#[1] DotB1_patch_2018.asm 3 0000 .bank $0 4 5 ; 6 ; Dead of the Brain #1 Patches to print function 7 ; 8 9 10 ; 11 ; First, Font will occupy space from $DB00 to $DFFF 12 ; (0x17380 on disk) 13 ; 14 DB80 FONT EQU $DB80 15 16 ;----------- 17 ;PATCH1 in code: 18 ; 19 ; Catch print function just as it reads a text (non-control) byte 20 ; The patch should decide whether to continue to treat it like Kanji 21 ; or like ASCII 22 ; 23 24 C4A0 .ORG $C4A0 25 ; This is 0x15CA0 on disk 26 27 C4A0 .code 28 00:C4A0 4C 60 DA JMP PTCH1 29 30 ;----------- 31 ;PATCH2 in code: 32 ; 33 C4CF .ORG $C4CF 34 ; This is 0x15CCF on disk 35 00:C4CF 4C 78 DA JMP PTCH2 36 37 ;----------- 38 ;PATCH3 in code: 39 ; 40 ; Catch print function as it prepares to fetch the graphic representation 41 ; of the caharacter to print. The implication is that the patch will 42 ; supply an alternate 16x16 kanji graphic (but only left half) for ASCII 43 ; characters 44 ; 45 C785 .ORG $C785 46 ; This is 0x15F85 on disk 47 48 00:C785 4C 8B DA JMP PTCH3 49 50 ;----------- 51 ;PATCH4 in code: 52 ; 53 ; Catch print function as it decides how to deal with bit-shift and 54 ; new tile allocation, before mixing the new graphic tiles with the 55 ; old ones. 56 ; The implication here is that ASCII is 8-bits wide, not 12 (or 16) 57 ; 58 C7BD .ORG $C7BD 59 ; This is 0x15FBD on disk 60 61 00:C7BD 4C 9C DA JMP PTCH4 62 63 ;----------- 64 ;PATCH5 in code: 65 ; 66 ; Catch print function as it tries to adjust the "residual bit shift" 67 ; value, based on prior value and character width. 68 ; The implication is that original code assumed 12 pixels wide, but 69 ; ASCII characters will be 8 pixels wide. 70 ; 71 C8ED .ORG $C8ED 72 ; This is 0x160ED on disk 73 74 00:C8ED 4C B2 DA JMP PTCH5 75 76 77 ; 78 ;------------ 79 ; These are variables in use by the routine (so I don't need to steal 80 ; any from the existing routine) 81 ; 82 83 DA5C .ORG $DA5C 84 00:DA5C CHARIND: 85 00:DA5C 00 .DB 0 86 87 00:DA5D 00 TMPVLO: .DB 0 88 00:DA5E 00 TMPVHI: .DB 0 89 90 00:DA5F ASCIFLAG: 91 00:DA5F 00 .DB 0 92 93 ;----------- 94 ;PATCH1 itself: 95 96 DA60 .ORG $DA60 97 ; This is 0x17260 on disk 98 99 00:DA60 8D 26 35 PTCH1: STA $3526 ; original instruction 100 00:DA63 C9 80 CMP #$80 ; is it <#$80 (i.e. ASCII) ? 101 00:DA65 90 06 BCC PTCH1A ; YES, goto PTCH1A 102 00:DA67 9C 5F DA STZ ASCIFLAG ; NO, clear the ASCIFLAG 103 00:DA6A 4C A3 C4 JMP $C4A3 ; continue as it nothing happened 104 105 00:DA6D A9 01 PTCH1A: LDA #1 ; set the ASCIFLAG 106 00:DA6F 8D 5F DA STA ASCIFLAG 107 00:DA72 AD 26 35 LDA $3526 ; get value back into 'A' as needed 108 00:DA75 4C AD C4 JMP $C4AD ; continue (increment pointer) 109 110 ;---------- 111 ;PATCH2 itself: 112 ; .ORG $???? 113 00:DA78 AD 5F DA PTCH2: LDA ASCIFLAG ; check if we are using ASCII 114 00:DA7B F0 08 BEQ PTCH2Z ; if not, return 115 00:DA7D AD 1A 35 LDA $351A ; instead of comparing against #$0C, 116 00:DA80 C9 08 CMP #$08 ; compare against width of #$08 117 00:DA82 4C D4 C4 JMP $C4D4 118 119 00:DA85 AD 1A 35 PTCH2Z: LDA $351A ; original instruction 120 00:DA88 4C D2 C4 JMP $C4D2 ; continue as if nothing happened 121 122 123 ;---------- 124 ;PATCH3 itself: 125 ; .ORG $???? 126 127 00:DA8B AD 5F DA PTCH3: LDA ASCIFLAG ; check if we are using ASCII 128 00:DA8E F0 06 BEQ PTCH3Z ; if not, return 129 00:DA90 20 DB DA JSR ASCISTUP ; do the ASCII SETUP 130 00:DA93 4C AB C7 JMP $C7AB ; go back to just after Kanji call 131 132 00:DA96 AD 25 35 PTCH3Z: LDA $3525 ; original instruction 133 00:DA99 4C 88 C7 JMP $C788 ; continue as if nothing happened 134 135 ;---------- 136 ; PATCH4 itself: 137 ; .ORG $???? 138 139 00:DA9C 8D 7A 35 PTCH4: STA $357A ; original instruction 140 00:DA9F AD 5F DA LDA ASCIFLAG ; check if we are using ASCII 141 00:DAA2 F0 08 BEQ PTCH4Z ; if not, return 142 00:DAA4 AD 7A 35 LDA $357A 143 00:DAA7 C9 08 CMP #$08 ; compare against #$08, not #$0C 144 00:DAA9 4C C2 C7 JMP $C7C2 145 146 00:DAAC AD 7A 35 PTCH4Z: LDA $357A ; If not ASCII, return to original stream 147 00:DAAF 4C C0 C7 JMP $C7C0 148 149 150 ;---------- 151 ; PATCH5 itself: 152 ; .ORG $???? 153 154 00:DAB2 AD 5F DA PTCH5: LDA ASCIFLAG ; check if we are using ASCII 155 00:DAB5 F0 1E BEQ PTCH5Z ; if not, return 156 00:DAB7 AD 1A 35 LDA $351A 157 00:DABA C9 08 CMP #$08 158 00:DABC 90 11 BCC PTCH5X ; if less than 159 00:DABE C9 0C PTCH5A: CMP #$0C 160 00:DAC0 D0 07 BNE PTCH5B 161 00:DAC2 73 29 35 TII $3529,$3549,$0020 00:DAC5 49 35 20 00:DAC8 00 162 00:DAC9 38 PTCH5B: SEC 163 00:DACA E9 08 SBC #$08 164 00:DACC 4C F7 C8 JMP $C8F7 ; return to middle of code sequence (STA $351A) 165 166 00:DACF 18 PTCH5X: CLC ; if less than 167 00:DAD0 69 08 ADC #$08 ; add 8 instead of value in $3518 (from PRINTFLAGS) 168 00:DAD2 4C 06 C9 JMP $C906 ; return to middle of code sequence (STA $351A) 169 170 00:DAD5 AD 1A 35 PTCH5Z: LDA $351A ; original instruction 171 00:DAD8 4C F0 C8 JMP $C8F0 172 173 174 00:DADB ASCISTUP: ; loads ASCII character into $3526 as if it were Kanji 175 00:DADB DA PHX 176 00:DADC 5A PHY 177 00:DADD AD 26 35 LDA $3526 ; get ASCII value 178 00:DAE0 38 SEC 179 00:DAE1 E9 20 SBC #$20 ; font starts at $20 (space) 180 00:DAE3 8D 5C DA STA CHARIND 181 182 00:DAE6 AD 5C DA LDA CHARIND ; use CHARIND as index for ASCII value 183 184 00:DAE9 8D 5D DA STA TMPVLO ; get index and place into TMPVLO/HI to calculate offset 185 00:DAEC 9C 5E DA STZ TMPVHI ; from bbase of FONT definition 186 187 00:DAEF 0E 5D DA ASL TMPVLO ; Double the offset 188 00:DAF2 2E 5E DA ROL TMPVHI 189 190 00:DAF5 AD 5D DA LDA TMPVLO ; Add character index again (now, 3 times original) 191 00:DAF8 18 CLC 192 00:DAF9 6D 5C DA ADC CHARIND 193 00:DAFC 8D 5D DA STA TMPVLO 194 00:DAFF AD 5E DA LDA TMPVHI 195 00:DB02 69 00 ADC #$00 196 00:DB04 8D 5E DA STA TMPVHI 197 198 00:DB07 0E 5D DA ASL TMPVLO ; Double the index again (now 6 times orig) 199 00:DB0A 2E 5E DA ROL TMPVHI 200 201 00:DB0D 0E 5D DA ASL TMPVLO ; Double the index again (now 12 times orig) 202 00:DB10 2E 5E DA ROL TMPVHI 203 204 00:DB13 A9 80 LDA #LOW(FONT) ; add address of font def'n table 205 00:DB15 18 CLC 206 00:DB16 6D 5D DA ADC TMPVLO 207 00:DB19 8D 5D DA STA TMPVLO 208 00:DB1C 85 70 STA <$70 209 00:DB1E A9 DB LDA #HIGH(FONT) 210 00:DB20 6D 5E DA ADC TMPVHI 211 00:DB23 8D 5E DA STA TMPVHI 212 00:DB26 85 71 STA <$71 213 214 00:DB28 C2 CLY 215 00:DB29 82 CLX 216 00:DB2A B1 70 FNTLP LDA [$70],Y 217 00:DB2C 9D 29 35 STA $3529,X 218 00:DB2F E8 INX 219 00:DB30 9E 29 35 STZ $3529,X 220 00:DB33 E8 INX 221 00:DB34 C8 INY 222 00:DB35 C0 0C CPY #12 ; 12 decimal (font height) 223 00:DB37 D0 F1 BNE FNTLP 224 00:DB39 9E 29 35 FNTLP1 STZ $3529,X 225 00:DB3C E8 INX 226 00:DB3D E0 20 CPX #$20 227 00:DB3F D0 F8 BNE FNTLP1 228 229 00:DB41 7A PLY 230 00:DB42 FA PLX 231 00:DB43 60 RTS 232