GET.NSC.TIME

Disassembly listing with machine code of No Slot Clock util 
by Saint John Morrison produced on Merlin using Printfiler.


                1
                2    POINTER  =     $42
                3    ZP_TIME  =     $44
                4
                5    CLK_JMP  =     $BF06
                6    PRO_DATE =     $BF90
                7    PRO_TIME =     $BF92
                8    MACHID   =     $BF98
                9
                10   PRBYTE   =     $FDDA
                11   COUT     =     $FDED
                12   CROUT    =     $FD8E
                13
                14            ORG   $2000
                15
                16   * First, find out if we have a Zip Chip. If so,
                17   * save its status.
2000: 20 2B 20  18   START    JSR   HAS_ZIP?
2003: D0 03     19            BNE   :NOZIP
2005: 8E 5A C0  20            STX   $C05A      ; scramble it
                21   * make sure we have a NSC somewhere
2008: 20 56 20  22   :NOZIP   JSR   HAS_NSC?
200B: D0 06     23            BNE   :NOTHING
200D: 20 12 21  24            JSR   CLOCK      ; yes!
2010: 4C 20 20  25            JMP   RESET
                26   * Nope!
2013: A2 00     27   :NOTHING LDX   #$00
2015: BD 3E 22  28   :TLP     LDA   FAIL_TXT,X
2018: F0 06     29            BEQ   RESET
201A: 20 ED FD  30            JSR   COUT
201D: E8        31            INX
201E: D0 F5     32            BNE   :TLP
                33   * Reset Zip to previous parameters and exit
2020: 20 2B 20  34   RESET    JSR   HAS_ZIP?   ; unlock again
2023: D0 05     35            BNE   :RTS
2025: A9 A5     36            LDA   #$A5       ; lock the chip
2027: 8D 5A C0  37            STA   $C05A
202A: 60        38   :RTS     RTS
                39
                40   * Returns EQ for yes, NE for no
202B: A9 5A     41   HAS_ZIP? LDA   #$5A
202D: A2 03     42            LDX   #$03
202F: 8D 5A C0  43   :LP      STA   $C05A
2032: CA        44            DEX
2033: 10 FA     45            BPL   :LP
2035: 8D 5B C0  46            STA   $C05B
                47   * cache code
2038: A2 00     48            LDX   #$00
203A: BD 00 20  49   :CACHE   LDA   START,X
203D: E8        50            INX
203E: D0 FA     51            BNE   :CACHE
                52   * Is there a chip here?
2040: AD 5C C0  53            LDA   $C05C
2043: 49 FF     54            EOR   #$FF
2045: 8D 5C C0  55            STA   $C05C
2048: CD 5C C0  56            CMP   $C05C
204B: D0 08     57            BNE   :NOPE
204D: 49 FF     58            EOR   #$FF
204F: 8D 5C C0  59            STA   $C05C
2052: CD 5C C0  60            CMP   $C05C
2055: 60        61   :NOPE    RTS
                62
                63   * From here doesn't have to be cached
                64   * Returns EQ for yes, NE for no (X=slot number -1)
2056: A2 08     65   HAS_NSC? LDX   #$08
2058: 8E DB 20  66   :LP      STX   :X+1       ; slot being tested
205B: 20 6A 20  67            JSR   :NSCTEST   ; returns carry set for
205E: B0 07     68            BCS   :OK        ; found one!
2060: AE DB 20  69            LDX   :X+1
2063: CA        70            DEX
2064: 10 F2     71            BPL   :LP
2066: 60        72            RTS              ; with "NE" set
2067: A9 00     73   :OK      LDA   #$00
2069: 60        74            RTS              ; with "EQ" set
                75   * Set up parameters
206A: BD DC 20  76   :NSCTEST LDA   :READ0_L,X
206D: 8D D8 21  77            STA   READ0+1
2070: BD E5 20  78            LDA   :READ0_H,X
2073: 8D D9 21  79            STA   READ0+2
2076: BD EE 20  80            LDA   :READ1_L,X
2079: 8D DC 21  81            STA   READ1+1
207C: BD F7 20  82            LDA   :READ1_H,X
207F: 8D DD 21  83            STA   READ1+2
2082: BD 00 21  84            LDA   :READ2_L,X
2085: 8D 2A 22  85            STA   READ2+1
2088: BD 09 21  86            LDA   :READ2_H,X
208B: 8D 2B 22  87            STA   READ2+2
208E: A9 00     88            LDA   #$00       ; comparison counts
2090: 8D D8 20  89            STA   :CMP0
2093: 8D D9 20  90            STA   :CMP0+1
2096: 20 D5 21  91            JSR   READ_NSC
2099: AD 36 22  92            LDA   BCD_TIME   ; years
209C: 8D D6 20  93            STA   :TEMP0
209F: AD 3D 22  94            LDA   BCD_TIME+7 ; centiseconds
20A2: 8D D7 20  95            STA   :TEMP0+1
20A5: A2 63     96            LDX   #$63       ; do 100 times
20A7: 8E DA 20  97   :LP0     STX   :X
20AA: 20 D5 21  98            JSR   READ_NSC
20AD: AD 36 22  99            LDA   BCD_TIME   ; years
20B0: CD D6 20  100           CMP   :TEMP0
20B3: F0 03     101           BEQ   *+5
20B5: EE D8 20  102           INC   :CMP0
20B8: AD 3D 22  103           LDA   BCD_TIME+7 ; centiseconds
20BB: CD D7 20  104           CMP   :TEMP0+1
20BE: F0 03     105           BEQ   *+5
20C0: EE D9 20  106           INC   :CMP0+1
20C3: AE DA 20  107           LDX   :X
20C6: CA        108           DEX
20C7: 10 DE     109           BPL   :LP0
                110  * Now, the YEAR should have 0 differences, the
                111  * CENTISECONDS should have at least one.
20C9: 18        112           CLC
20CA: AD D8 20  113           LDA   :CMP0
20CD: D0 06     114           BNE   :RTS
20CF: AD D9 20  115           LDA   :CMP0+1
20D2: F0 01     116           BEQ   :RTS
20D4: 38        117           SEC              ; found!
20D5: 60        118  :RTS     RTS
                119
                120  * Variables and tables used
20D6: 00 00     121  :TEMP0   DS    2
20D8: 00 00     122  :CMP0    DS    2
20DA: 00 00     123  :X       DS    2
20DC: FF FF FF  124  :READ0_L HEX   FFFFFFFFFFFFFF2121
20DF: FF FF FF FF
20E3: 21 21
20E5: CF CF CF  125  :READ0_H HEX   CFCFCFCFCFCFCFC0C0
20E8: CF CF CF CF
20EC: C0 C0
20EE: 00 00 00  126  :READ1_L HEX   000000000000000707
20F1: 00 00 00 00
20F5: 07 07
20F7: C1 C2 C3  127  :READ1_H HEX   C1C2C3C4C5C6C7C0C0
20FA: C4 C5 C6 C7
20FE: C0 C0
2100: FF FF FF  128  :READ2_L HEX   FFFFFFFFFFFFFF0606
2103: FF FF FF FF
2107: 06 06
2109: CF CF CF  129  :READ2_H HEX   CFCFCFCFCFCFCFC0C0
210C: CF CF CF CF
2110: C0 C0
                130
                131  * Do the time setting for ProDOS, and print the time.
2112: A2 00     132  CLOCK    LDX   #$00
2114: BD 4E 22  133  :CLP     LDA   OK_TXT,X
2117: F0 06     134           BEQ   :CX
2119: 20 ED FD  135           JSR   COUT
211C: E8        136           INX
211D: D0 F5     137           BNE   :CLP
211F: AD 3A 22  138  :CX      LDA   BCD_TIME+4 ; hours
2122: 20 DA FD  139           JSR   PRBYTE
2125: A9 BA     140           LDA   #":"
2127: 20 ED FD  141           JSR   COUT
212A: AD 3B 22  142           LDA   BCD_TIME+5 ; minutes
212D: 20 DA FD  143           JSR   PRBYTE
2130: A9 A0     144           LDA   #" "
2132: 20 ED FD  145           JSR   COUT
2135: AD 38 22  146           LDA   BCD_TIME+2 ; date
2138: 20 DA FD  147           JSR   PRBYTE
213B: A9 A0     148           LDA   #" "
213D: 20 ED FD  149           JSR   COUT
2140: AD 37 22  150           LDA   BCD_TIME+1 ; month
2143: 20 C0 21  151           JSR   NORMALIZ
2146: 38        152           SEC
2147: E9 01     153           SBC   #$01
2149: 0A        154           ASL              ; *4
214A: 0A        155           ASL
214B: AA        156           TAX
214C: A0 00     157           LDY   #$00
214E: BD 55 22  158  :MLP     LDA   MONTH,X
2151: 20 ED FD  159           JSR   COUT
2154: E8        160           INX
2155: C8        161           INY
2156: C0 04     162           CPY   #$04
2158: 90 F4     163           BLT   :MLP
215A: AD 36 22  164           LDA   BCD_TIME   ; year
215D: 20 DA FD  165           JSR   PRBYTE
2160: 20 8E FD  166           JSR   CROUT
                167
                168  * Store in global page
2163: AD 38 22  169           LDA   BCD_TIME+2 ; date
2166: 20 C0 21  170           JSR   NORMALIZ
2169: 8D 90 BF  171           STA   PRO_DATE
                172
216C: AD 37 22  173           LDA   BCD_TIME+1 ; month
216F: 20 C0 21  174           JSR   NORMALIZ
2172: 0A        175           ASL              ; *32
2173: 0A        176           ASL
2174: 0A        177           ASL
2175: 0A        178           ASL
2176: 0A        179           ASL
2177: 08        180           PHP              ; carry goes into year
2178: 0D 90 BF  181           ORA   PRO_DATE
217B: 8D 90 BF  182           STA   PRO_DATE
217E: AD 36 22  183           LDA   BCD_TIME   ; year
2181: 20 C0 21  184           JSR   NORMALIZ
2184: 28        185           PLP
2185: 2A        186           ROL
2186: 8D 91 BF  187           STA   PRO_DATE+1
2189: AD 3A 22  188           LDA   BCD_TIME+4 ; hours
218C: 10 0F     189           BPL   :AM        ; in 24-hour mode
218E: 29 7F     190           AND   #$7F       ; get rid of 12/24 bit
2190: AA        191           TAX
2191: 29 20     192           AND   #$20       ; find AM/PM
2193: 08        193           PHP
2194: 8A        194           TXA
2195: 29 1F     195           AND   #$1F
2197: 28        196           PLP
2198: F0 03     197           BEQ   :AM
219A: 18        198           CLC
219B: 69 12     199           ADC   #$12       ; add 12
219D: 20 C0 21  200  :AM      JSR   NORMALIZ
21A0: 8D 93 BF  201           STA   PRO_TIME+1
21A3: AD 3B 22  202           LDA   BCD_TIME+5 ; minutes
21A6: 20 C0 21  203           JSR   NORMALIZ
21A9: C9 3C     204           CMP   #$3C       ; =60?
21AB: 90 02     205           BLT   :MIN
21AD: A9 3B     206           LDA   #$3B       ; set to 59
21AF: 8D 92 BF  207  :MIN     STA   PRO_TIME
                208
21B2: A9 60     209           LDA   #$60       ; RTS
21B4: 8D 06 BF  210           STA   CLK_JMP
21B7: AD 98 BF  211           LDA   MACHID
21BA: 09 01     212           ORA   #$01       ; set "has a clock" bit
21BC: 8D 98 BF  213           STA   MACHID
21BF: 60        214           RTS              ; all done!
                215
21C0: 48        216  NORMALIZ PHA
21C1: 29 0F     217           AND   #$0F
21C3: AA        218           TAX
21C4: 68        219           PLA
21C5: 4A        221           LSR
21C6: 4A        221           LSR
21C7: 4A        221           LSR
21C8: 4A        221           LSR
21C9: A8        223           TAY
21CA: 8A        224           TXA
21CB: 88        225  :LP      DEY
21CC: 10 01     226           BPL   :C
21CE: 60        227           RTS
21CF: 18        228  :C       CLC
21D0: 69 0A     229           ADC   #$0A
21D2: 4C CB 21  230           JMP   :LP
                231
                232  * Swiped liberally from a disassembled CLOCKREAD
                233  * Count on 100 clock cycles (more like 200)
21D5: 08        234  READ_NSC PHP
21D6: 78        235           SEI
21D7: AD FF CF  236  READ0    LDA   $CFFF      ; reset ROM space
21DA: 48        237           PHA              ; and save status
21DB: 8D 00 C1  238  READ1    STA   $C100      ; select card ROM
21DE: AD 04 C8  239           LDA   $C804
                240
                241  * Save ten bytes from POINTER on
21E1: A2 0A     242           LDX   #$0A
21E3: B5 41     243  :LP      LDA   POINTER-1,X
21E5: 48        244           PHA
21E6: CA        245           DEX
21E7: D0 FA     246           BNE   :LP
                247
21E9: A9 2E     248           LDA   #<IDBYTES
21EB: 85 42     249           STA   POINTER
21ED: A9 22     250           LDA   #>IDBYTES
21EF: 85 43     251           STA   POINTER+1  ; hi byte
                252
                253  * I'm assuming that this is a mysterious sequence
                254  * that must be followed verbatim if anything is to
                255  * be accomplished
21F1: A0 07     256           LDY   #$07
21F3: B1 42     257  :LP0     LDA   (POINTER),Y
21F5: 38        258           SEC
21F6: 6A        259           ROR
21F7: 48        260  :LP1     PHA
21F8: A9 00     261           LDA   #$00
21FA: 2A        262           ROL
21FB: AA        263           TAX
21FC: BD 00 C8  264           LDA   $C800,X
21FF: 68        265           PLA
2200: 4A        266           LSR
2201: D0 F4     267           BNE   :LP1
2203: 88        268           DEY
2204: 10 ED     269           BPL   :LP0
                270
                271  * Get the time from the registers
2206: A2 07     272           LDX   #$07       ; byte counter
2208: A0 07     273  :T_LP0   LDY   #$07       ; bit counter
220A: AD 04 C8  274  :T_LP1   LDA   $C804
220D: 6A        275           ROR
220E: 76 44     276           ROR   ZP_TIME,X
2210: 88        277           DEY
2211: 10 F7     278           BPL   :T_LP1
2213: B5 44     279           LDA   ZP_TIME,X
2215: 9D 36 22  280           STA   BCD_TIME,X
2218: CA        281           DEX
2219: 10 ED     282           BPL   :T_LP0
                283
                284  * Restore saved ZP area
221B: A2 00     285           LDX   #$00
221D: 68        286  :RESTORE PLA
221E: 95 42     287           STA   POINTER,X
2220: E8        288           INX
2221: E0 0A     289           CPX   #$0A
2223: 90 F8     290           BLT   :RESTORE
                291
                292  * Reset $C800 space if we were using a slot-based chip
2225: 68        293           PLA
2226: 2A        294           ROL
2227: B0 03     295           BCS   *+5
2229: 8D FF CF  296  READ2    STA   $CFFF
222C: 28        297           PLP
222D: 60        298           RTS
                299
                300  ********************************
                301  * Data                         *
                302  ********************************
                303
                304  * ID bytes for NSC
222E: 5C A3 3A  305  IDBYTES  HEX   5C,A3,3A,C5,5C,A3,3A,C5
2231: C5 5C A3 3A
2235: C5
                306
2236: 00 00 00  307  BCD_TIME DS    8
2239: 00 00 00 00
223D: 00
                308
223E: 8D        309  FAIL_TXT HEX   8D
223F: CE EF A0  310           ASC   "No NSC found.",8D00
2242: CE D3 C3 A0
2246: E6 EF F5 EE
224A: E4 AE 8D 00
                311
224E: 8D        312  OK_TXT   HEX   8D
224F: C9 F4 A7  313           ASC   "It's ",00
2252: F3 A0 00
                314
2255: CA E1 EE  315  MONTH    ASC   "Jan Feb Mar Apr May Jun "
2258: A0 C6 E5 E2
225C: A0 CD E1 F2
2260: A0 C1 F0 F2
2264: A0 CD E1 F9
2268: A0 CA F5 EE
226C: A0
226D: CA F5 EC  316           ASC   "Jul Aug Sep Oct Nov Dec "
2270: A0 C1 F5 E7
2274: A0 D3 E5 F0
2278: A0 CF E3 F4
227C: A0 CE EF F6
2280: A0 C4 E5 E3
2284: A0


--End assembly, 645 bytes, Errors: 0


Symbol table - alphabetical order:

BCD_TIME=$2236      CLK_JMP =$BF06      CLOCK   =$2112      COUT    =$FDED
CROUT   =$FD8E      FAIL_TXT=$223E      HAS_NSC?=$2056      HAS_ZIP?=$202B
IDBYTES =$222E      MACHID  =$BF98      MONTH   =$2255      NORMALIZ=$21C0
OK_TXT  =$224E      POINTER =$42        PRBYTE  =$FDDA      PRO_DATE=$BF90
PRO_TIME=$BF92      READ0   =$21D7      READ1   =$21DB      READ2   =$2229
READ_NSC=$21D5      RESET   =$2020      START   =$2000      ZP_TIME =$44



Symbol table - numerical order:

POINTER =$42        ZP_TIME =$44        START   =$2000      RESET   =$2020
HAS_ZIP?=$202B      HAS_NSC?=$2056      CLOCK   =$2112      NORMALIZ=$21C0
READ_NSC=$21D5      READ0   =$21D7      READ1   =$21DB      READ2   =$2229
IDBYTES =$222E      BCD_TIME=$2236      FAIL_TXT=$223E      OK_TXT  =$224E
MONTH   =$2255      CLK_JMP =$BF06      PRO_DATE=$BF90      PRO_TIME=$BF92
MACHID  =$BF98      CROUT   =$FD8E      PRBYTE  =$FDDA      COUT    =$FDED