From e9f854c06ad3972eeb23006f5aa64b58c4686976 Mon Sep 17 00:00:00 2001
From: David Schmenk <dschmenk@gmail.com>
Date: Sat, 24 May 2014 14:18:43 -0700
Subject: [PATCH] Save startup path for relaunching CMD after SYS program

---
 PLASMA/src/plvm02.s | 56 ++++++++++++++++++++++++++++++++++-----------
 1 file changed, 43 insertions(+), 13 deletions(-)

diff --git a/PLASMA/src/plvm02.s b/PLASMA/src/plvm02.s
index 44876bd7..57035ecb 100644
--- a/PLASMA/src/plvm02.s
+++ b/PLASMA/src/plvm02.s
@@ -37,6 +37,7 @@ ALTRDON	=	$C003
 ALTWROFF=	$C004
 ALTWRON	=	$C005
 	!SOURCE	"plvm02zp.inc"
+STRBUF	=	$0280
 ;**********************************************************
 ;*
 ;* INTERPRETER INSTRUCTION POINTER INCREMENT MACRO
@@ -131,6 +132,35 @@ RAMDONE	CLI
 	INY
 	BNE	-
 ;*
+;* SAVE DEFAULT COMMAND INTERPRETER PATH IN LC
+;*
+	JSR     PRODOS          ; GET PREFIX
+	!BYTE	$C7
+	!WORD	GETPFXPARMS
+	LDY	STRBUF		; APPEND "CMD"
+	LDA	#"/"
+	CMP	STRBUF,Y
+	BEQ	+
+	INY
+	STA	STRBUF,Y
++	LDA	#"C"
+	INY
+	STA	STRBUF,Y
+	LDA	#"M"
+	INY
+	STA	STRBUF,Y
+	LDA	#"D"
+	INY
+	STA	STRBUF,Y
+	STY	STRBUF
+	BIT	LCRWEN+LCBNK2	; COPY TO LC FOR BYE
+	BIT	LCRWEN+LCBNK2
+-	LDA	STRBUF,Y
+	STA	$D103,Y		; YEAH, I HARDCODED THE ADDRESS
+	DEY
+	BPL	-
+	
+;*
 ;* LOOK FOR STARTUP FILE
 ;*
 	JSR     PRODOS          ; OPEN AUTORUN
@@ -150,12 +180,13 @@ RAMDONE	CLI
 	!WORD	READPARMS
 	BNE     NOAUTO
 	LDX     READPARMS+6
-	STX     $0280
+	STX     STRBUF		; STRING LENGTH
 	JSR     PRODOS
 	!BYTE	$CC
 	!WORD	CLOSEPARMS
-	JMP     CMDEXEC
-NOAUTO	JMP	BYE		; LOAD DEFAULT
+NOAUTO	JMP     CMDEXEC
+GETPFXPARMS !BYTE 1
+	!WORD	STRBUF		; PATH STRING GOES HERE
 AUTORUN !BYTE	7
 	!TEXT	"AUTORUN"
 OPENPARMS !BYTE	3
@@ -168,7 +199,7 @@ NLPARMS	!BYTE	3
 	!BYTE	$0D
 READPARMS !BYTE	4
 	!BYTE	0
-	!WORD	$0281
+	!WORD	STRBUF+1
 	!WORD	$0080
 	!WORD	0
 CLOSEPARMS !BYTE 1
@@ -218,19 +249,18 @@ OPTBL 	!WORD	ZERO,ADD,SUB,MUL,DIV,MOD,INCR,DECR		; 00 02 04 06 08 0A 0C 0E
 ;*
 ;* CLEAR COMMAND LINE LENGTH BYTE IF CALLED FROM 'BYE'
 ;*
-BYE	LDY	DEFCMD
-        STY     $0280		; SET DEFAULT COMMAND WHEN CALLED FROM 'BYE'
--	LDA	DEFCMD,Y
-	STA	$0280,Y
+BYE	JMP	CPYCMD
+DEFCMD	!FILL	63		; AT $D103 IN LC MEMORY
+CPYCMD	LDY	DEFCMD
+-	LDA	DEFCMD,Y	; SET DEFAULT COMMAND WHEN CALLED FROM 'BYE'
+	STA	STRBUF,Y
 	DEY
-	BNE	-
-	BEQ	CMDEXEC
-DEFCMD	!BYTE	3
-	!TEXT	"CMD"
+	BPL	-
 ;*
 ;* MOVE REST OF CMD FROM LANGUAGE CARD
 ;*
-CMDEXEC	STY	SRCL
+CMDEXEC	LDY	#$00
+	STY	SRCL
 	STY	DSTL
 	LDA	#$D2
 	STA	SRCH