390	CP "("	Jump forward if the present character is not a '('.
	08392	JR NZ,IN_ITEM_2	Jump forward if the present character is not a '('.
	08394	RST 32	Fetch the next character.
	08395	CALL PRINT_2	Now call the PRINT command routine to handle the items inside the brackets.
	08398	RST 24	Fetch the present character.
	08399	CP ")"	Give report C unless the character is a ')'.
	08401	JP NZ,REPORT_C	Give report C unless the character is a ')'.
	08404	RST 32	Fetch the next character and jump forward to see if there are any further INPUT items.
	08405	JP IN_NEXT_2
Now consider whether INPUT LINE is being used.
IN_ITEM_2	08408	CP 202	Jump forward if it is not 'LINE'.
	08410	JR NZ,IN_ITEM_3	Jump forward if it is not 'LINE'.
	08412	RST 32	Advance CH-ADD.
	08413	CALL CLASS_01	Determine the destination address for the variable.
	08416	SET 7,(IY+55)	Signal 'using INPUT LINE' (set bit 7 of FLAGX).
	08420	BIT 6,(IY+1)	Give report C unless using a string variable (bit 6 of FLAGS reset).
	08424	JP NZ,REPORT_C
	08427	JR IN_PROMPT	Jump forward to issue the prompt message.
Proceed to handle simple INPUT variables.
IN_ITEM_3	08429	CALL ALPHA	Jump to consider going round the loop again if the present character is not a letter.
	08432	JP NC,IN_NEXT_1
	08435	CALL CLASS_01	Determine the destination address for the variable.
	08438	RES 7,(IY+55)	Signal 'not INPUT LINE' (reset bit 7 of FLAGX).
The prompt message is now built up in the work space.
IN_PROMPT	08442	CALL SYNTAX_Z	Jump forward if only checking syntax.
	08445	JP Z,IN_NEXT_2	Jump forward if only checking syntax.
	08448	CALL SET_WORK	The work space is set to null.
	08451	LD HL,23665	This is FLAGX.
	08454	RES 6,(HL)	Signal 'string result'.
	08456	SET 5,(HL)	Signal 'INPUT mode'.
	08458	LD BC,1	Allow the prompt message only a single location.
	08461	BIT 7,(HL)	Jump forward if using 'LINE'.
	08463	JR NZ,IN_PR_2	Jump forward if using 'LINE'.
	08465	LD A,(23611)	Jump forward if awaiting a numeric entry (bit 6 of FLAGS set).
	08468	AND 64
	08470	JR NZ,IN_PR_1
	08472	LD C,3	A string entry will need three locations.
IN_PR_1	08474	OR (HL)	Bit 6 of FLAGX will become set for a numeric entry.
	08475	LD (HL),A	Bit 6 of FLAGX will become set for a numeric entry.
IN_PR_2	08476	RST 48	The required number of locations is made available.
	08477	LD (HL),13	A 'carriage return' goes into the last location.
	08479	LD A,C	Test bit 6 of the C register and jump forward if only one location was required.
	08480	RRCA
	08481	RRCA
	08482	JR NC,IN_PR_3
	08484	LD A,"\""	A 'double quotes' character goes into the first and second locations.
	08486	LD (DE),A
	08487	DEC HL
	08488	LD (HL),A
IN_PR_3	08489	LD (23643),HL	The position of the cursor (K-CUR) can now be saved.
In the case of INPUT LINE the EDITOR can be called without further preparation but for other types of INPUT the error stack has to be changed so as to trap errors.
	08492	BIT 7,(IY+55)	Jump forward with 'INPUT LINE' (bit 7 of FLAGX set).
	08496	JR NZ,IN_VAR_3	Jump forward with 'INPUT LINE' (bit 7 of FLAGX set).
	08498	LD HL,(23645)	Save the current values of CH-ADD and ERR-SP on the machine stack.
	08501	PUSH HL
	08502	LD HL,(23613)
	08505	PUSH HL
IN_VAR_1	08506	LD HL,8506	This will be the 'return point' in case of errors.
	08509	PUSH HL	This will be the 'return point' in case of errors.
	08510	BIT 4,(IY+48)	Only change the error stack pointer (ERR-SP) if using channel 'K' (bit 4 of FLAGS2 set).
	08514	JR Z,IN_VAR_2
	08516	LD (23613),SP
IN_VAR_2	08520	LD HL,(23649)	Set HL to the start of the INPUT line (WORKSP) and remove any floating-point forms. (There will not be any except perhaps after an error.)
	08523	CALL REMOVE_FP
	08526	LD (IY+0),255	Signal 'no error yet' by resetting ERR-NR.
	08530	CALL EDITOR	Now get the INPUT and with the syntax/run flag (bit 7 of FLAGS) indicating syntax, check the INPUT for errors; jump if in order; return to IN_VAR_1 if not.
	08533	RES 7,(IY+1)
	08537	CALL IN_ASSIGN
	08540	JR IN_VAR_4
IN_VAR_3	08542	CALL EDITOR	Get a 'LINE'.
All the system variables have to be reset before the actual assignment of a value can be made.
IN_VAR_4	08545	LD (IY+34),0	The cursor address (K-CUR) is reset.
	08549	CALL IN_CHAN_K	The jump is taken if using other than channel 'K'.
	08552	JR NZ,IN_VAR_5	The jump is taken if using other than channel 'K'.
	08554	CALL ED_COPY	The input-line is copied to the display and the position in ECHO-E made the current position in the lower screen.
	08557	LD BC,(23682)
	08561	CALL CL_SET
IN_VAR_5	08564	LD HL,23665	This is FLAGX.
	08567	RES 5,(HL)	Signal 'edit mode'.
	08569	BIT 7,(HL)	Jump forward if handling an INPUT LINE.
	08571	RES 7,(HL)
	08573	JR NZ,IN_VAR_6
	08575	POP HL	Drop the address IN-VAR-1.
	08576	POP HL	Reset the ERR-SP to its original address.
	08577	LD (23613),HL	Reset the ERR-SP to its original address.
	08580	POP HL	Save the original CH-ADD address in X-PTR.
	08581	LD (23647),HL	Save the original CH-ADD address in X-PTR.
	08584	SET 7,(IY+1)	Now with the syntax/run flag (bit 7 of FLAGS) indicating 'run' make the assignment.
	08588	CALL IN_ASSIGN
	08591	LD HL,(23647)	Restore the original address to CH-ADD and clear X-PTR.
	08594	LD (IY+38),0
	08598	LD (23645),HL
	08601	JR IN_NEXT_2	Jump forward to see if there are further INPUT items.
IN_VAR_6	08603	LD HL,(23651)	The length of the 'LINE' in the work space is found (STKBOT-WORKSP-1).
	08606	LD DE,(23649)
	08610	SCF
	08611	SBC HL,DE
	08613	LD B,H	DE points to the start and BC holds the length.
	08614	LD C,L	DE points to the start and BC holds the length.
	08615	CALL STK_STO	These parameters are stacked and the actual assignment made.
	08618	CALL LET
	08621	JR IN_NEXT_2	Also jump forward to consider further items.
Further items in the INPUT statement are considered.
IN_NEXT_1	08623	CALL PR_ITEM_1	Handle any print items.
IN_NEXT_2	08626	CALL PR_POSN_1	Handle any position controllers.
	08629	JP Z,IN_ITEM_1	Go around the loop again if there are further items; otherwise return.
	08632	RET