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6502_EhBASIC_V2.22
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RAM above code / Ibuff above EhBASIC patch breaks STR$() 

User mgcaret provided a fix
This commit is contained in:
Klaus2m5 2018-01-21 10:10:07 +01:00
parent 0a70ad5bd0
commit eeab9858ff
2 changed files with 15 additions and 6 deletions
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13
bugsnquirks.txt
View File

@ -31,6 +31,9 @@ place and only a pointer needs to be set to the string location.
There is a bug in EhBASIC to determine where the string is.
!! The original version of this patch broke the number to string conversion as
in STR$(). Github user mgcaret provided a fix included in version 2 !!
LAB_20DC
STX Sendh ; save string end high byte
LDA ssptr_h ; get string start high byte
@ -42,14 +45,16 @@ below RAM_base. The fix requires the input buffer not to cross a page boundary:
LAB_20DC
STX Sendh ; save string end high byte
LDA ssptr_h ; get string start high byte
; *** begin RAM above code / Ibuff above EhBASIC patch ***
; *** begin RAM above code / Ibuff above EhBASIC patch V2 ***
; *** replace
; CMP #>Ram_base ; compare with start of program memory
; BCS LAB_RTST ; branch if not in utility area
; *** with
BEQ LAB_MVST ; fix STR$() using page zero via LAB_296E
CMP #>Ibuffs ; compare with location of input buffer page
BNE LAB_RTST ; branch if not in utility area
; *** end RAM above code / Ibuff above EhBASIC patch ***
LAB_MVST
; *** end RAM above code / Ibuff above EhBASIC patch V2 ***
3. Output of some functions limited to integers is negative.
@ -163,7 +168,7 @@ LAB_142P
DEC Bpntrl ; allow for increment
RTS
The conditional in the patch abover requires Ibuffs to be known at path 1 during
The conditional in the patch above requires Ibuffs to be known at pass 1 during
assembly. The standard definition of Ibuffs does not satisfy this requirement.
We need to replace it like below:
@ -188,6 +193,6 @@ during the inner loop if not in direct mode, but direct mode (Clineh = $FF) is
only cleared later in the same loop.
The fix is in the patched folder (version 2.22p2). The continue counter is now
always saved and the decission to continue is postponed until the CONT statement
always saved and the decision to continue is postponed until the CONT statement
is executed and based on the fact that the continue pointer must not point to
the input buffer in run mode.

8
patched/basic.asm
View File

@ -22,6 +22,8 @@
; tabs converted to spaces, tabwidth=6
; 2.22p2 fixed can't continue error on 1st statement after direct mode
; changed INPUT to throw "break in line ##" on empty line input
; 2.22p3 fixed RAM above code / Ibuff above EhBASIC patch breaks STR$()
; fix provided by github user mgcaret
; zero page use ..
@ -4412,14 +4414,16 @@ LAB_20D0
LAB_20DC
STX Sendh ; save string end high byte
LDA ssptr_h ; get string start high byte
; *** begin RAM above code / Ibuff above EhBASIC patch ***
; *** begin RAM above code / Ibuff above EhBASIC patch V2 ***
; *** replace
; CMP #>Ram_base ; compare with start of program memory
; BCS LAB_RTST ; branch if not in utility area
; *** with
BEQ LAB_MVST ; fix STR$() using page zero via LAB_296E
CMP #>Ibuffs ; compare with location of input buffer page
BNE LAB_RTST ; branch if not in utility area
; *** end RAM above code / Ibuff above EhBASIC patch ***
LAB_MVST
; *** end RAM above code / Ibuff above EhBASIC patch V2 ***
; string in utility area, move to string memory
TYA ; copy length to A