stuff

diff --git a/ROM-2003/vend.asm b/ROM-2003/vend.asm
index 576324f..e0c0428 100644 (file)
--- a/ROM-2003/vend.asm
+++ b/ROM-2003/vend.asm
@@ -1,4 +1,4 @@
-;0000   
+;0000   set to 1 at the end of a keypad read and turned off at the next rti
 ;0001   coin mask? (cf 0x001a, 0x3000, 0xc430)
 ;0003   global only used in jump71
 ;0005   number of motors we have
@@ -8,7 +8,7 @@
 ;0009
 ;000a   
 ;000c
-;0012   another buffer for 1800
+;0012   another buffer for 1800 - what change to give?
 ;0013
 ;0014   buffer for 3800 register  
 ;0015
@@ -44,6 +44,7 @@
 ;005b   last known keypad row 0 state
 ;005a - result of number to string operations (jump55)
 ;    005f   
+;0067   working space of 0bc0
 ;0073   
 ;0076-0077 word
 ;007f   
@@ -60,7 +61,15 @@
 ;0bbd   
 ;0bd8   related to 0017 and 0021 (only lower 3 bits used)
 ;0bd9   also related
-;0bc0   bit 0, 2, 1, 3
+;0bc0   machine capabilities flags
+;         bit0: have dumb mech
+;         bit1: 
+;         bit2: have card reader
+;         bit3: have bill validator
+;         bit4: link master - price holding enabled
+;         bit5: link master - price display enabled
+;         bit6: have $1 changer
+;         bit7: free vend
 ;0bc1   error status:  (from jump72)
 ;         bit0: changer powerup
 ;         bit1: card powerup
@@ -69,14 +78,33 @@
 ;         bit4: coin jam
 ;         bit5: bad sensor
 ;         bit6: tube error
-;0bc2 - 0bce SCI read into these locations
-;0bd
+;
+; SCI read buffer:
+;
+;0bc2  multiplied by 10^0bc3 and stored into 0baa
+;0bc3  10 is raise to the power of this number shr 4, and multiplied by 0baa
+;0bc4  index of something
+;0bc5  index of something else
+;0bc6  index of another thing
+;0bc7 word number of something
+;0bc8  
+;0bc9 word number of something else
+;0bca  
+;0bcb word number of another thing
+;0bcc  
+;0bcd word number of another else
+;0bce  
+;
 ;0bc4   array index into 0bc7
 ;0bc5
 ;0bc6   another array index into 0bc7
 ;0bc7 word array
 ;
-;0be1
+;0bdd   value of coin mech quarters
+;0bdf   value of coin mech dimes
+;0be1   value of coin mech nickels
+
+;
 ;0bd7   init'd to 0x01
 ;0bd8   init'd to 0x04
 ;0bd9   init'd to 0x02
@@ -86,10 +114,22 @@
 ;
 ;0cbc   serial number (string)
 ;0ccc   machine ID (string)
-;0ce7   audit number (1-bit)
+;0ce7   audit number (word)
+;
 ;0cd9   counter of something - reset to 4 on some serial input
 ;0cda   counter of something - reset to 4 on some serial input
 ;0cdb   also counts something - reset to 4 on some serial input
+
+;0ce9   value or number of $1 coins
+;0ceb   value or number of 20c coins
+;0ced   value or number of 10c coins
+;0cef   value or number of 5c coins
+
+;0cdc   number of value of $1 coins
+;0cdb   number or value of 20c coin
+;0cda   number or value of 10c coins
+;0cd9   number or value of 5c coins
+
 ;0dff - 0e04 keypad buffer - most recent in 0e04
 ;0e05   array index of the array to follow
 ;0e06 - ?? array of digits*10
@@ -409,7 +449,7 @@ jump72:
 ; initial menu when door opens?
 8100 F6 00 1D        ...   ldab 001d
 8103 C4 10           ..    andb #10
-8105 27 3D           '=    beq 3d
+8105 27 3D           '=    beq 3d       ; to 8144
 8107 BD D6 52        ..R   jsr d652            ;jump5
 810A CE 00 1D        ...   ldx #001d
 810D 1D 00 10        ...   bclr 00,x, #10
@@ -431,6 +471,7 @@ jump72:
 813B 7F 0E 02        ...   clr 0e02
 813E 7F 0E 03        ...   clr 0e03
 8141 7F 0E 04        ...   clr 0e04
+;
 8144 F6 00 42        ..B   ldab 0042
 8147 C1 0B           ..    cmpb #0b
 8149 26 0F           &.    bne 0f
@@ -916,6 +957,7 @@ jump14:
 85BE 39              9     rts 
 
 jump28:
+; drop some change out of the changer?
 85BF F6 00 12        ...   ldab 0012
 85C2 C4 1E           ..    andb #1e     ; 00011110
 85C4 4F              O     clra 
@@ -934,7 +976,7 @@ jump28:
 85EC 7F 00 2C        ..,   clr 002c
 85EF F6 0C D9        ...   ldab 0cd9
 85F2 27 03           '.    beq 03
-85F4 7A 0C D9        z..   dec 0cd9
+85F4 7A 0C D9        z..   dec 0cd9     ; decrement number of 5c coins
 85F7 BD 97 F6        ...   jsr 97f6            ;jump27
 85FA CC 01 5E        ..^   ldd #015e
 85FD BD E5 71        ..q   jsr e571            ;msdelay
@@ -949,7 +991,7 @@ jump28:
 8616 7F 00 2C        ..,   clr 002c
 8619 F6 0C DA        ...   ldab 0cda
 861C 27 03           '.    beq 03
-861E 7A 0C DA        z..   dec 0cda
+861E 7A 0C DA        z..   dec 0cda     ; decrement number of 10c coins
 8621 BD 97 F6        ...   jsr 97f6            ;jump27
 8624 CC 01 5E        ..^   ldd #015e
 8627 BD E5 71        ..q   jsr e571            ;msdelay
@@ -964,7 +1006,7 @@ jump28:
 8640 7F 00 2C        ..,   clr 002c
 8643 F6 0C DB        ...   ldab 0cdb
 8646 27 03           '.    beq 03
-8648 7A 0C DB        z..   dec 0cdb
+8648 7A 0C DB        z..   dec 0cdb     ; decrement number of 20c coins
 864B BD 97 F6        ...   jsr 97f6            ;jump27
 864E CC 01 5E        ..^   ldd #015e
 8651 BD E5 71        ..q   jsr e571            ;msdelay
@@ -979,7 +1021,7 @@ jump28:
 8669 7F 00 2C        ..,   clr 002c
 866C F6 0C DC        ...   ldab 0cdc
 866F 27 03           '.    beq 03
-8671 7A 0C DC        z..   dec 0cdc
+8671 7A 0C DC        z..   dec 0cdc     ; decrement number of $1 coins
 8674 BD 97 F6        ...   jsr 97f6            ;jump27
 8677 CC 01 5E        ..^   ldd #015e
 867A BD E5 71        ..q   jsr e571            ;msdelay
@@ -3579,6 +3621,7 @@ jump142:
 9E88 39              9     rts 
 
 jump100:
+; print out information to display
 9E89 BD BE 4B        ..K   jsr be4b            ;displayblank
 9E8C F6 00 48        ..H   ldab 0048
 9E8F 4F              O     clra 
@@ -3824,7 +3867,7 @@ A0CC 4F              O     clra
 A0CD BD A3 1A        ...   jsr a31a            ;jump93
 A0D0 38              8     pulx 
 A0D1 7E A1 C4        ~..   jmp a1c4            ;goto19
-A0D4 CC B3 F2        ...   ldd #b3f2
+A0D4 CC B3 F2        ...   ldd #b3f2    ; "DIMES"
 A0D7 BD C0 BA        ...   jsr c0ba            ;display:
 A0DA 7E A1 C4        ~..   jmp a1c4            ;goto19
 A0DD FE 0C ED        ...   ldx 0ced
@@ -3834,7 +3877,7 @@ A0E4 4F              O     clra
 A0E5 BD A3 1A        ...   jsr a31a            ;jump93
 A0E8 38              8     pulx 
 A0E9 7E A1 C4        ~..   jmp a1c4            ;goto19
-A0EC CC B4 04        ...   ldd #b404
+A0EC CC B4 04        ...   ldd #b404    ; "NICKELS"
 A0EF BD C0 BA        ...   jsr c0ba            ;display:
 A0F2 7E A1 C4        ~..   jmp a1c4            ;goto19
 A0F5 FE 0C EF        ...   ldx 0cef
@@ -4080,6 +4123,7 @@ A318 38              8     pulx
 A319 39              9     rts 
 
 jump93:
+; write number to display
 A31A 37              7     pshb 
 A31B 36              6     psha 
 A31C 30              0     tsx 
@@ -4257,6 +4301,7 @@ A455 BD A3 6C        ..l   jsr a36c               ;jump81
 A458 39              9     rts 
 
 jump110:
+; some sort of defaults setting loading? plays with 0067 an awful lot
 A459 3C              <     pshx 
 A45A F6 00 67        ..g   ldab 0067
 A45D C4 02           ..    andb #02
@@ -7384,28 +7429,28 @@ B91C 7F 00 2C        ..,   clr 002c
 B91F BD BE 01        ...   jsr be01            ;jump70 write to display
 B922 C6 0A           ..    ldab #0a
 B924 F7 00 2C        ..,   stab 002c
-B927 7E BA 81        ~..   jmp ba81            ;goto27
+B927 7E BA 81        ~..   jmp ba81            ;goto27 - return
 goto25:
 B92A F6 0E 6D        ..m   ldab 0e6d
 B92D C1 01           ..    cmpb #01
 B92F 27 03           '.    beq 03
-B931 7E BA 81        ~..   jmp ba81            ;goto27
+B931 7E BA 81        ~..   jmp ba81            ;goto27 - return
 B934 F6 0E 00        ...   ldab 0e00
 B937 C1 05           ..    cmpb #05
 B939 27 03           '.    beq 03
-B93B 7E BA 81        ~..   jmp ba81            ;goto27
+B93B 7E BA 81        ~..   jmp ba81            ;goto27 - return
 B93E F6 0E 01        ...   ldab 0e01
 B941 C1 05           ..    cmpb #05
 B943 27 03           '.    beq 03
-B945 7E BA 81        ~..   jmp ba81            ;goto27
+B945 7E BA 81        ~..   jmp ba81            ;goto27 - return
 B948 F6 0E 02        ...   ldab 0e02
 B94B C1 05           ..    cmpb #05
 B94D 27 03           '.    beq 03
-B94F 7E BA 81        ~..   jmp ba81            ;goto27
+B94F 7E BA 81        ~..   jmp ba81            ;goto27 - return
 B952 F6 00 12        ...   ldab 0012
 B955 C4 20           .     andb #20     ; test the door switch
 B957 26 03           &.    bne 03
-B959 7E BA 81        ~..   jmp ba81            ;goto27
+B959 7E BA 81        ~..   jmp ba81            ;goto27 - return
 B95C F6 0E 04        ...   ldab 0e04
 B95F C1 05           ..    cmpb #05
 B961 26 79           &y    bne 79
@@ -7463,22 +7508,26 @@ B9CE 7F 00 2C        ..,   clr 002c
 B9D1 BD BE 01        ...   jsr be01            ;jump70 - display
 B9D4 C6 1E           ..    ldab #1e
 B9D6 F7 00 2C        ..,   stab 002c
-B9D9 7E BA 81        ~..   jmp ba81            ;goto27
+B9D9 7E BA 81        ~..   jmp ba81            ;goto27 - return
+;
 B9DC F6 0E 04        ...   ldab 0e04
 B9DF C1 01           ..    cmpb #01
 B9E1 27 0A           '.    beq 0a
 B9E3 F6 0E 04        ...   ldab 0e04
 B9E6 C1 02           ..    cmpb #02
 B9E8 27 03           '.    beq 03
-B9EA 7E BA 81        ~..   jmp ba81            ;goto27
+B9EA 7E BA 81        ~..   jmp ba81            ;goto27 - return
+;
 B9ED F6 0E 03        ...   ldab 0e03
 B9F0 C1 00           ..    cmpb #00
 B9F2 22 03           ".    bhi 03
-B9F4 7E BA 81        ~..   jmp ba81            ;goto27
+B9F4 7E BA 81        ~..   jmp ba81            ;goto27 - return
+;
 B9F7 F6 0E 03        ...   ldab 0e03
 B9FA C1 05           ..    cmpb #05
 B9FC 26 03           &.    bne 03
-B9FE 7E BA 81        ~..   jmp ba81            ;goto27
+B9FE 7E BA 81        ~..   jmp ba81            ;goto27 - return
+;
 BA01 F6 0E 03        ...   ldab 0e03
 BA04 C1 07           ..    cmpb #07
 BA06 24 79           $y    bcc 79
@@ -8673,6 +8722,7 @@ C323 01              .     nop
 C324 39              9     rts 
 
 jump64:
+; has a good long chat to the bill validator
 C325 F6 10 00        ...   ldab 1000
 C328 C4 01           ..    andb #01
 C32A 26 13           &.    bne 13
@@ -8795,14 +8845,15 @@ C452 F7 30 00        .0.   stab 3000    ; changer outputs again
 C455 39              9     rts 
 
 jump47:
+; coin have something to do with coin counting?
 C456 FC 00 40        ..@   ldd 0040
 C459 26 03           &.    bne 03
-C45B 7E C5 C6        ~..   jmp c5c6            ;goto39
+C45B 7E C5 C6        ~..   jmp c5c6            ;goto39 - unset 0x30 in 0021 & return
 C45E CE 00 1A        ...   ldx #001a
 C461 1C 00 01        ..    bset 00,x, #01
 C464 F6 00 1A        ...   ldab 001a
 C467 F7 30 00        .0.   stab 3000   ; changer accept off
-C46A CC 03 E8        ...   ldd #03e8
+C46A CC 03 E8        ...   ldd #03e8    ; 1000
 C46D BD E5 71        ..q   jsr e571            ;msdelay
 goto42:
 C470 FC 00 40        ..@   ldd 0040
@@ -8912,7 +8963,7 @@ C577 5F              _     clrb
 C578 4F              O     clra 
 C579 FD 00 40        ..@   std 0040
 goto41:
-C57C CC 01 2C        ..,   ldd #012c
+C57C CC 01 2C        ..,   ldd #012c    ;300 ms
 C57F BD E5 71        ..q   jsr e571            ;msdelay
 C582 F6 00 1B        ...   ldab 001b
 C585 C4 20           .     andb #20
@@ -8921,7 +8972,7 @@ C589 CE 00 1A        ...   ldx #001a
 C58C 1D 00 01        ..    bclr 00,x, #01
 C58F F6 00 1A        ...   ldab 001a
 C592 F7 30 00        .0.   stab 3000   ; changer accept' low
-C595 CC 00 0C        ...   ldd #000c
+C595 CC 00 0C        ...   ldd #000c    ; 12 ms
 C598 BD E5 71        ..q   jsr e571            ;msdelay
 C59B CE 00 1A        ...   ldx #001a
 C59E 1C 00 01        ..    bset 00,x, #01
@@ -8929,7 +8980,7 @@ C5A1 F6 00 1A        ...   ldab 001a
 C5A4 F7 30 00        .0.   stab 3000   ; changer accept' high
 C5A7 CC 00 23        ..#   ldd #0023
 C5AA BD E5 71        ..q   jsr e571            ;msdelay
-C5AD 7E C4 70        ~.p   jmp c470            ;goto42
+C5AD 7E C4 70        ~.p   jmp c470            ;goto42 - loop
 goto40:
 C5B0 F6 0B C0        ...   ldab 0bc0
 C5B3 C4 04           ..    andb #04
@@ -8944,8 +8995,8 @@ goto39:
 C5C6 CE 00 21        ..!   ldx #0021
 C5C9 1D 00 10        ...   bclr 00,x, #10
 C5CC CE 00 1B        ...   ldx #001b
-C5CF 1D 00           ..    bclr add,x 00,x
-C5D1 20 39            9    bra 39
+C5CF 1D 00           ..    bclr 00,x, #20
+C5D2 39              .     rts
 
 jump6:
 C5D3 F6 00 15        ...   ldab 0015
@@ -9350,7 +9401,7 @@ C943 25 12           %.    bcs 12       ; to c957
 C945 CE 00 17        ...   ldx #0017
 C948 1D 00 04        ...   bclr 00,x, #04
 C94B 7F 00 08        ...   clr 0008
-C94E BD CE 48        ..H   jsr ce48            ;jump48
+C94E BD CE 48        ..H   jsr ce48            ;jump48 - update values?
 C951 7F 00 2C        ..,   clr 002c
 C954 7E CA 5C        ~.\   jmp ca5c            ;goto50 - clean exit
 ;
@@ -9425,9 +9476,9 @@ C9DD 20 7A            z    bra 7a       ;goto51 - inc 0008 & clean exit
 C9DF F6 10 2F        ../   ldab 102f    ; read SCI data
 C9E2 F7 0B C4        ...   stab 0bc4
 C9E5 F6 0B C4        ...   ldab 0bc4
-C9E8 C1 80           ..    cmpb #80
+C9E8 C1 80           ..    cmpb #80     ; if == 128
 C9EA 26 05           &.    bne 05
-C9EC C6 0F           ..    ldab #0f
+C9EC C6 0F           ..    ldab #0f     ; put 15 => 0bc4
 C9EE F7 0B C4        ...   stab 0bc4
 C9F1 20 66            f    bra 66       ;goto51 - inc 0008 & clean exit
 ;
@@ -9531,7 +9582,7 @@ CABA 1C 00           ..    bset 00,x, #20
 CABD CE 00 1B        ...   ldx #001b
 CAC0 1D 00 40        ...   bclr 00,x, #40
 CAC3 7F 00 25        ..%   clr 0025
-CAC6 7E CB 64        ~.d   jmp cb64            ;goto53
+CAC6 7E CB 64        ~.d   jmp cb64            ;goto53 - cleanup & exit
 ;
 CAC9 F6 00 17        ...   ldab 0017
 CACC C4 08           ..    andb #08
@@ -9965,7 +10016,7 @@ CE39 20 0B            .    bra 0b       ; to ce46 (exit)
 goto54: ; just swallow two bytes?
 CE3B F6 10 2E        ...   ldab 102e    ; SCI Status
 CE3E 30              0     tsx 
-CE3F E7 00           ..    stab 00,x
+CE3F E7 00           ..    stab 00,x    ; store into stack variable
 CE41 F6 10 2F        ../   ldab 102f    ; read SCI data
 CE44 E7 00           ..    stab 00,x
 goto47:
@@ -10459,18 +10510,18 @@ D213 F6 00 1F        ...   ldab 001f
 D216 C4 04           ..    andb #04
 D218 26 12           &.    bne 12
 D21A F6 0B C0        ...   ldab 0bc0
-D21D C4 10           ..    andb #10
+D21D C4 10           ..    andb #10     ; am i link master?
 D21F 26 0B           &.    bne 0b
 D221 CE 00 00        ...   ldx #0000
 D224 3C              <     pshx 
 D225 FC 00 44        ..D   ldd 0044
-D228 BD BE 9E        ...   jsr be9e            ;jump50
+D228 BD BE 9E        ...   jsr be9e            ;jump50 - write slot & price to screen?
 D22B 38              8     pulx 
 D22C BD D3 11        ...   jsr d311            ;jump30 - test position exists
 D22F 83 00 00        ...   subd #0000
 D232 27 13           '.    beq 13
 D234 F6 00 06        ...   ldab 0006
-D237 BD D4 68        ..h   jsr d468            ;jump51
+D237 BD D4 68        ..h   jsr d468            ;jump51 - lookup in 0800 table & and with 8000
 D23A 83 00 00        ...   subd #0000
 D23D 27 05           '.    beq 05
 D23F 8D BC           ..    bsr bc       ;jump90
@@ -11051,13 +11102,13 @@ D66A 39              9     rts
 
 jump107:
 D66B F6 0B C0        ...   ldab 0bc0
-D66E C4 08           ..    andb #08
-D670 27 07           '.    beq 07
+D66E C4 08           ..    andb #08   ; we have a bill validator?
+D670 27 07           '.    beq 07     ; if not, to d679
 D672 F6 00 7D        ..}   ldab 007d
 D675 27 02           '.    beq 02
-D677 20 F9            .    bra f9
+D677 20 F9            .    bra f9     ; to d672 - wait for a bill?
 D679 F6 00 15        ...   ldab 0015
-D67C 2D 77           -w    blt 77
+D67C 2D 77           -w    blt 77     ; return
 D67E FC 00 40        ..@   ldd 0040
 D681 F3 00 3E        ..>   addd 003e
 D684 B3 00 0F        ...   subd 000f
@@ -11108,6 +11159,7 @@ D6F5 39              9     rts
 
 jump106:
 ; puts (0cdb+0bdd)+(0cda*0bdf)+(0cd9*0be1) => 0bef
+; calculates how much money we have in the coin mech!!!!
 D6F6 F6 0C DB        ...   ldab 0cdb
 D6F9 4F              O     clra 
 D6FA 37              7     pshb 
@@ -11871,7 +11923,7 @@ DCC8 37              7     pshb
 DCC9 36              6     psha 
 DCCA CE E1 00        ...   ldx #e100
 DCCD 3C              <     pshx 
-DCCE CC 05 F5        ...   ldd #05f5
+DCCE CC 05 F5        ...   ldd #05f5  ; 100000000
 DCD1 37              7     pshb 
 DCD2 36              6     psha 
 DCD3 30              0     tsx 
@@ -12167,12 +12219,12 @@ DF4B 26 20           &     bne 20
 DF4D F6 00 1B        ...   ldab 001b
 DF50 C4 40           .@    andb #40
 DF52 27 19           '.    beq 19
-DF54 BD D6 52        ..R   jsr d652            ;jump5
+DF54 BD D6 52        ..R   jsr d652            ;jump5 - pulse bill acceptor
 DF57 FC 00 40        ..@   ldd 0040
 DF5A 26 05           &.    bne 05
 DF5C FC 00 3E        ..>   ldd 003e
 DF5F 27 03           '.    beq 03
-DF61 BD DB 44        ..D   jsr db44            ;jump104
+DF61 BD DB 44        ..D   jsr db44            ;jump104 - say thanks
 DF64 BD D6 6B        ..k   jsr d66b            ;jump107
 DF67 CE 00 1B        ...   ldx #001b
 DF6A 1D 00 40        ...   bclr 00,x, #40
@@ -12297,7 +12349,7 @@ E074 BD E7 C7        ...   jsr e7c7             ;jump114
 E077 F6 00 06        ...   ldab 0006
 E07A C1 59           .Y    cmpb #59     ; 89
 E07C 26 06           &.    bne 06
-E07E BD DE 09        ...   jsr de09            ;jump119
+E07E BD DE 09        ...   jsr de09            ;jump119  - display machine id
 E081 7E E5 5E        ~.^   jmp e55e            ;goto74
 E084 F6 00 06        ...   ldab 0006
 E087 BD D4 68        ..h   jsr d468            ;jump51
@@ -12587,7 +12639,7 @@ E2F2 24 15           $.    bcc 15
 E2F4 F6 00 11        ...   ldab 0011
 E2F7 C4 10           ..    andb #10
 E2F9 26 0E           &.    bne 0e
-E2FB BD DB 44        ..D   jsr db44            ;jump104
+E2FB BD DB 44        ..D   jsr db44            ;jump104 - say thanks
 E2FE CE 00 1B        ...   ldx #001b
 E301 1D 00 40        ...   bclr 00,x, #40
 E304 7F 00 25        ..%   clr 0025
@@ -12922,7 +12974,7 @@ E5C0 FC 00 3B        ..;   ldd 003b
 E5C3 27 06           '.    beq 06      ; to e5cb
 E5C5 CC 02 33        ..3   ldd #0233
 E5C8 FD 00 3B        ..;   std 003b
-E5CB C6 02           ..    ldab #02
+E5CB C6 02           ..    ldab #02    ; make a beep
 E5CD F7 00 33        ..3   stab 0033
 E5D0 39              9     rts 
 
@@ -14747,7 +14799,7 @@ F413 38              8     pulx
 F414 39              9     rts 
 
 jump112:
-; print a report?
+; print a report to printer
 F415 F6 0B C0        ...   ldab 0bc0
 F418 C4 02           ..    andb #02
 F41A 27 15           '.    beq 15
@@ -15023,7 +15075,7 @@ F6DF BD F1 5B        ..[   jsr f15b             ;jump53
 F6E2 F6 00 19        ...   ldab 0019
 F6E5 C4 40           .@    andb #40
 F6E7 26 07           &.    bne 07
-F6E9 FE 0C E7        ...   ldx 0ce7
+F6E9 FE 0C E7        ...   ldx 0ce7     ;increment the audit number?
 F6EC 08              .     inx 
 F6ED FF 0C E7        ...   stx 0ce7
 F6F0 CE 00 1D        ...   ldx #001d
@@ -15044,10 +15096,10 @@ F717 39              9     rts
 
 rti:
 F718 3C              <     pshx 
-F719 F6 0B C0        ...   ldab 0bc0    
+F719 F6 0B C0        ...   ldab 0bc0    ; if we have a bill validator
 F71C C4 08           ..    andb #08
 F71E 27 03           '.    beq 03
-F720 BD C3 25        ..%   jsr c325            ;jump64
+F720 BD C3 25        ..%   jsr c325            ;jump64 - go query the bill validator
 F723 7C 00 0C        |..   inc 000c
 F726 F6 00 0C        ...   ldab 000c
 F729 C1 02           ..    cmpb #02
@@ -15318,9 +15370,12 @@ F94F F7 00 35        ..5   stab 0035
 ;
 ; end of power line test
 ;
+;
+; chat to the bill validator if we need to
+;
 F952 F6 0B C0        ...   ldab 0bc0
 F955 C4 08           ..    andb #08
-F957 27 16           '.    beq 16       ; to f96f
+F957 27 16           '.    beq 16       ; to f96f if no bill validator
 F959 CE 00 02        ...   ldx #0002
 F95C 3C              <     pshx 
 F95D CC 10 00        ...   ldd #1000
@@ -15354,10 +15409,11 @@ F99C 26 03           &.    bne 03
 F99E BD D6 F6        ...   jsr d6f6            ;jump106
 F9A1 F6 00 12        ...   ldab 0012
 F9A4 C4 20           .     andb #20     ; test door switch
-F9A6 27 08           '.    beq 08
+F9A6 27 08           '.    beq 08       ; to f9b0
 F9A8 F6 00 35        ..5   ldab 0035
 F9AB 26 03           &.    bne 03
 F9AD 7E FA 79        ~.y   jmp fa79            ;goto83
+;
 F9B0 CE 00 1F        ...   ldx #001f
 F9B3 1D 00 04        ...   bclr 00,x, #04
 F9B6 CE 00 1D        ...   ldx #001d
@@ -15652,6 +15708,7 @@ FC23 31              1     ins
 FC24 39              9     rts 
 
 jump85:
+; long addition function?
 FC25 3C              <     pshx 
 FC26 30              0     tsx 
 FC27 E3 06           ..    addd 06,x