Commit: d061fffd61d9e27f8c9f3d459a1e6e1a3871daef - nsvtl (git)

Deriving a new dialect of Very Tiny Language from VTL-2 6800 version

Commit MetaInfo

• Revision: d061fffd61d9e27f8c9f3d459a1e6e1a3871daef (tree)
• Time: 2022-09-25 21:45:57
• Author: Joel Matthew Rees <joel.rees@gmai...>
• Commiter: Joel Matthew Rees

Log Message

Moved DP to avoid conflicts (this is the one that had functional expressions)

Change Summary

• modified: VTL_6809_coco_translit.asm

Incremental Difference

--- a/VTL_6809_coco_translit.asm
+++ b/VTL_6809_coco_translit.asm
@@ -33,7 +33,9 @@ BREAK	EQU	$03
 *ACIACS	EQU	$FCF4	; exorcisor
 *ACIADA	EQU	$FCF5	; exorcisor
 *
-*	A few interpreter variables in the direct page won't hurt.
+*	A few interpreter variables in the direct page won't hurt, said the snake oil vendor.
+*	(See SNDDUR and PLYTMR in particular.)
+*	(Really need to move these. Use DP after all? IRQ, at least, uses extended mode addressing.)
 *	(Yes, I can hear voices of complaint that it's not as "tight" as it could be.)
 *	(This allows us to save more ROM space and uses DP that would otherwise go wasted.)
 *	(Trade-offs.)
@@ -47,7 +49,7 @@ BREAK	EQU	$03
 *	Does not really make specific use of the DP register.
 * 	ORG	$C0	; Move this according to your environment's needs.
 * Change this to move the registers:
-DPBASE	EQU	$D0	; PIA mask at $C2? Avoid it, anyway.
+DPBASE	EQU	$C4	; PIA mask at $C2? Avoid it, anyway.
 * PARSET	RMB	2	; Instead of SAVE0 in TERM/NXTRM
 PARSET	EQU	DPBASE+2
 * CVTSUM	RMB	2	; Instead of SAVE1 in CBLOOP
@@ -79,6 +81,9 @@ DST	EQU	SRC+2
 STKMRK	EQU	DST+2	; to restore the stack on each pass.
 DPALLOC	EQU	STKMRK+2	; total storage declared in the direct page
 *
+*******!!!!!! Check that we have avoided $00E2, as well, since it is used as PLYTMR by an interrupt routine.
+*             Also, $008D is used as SNDDUR by BASIC.
+*
 *	SET ASIDE FOUR BYTES FOR USER
 *	DEFINED INTERUPT ROUTINE IF NEEDED
 ZERO	EQU	$1600	; Dodge BASIC and video use RAM.
@@ -180,35 +185,42 @@ PROBE	STA	0,X
 	CMPB	0,X
 	BNE	NOTRAM		; all bits seem to be R/W.
 	LEAX	1,X
-	STX	$400	; DBG
 PROBET	CMPX	#COLD
 	BLO	PROBE	; CMPX on 6809 works right.
 NOTRAM	LEAX	-1,X
 	STX	STAR
-	STX	$402	; DBG
+*	STX	$402	; DBG
 START
+	STX	$400	; DBG
 *	LDS	#STACK	; re-initialize at beginning of each evaluate
 	LDS	STKMRK	; from mark instead of constant
 	STS	SEMI	; DBG Comment this out when we no longer need to see the stack pointer BASIC gives us.
 	CLRA		; NUL delimiter
 	LDX	#OKM
-	STX	$404	; DBG
+*	STX	$404	; DBG
 	LBSR	STRING
-	BRA	*	; DBG
+*	BRA	*	; DBG
 *
 LOOP	CLRA
 	STA	DOLR
 	STA	DOLR+1
-	JSR	CVTLN
+	INC	$40D	; DBG
+	STA	$420	; DBG
+	LBSR	CVTLN
+	INC	$40E	; DBG
+	STA	$421	; DBG
 	BCC	STMNT	; NO LINE# THEN EXEC
 	BSR	EXEC
 	BEQ	START
 *
 LOOP2	BSR	FIND	; FIND LINE
 EQSTRT	BEQ	START	; IF END THEN STOP
+	DEC	$42A	; DBG
 	LDX	0,X	; LOAD REAL LINE #
+	STX	$42B	; DBG
 	STX	DOLR	; SAVE IT
 	LDX	SAVLIN	; GET LINE
+	STX	$42D	; DBG
 	LEAX	3,X	; BUMP PAST LINE # and SPACE
 	BSR	EXEC	; EXECUTE IT
 	BEQ	LOOP3	; IF ZERO, CONTINUE
@@ -264,23 +276,29 @@ LOOKAG	LEAX	1,X	; FIND END OF LINE
 	RTS
 *
 FIND	LDX	#PRGM	; FIND LINE
+	DEC	$425	; DBG
 FND2	STX	SAVLIN
 	CMPX	AMPR
 	BEQ	RTS1
+	DEC	$426	; DBG
 *	LDA	1,X	; almost missed this.
 *	SUBA	DOLR+1	; This was necessary because no SUBD
 *	LDA	0,X	; and CPX does not affect C flag on 6800
 *	SBCA	DOLR
-*	PSHB		; B does not seem to be in use.
+*	PSHS	B		; B does not seem to be in use.
 	LDD	0,X	; Use D because we think we want to keep X.
 	SUBD	DOLR
-*	PULB
+*	PULS	B
 	BCC	SET
+	DEC	$427	; DBG
 FND3	BSR	NXTXT
+	DEC	$428	; DBG
 	BRA	FND2
 *
 SET	LDA	#$FF	; SET NOT EQUAL
-RTS1	RTS
+RTS1
+	CLR	$429	; DBG (Z FLAG SET)
+	RTS
 *
 EVALU	LBSR	EVAL	; EVALUATE LINE
 	PSHS	A,B	; A is pushed after B
@@ -307,8 +325,11 @@ AR2RND	ADDB	QUITE	; RANDOMIZER	; Adding the low byte to the high byte
 	STD	QUITE
 	RTS
 *
-SKP2	BSR	FIND	; FIND LINE
+SKP2
+	DEC	$422	; DBG
+	BSR	FIND	; FIND LINE
 	BEQ	INSRT	; IF NOT THERE
+	DEC	$423	; DBG
 	LDX	0,X	; THEN INSERT
 	CMPX	DOLR	; NEW LINE
 	BNE	INSRT
@@ -337,7 +358,10 @@ DELT	LDX	SRC
 FITIT	LDX	DST
 	STX	AMPR	; STORE NEW END
 *
-INSRT	LDX	EDTLIN	; COUNT NEW LINE LENGTH
+INSRT
+	INC	$423	; DBG
+	LDX	EDTLIN	; COUNT NEW LINE LENGTH
+	STX	$430	; DBG
 	LDB	#$03
 	TST	0,X
 	BEQ	GOTIT	; IF NO LINE THEN STOP
@@ -345,19 +369,21 @@ CNTLN	INCB		; count bytes
 	LEAX	1,X
 	TST	0,X	; Find trailing NUL
 	BNE	CNTLN
+	STX	$432	; DBG
+	STB	$434	; DBG
 *
 OPEN	CLRA		; CALCULATE NEW END
 	ADDD	AMPR
 	STD	INSPTR
+	STD	$437	; DBG
 	SUBD	STAR
 	LBCC	START	; IF TOO BIG THEN STOP
 	LDX	AMPR
-*	LDS	INSPTR	; remember that the 6800/6801 stack is postdecrement push.
+	STX	$435
+*	LDS	INSPTR	; Remember that the 6800/6801 stack is postdecrement push.
 *	STS	AMPR
-	LDD	INSPTR	; remember that the 6800/6801 stack is postdecrement push.
+	LDD	INSPTR	; The 6809 stack is predecrement push, but that doesn't matter here.
 	STD	AMPR
-*
-*	LDS	AMPR
 	STD	DST
 	LEAX	1,X	; SLIDE OPEN GAP
 SLIDE	LEAX	-1,X	; going down
@@ -374,13 +400,16 @@ SLIDE	LEAX	-1,X	; going down
 *
 * DON	LDS	DOLR	; STORE LINE #
 *	STS	0,X
-DON	LDD	DOLR	; STORE LINE #
-	STD	0,X
-	STX	DST	; will skip by offset store
+DON
+	STX	$439	; DBG
+	LDD	DOLR	; STORE LINE #
+	STD	0,X	; Note MSB1st byte order implicit dependency here.
+	STX	DST	; will skip by offset on store
 *	LDS	EDTLIN	; GET NEW LINE
 *	DES		; pre-increment
 	LDD	EDTLIN	; GET NEW LINE
 	STD	SRC
+	STD	$43B	; DBG
 *
 *MOVL	INX		; INSERT NEW LINE (skip over LINE # hi byte)
 *	PULB
@@ -396,7 +425,10 @@ MOVL	LDX	SRC
 *
 GOTIT
 *	LDS	#STACK	; Ready for a new line of input.
+	STS	$41C	; DBG
 	LDS	STKMRK	; restore from mark
+	STS	$41E	; DBG
+	STX	$43D	; DBG
 	LBRA	LOOP
 *
 * RSTRT	LBRA	START	; warm start over
@@ -433,27 +465,27 @@ ZRSUP	LEAX	1,X
 *
 PNTMSG	CLRA		; ZERO FOR DELIM
 STRTMS	STA	DELIM	; STORE DELIMTER
-	DEC	$408	; DBG
+*	DEC	$408	; DBG
 *
 OUTMSG	LDB	,X+	; GENERAL PURPOSE PRINT
-	INC	$409	; DBG
-	STB	$40A	; DBG
+*	INC	$409	; DBG
+*	STB	$40A	; DBG
 	CMPB	DELIM
 	BEQ	CTLC
 	LBSR	OUTCH
-	STB	$40C	; DBG
+*	STB	$40C	; DBG
 	BRA	OUTMSG
 *
 CTLC
-	INC	$420	; DBG
+*	INC	$420	; DBG
 	LBSR	POLCAT	; POL FOR CHARACTER
-	INC	$421	; DBG
+*	INC	$421	; DBG
 	BCC	RTS2	; return wherever we came from
-	INC	$422	; DBG
-	STB	$423	; DBG
+*	INC	$422	; DBG
+*	STB	$423	; DBG
 	LBSR	INCH
 	CMPB	#BREAK	; BREAK KEY?
-	STB	$424	; DBG
+*	STB	$424	; DBG
 	LBEQ	START
 *
 INCH2	LBRA	INCH
@@ -747,7 +779,7 @@ INCH	BSR	POLCAT
 *
 *	OUTPUT ONE CHAR 
 OUTCH	PSHS	B,A
-	TFR	A,B
+	TFR	B,A
 	JSR	[OUTCHV]
 *	INC	$410	; DBG
 *	STA	&411	; DBG