#FILE: $RCSfile: undocops.txt $ #DESC: The 'Documented' Undocumented Illegal 6809 Opcodes #REV: $Revision: 1.1 $ #DATE: $Date: 1995/08/18 14:39:40 $ #AUTHOR: Graham E. Kinns #DISCLAIMER: All information provided as is etc. #ARCHIVE: This file is part of the DRGNINFO collection of Dragon info files #CONTACT: Comments, bugs, revisions, suggestions to Dragon@grempc.demon.co.uk #HISTORY: 1.0 27/01/94 - Initial results typed up #RCSID: $Id: undocops.txt 1.1 1995/08/18 14:39:40 Graham Exp $ These results were found by direct experiment on a 6809E in my Dragon using Mike Kerry's DreamBug monitor on Rom. All cycles are assumed - I don't have any way of measuring them at present. Page 1 ====== Op Mne Mode ~ # Comment 01 NEG Direct 6 2 Same as op $00 (NEG <$xx) 02 NEG/COM Direct 6 2 If cc.c = 0 then NEG <$xx (op $00) If cc.c = 1 then COM <$xx (op $03) (<$xx) = not(<$xx) + not(cc.c) 05 LSR Direct 6 2 Same as op $04 (LSR <$xx) 0b DEC Direct 6 2 Same as op $0A (DEC <$xx) 14 ?? } Seem to be interrupt related 15 ?? } 18 ?? 1b ?? 38 CWAI ?? ? 2 or something similar. Doesn't alter any regs except CC. 3e RESET Inherent - 1 Forces internal Reset, disables interrupts. 41 NEGA Inherent 2 1 Same as 40 42 COMA Inherent 2 1 Same as 43 45 LSRA Inherent 2 1 Same as 44 4b DECA Inherent 2 1 Same as 4a 4e CLRA Inherent 2 1 Same as 4f 51 NEGB Inherent 2 1 Same as 50 52 COMB Inherent 2 1 Same as 53 55 LSRB Inherent 2 1 Same as 54 5b DECB Inherent 2 1 Same as 5a 5e CLRB Inherent 2 1 Same as 5f 61 NEG Indexed 6+ 2+ Same as 60 - not tested 62 COM Indexed 6+ 2+ Same as 63 - not tested 65 LSR Indexed 6+ 2+ Same as 64 - not tested 6b DEC Indexed 6+ 2+ Same as 6a - not tested 71 NEG Extended 7 3 Same as 70 - not tested 72 COM Extended 7 3 Same as 73 - not tested 75 LSR Extended 7 3 Same as 74 - not tested 7b DEC Extended 7 3 Same as 7a - not tested 87 ?? 8f ?? c7 ?? cd ?? cf ?? Page 2 (10xx) ====== 1000 - 100f 1010 [Page switch 2][Page switch 2] - flowchart in data sheet suggests any page switch code after the intial one are ignored 1011 [Page switch 2][Page switch 3] - same as [Page switch 2] 1012 - 101f 1030 - 103e 1040 - 1082 1084 - 108b 108d 108f - 1092 1094 - 109b 109d 10a0 - 10a2 10a4 - 10ab 10ad 10b0 - 10b2 10b4 - 10bb 10bd 10c0 - 10cd 10cf - 10dd 10e0 - 10ed 10f0 - 10ff Page 3 (11xx) ====== 1100 - 110f 1110 [Page switch 3][Page switch 2] - same as [Page sw 3] 1111 [Page switch 3][Page switch 3] - same as [Page sw 3] 1112 - 113e 1140 - 1182 1184 - 118b 118d - 1192 1194 - 119b 119d - 11a2 11a4 - 11ab 11ad - 11b2 11b4 - 11bb 11bd - 11ff