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EXTENDED BASIC UNRAVELLED IIAPPENDIX GEXTENDED BASIC 1.0 DIFFERENCESORIGIN:SPECTRAL ASSOCREVISED:12/26/1999 WALTER K ZYDHEKthe ASCII to floating point conversion in PRINT USING.917D962C-962D96A3-96B3Change op code address field from #'9'+3(1.0) to #'9'+1(1.1)Change instruction from LDA #6(1.0) to LDA GRPRAM(1.1).This change allows the start of the first graphic pageto be determined by the value in the direct page variableGRPRAM (start of graphic RAM) rather than theabsolue value of 6 which is valid for an ExtendedBasic ONLY system.Patch the PCLEAR command to fix the PCLEAR bug (seeFigure G3). This patch merely rearranges existingcode to allow for the call (JSR L80D0) to the routinewhich will adjust the BASIC input pointer.96A3 1025 1DA3 LBLO LB44A IF TRYING TO CLEAR LESS THAN ENDOF CURRENT PAGE = 'ILLEGAL FUNCTION CALL'96A7 93 19 SUBD TXTTAB SUBTRACT START OF RAM96A9 D3 1B ADDD VARTAB ADD END OF BASIC PROGRAM96AB 1F 01 TFR D,X X=TOP OF PCLEARED SPACE+SIZE OF BASICPROGRAM96AD C3 00C8 ADDD #200 ADD 200 - LEAVE SOME ROOM FOR STACK96B0 93 21 SUBD FRETOP SUBTRACT OUT START OF CLEARED SPACE96B2 24 B9 BCC L966D NO ROOM LEFT - 'ILLEGAL FUNCTION CALL'Figure G3 - Version 1.0 codeG2