Replica 1 plus Users Manual FF5F: B9 00 02 NEXTHEX LDA IN,Y Get character for hex test. FF62: 49 B0 EOR #$B0 Map digits to $0-9. FF64: C9 0A CMP #$0A Digit? FF66: 90 06 BCC DIG Yes. FF68: 69 88 ADC #$88 Map letter “A”-“F” to $FA-FF. FF6A: C9 FA CMP #$FA Hex letter? FF6C: 90 11 BCC NOTHEX No, character not hex. FF6E: 0A DIG ASL FF6F: 0A ASL Hex digit to MSD of A. FF70: 0A ASL FF71: 0A ASL FF72: A2 04 LDX #$04 Shift count. FF74: 0A HEXSHIFT ASL Hex digit left, MSB to carry. FF75: 26 28 ROL L Rotate into LSD. FF77: 26 29 ROL H Rotate into MSD’s. FF79: CA DEX Done 4 shifts? FF7A: D0 F8 BNE HEXSHIFT No, loop. FF7C: C8 INY Advance text index. FF7D: D0 E0 BNE NEXTHEX Always taken.
Check next char for hex. FF7F: C4 2A NOTHEX CPY YSAV Check if L, H empty (no hex digits). FF81: F0 97 BEQ ESCAPE Yes, generate ESC sequence. FF83: 24 2B BIT MODE Test MODE byte. FF85: 50 10 BVC NOTSTOR B6=0 STOR 1 for XAM & BLOCK XAM FF87: A5 28 LDA L LSD’s of hex data. FF89: 81 26 STA (STL,X) Store at current ‘store index’. FF8B: E6 26 INC STL Increment store index. FF8D: D0 B5 BNE NEXTITEM Get next item. (no carry). FF8F: E6 27 INC STH Add carry to ‘store index’ high order. FF91: 4C 44 FF TONEXTITEM JMP NEXTITEM Get next command item. FF94: 6C 24 00 RUN JMP (XAML) Run at current XAM index. FF97: 30 2B NOTSTOR BMI XAMNEXT B7=0 for XAM, 1 for BLOCK XAM. FF99: A2 02 LDX #$02 Byte count. FF9B:
B5 27 SETADR LDA L-1,X Copy hex data to FF9D: 95 25 STA STL-1,X ‘store index’. FF9F: 95 23 STA XAML-1,X And to ‘XAM index’. FFA1: CA DEX Next of 2 bytes. FFA2: D0 F7 BNE SETADR Loop unless X=0. FFA4: D0 14 NXTPRNT BNE PRDATA NE means no address to print. FFA6: A9 8D LDA #$8D CR. FFA8: 20 EF FF JSR ECHO Output it. FFAB:A5 25 LDA XAMH ‘Examine index’ high-order byte. FFAD: 20 DC FF JSR PRBYTE Output it in hex format. FFB0: A5 24 LDA XAML Low-order ‘examine index’ byte. FFB2: 20 DC FF JSR PRBYTE Output it in hex format. FFB5: A9 BA LDA #$BA FFB7: 20 EF FF JSR ECHO Output it. FFBA:A9 A0 PRDATA LDA #$A0 Blank. FFBC:20 EF FF JSR ECHO Output it. FFBF:
A1 24 LDA (XAML,X) Get data byte at ‘examine index’. © Briel Computers 2014 page 31