#include processor p12f629 ; --------------------------------------------------------------------- ; SNES CIC clone for PIC Microcontroller (key mode only) ; ; Copyright (C) 2010 by Maximilian Rehkopf (ikari_01) ; This software is part of the sd2snes project. ; ; This program is free software; you can redistribute it and/or modify ; it under the terms of the GNU General Public License as published by ; the Free Software Foundation; version 2 of the License only. ; ; This program is distributed in the hope that it will be useful, ; but WITHOUT ANY WARRANTY; without even the implied warranty of ; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the ; GNU General Public License for more details. ; ; You should have received a copy of the GNU General Public License ; along with this program; if not, write to the Free Software ; Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA ; ; --------------------------------------------------------------------- ; ; pin configuration: (cartridge pin) [key CIC pin] ; ; ,---_---. ; +5V (27,58) [16] |1 8| GND (5,36) [8] ; CIC clk (56) [6] |2 7| CIC data i/o 0 (55) [2] ; status out |3 6| CIC data i/o 1 (24) [1] ; /PAIR |4 5| CIC slave reset (25) [7] ; `-------' ; ; ; Status out can be connected to a LED. It indicates: ; ; state | output ; -------------------------+---------------------------- ; OK or no lock CIC | high ; error | low ; SuperCIC pair mode | 148.75kHz / 50% duty cycle ; ; In case lockout fails, the region is switched automatically and ; will be used after the next reset. ; ; The /PAIR pin can be used to enable or disable SuperCIC pair mode. ; It can be tied low or high to statically enable or disable pair mode ; detection, or connected to a switch or MCU to dynamically enable pair ; mode detection (it should then be connected to a pull-up resistor to ; Vcc). Pair mode detection can be enabled during operation, ; but pair mode cannot be left until the next power cycle. ; See SuperCIC lock documentation for a more detailed description of ; pair mode. ; ; memory usage: ; ; 0x20 buffer for seed calc and transfer ; 0x21 - 0x2f seed area (lock seed) ; 0x30 buffer for seed calc ; 0x31 - 0x3f seed area (key seed; 0x31 filled in by lock) ; 0x40 - 0x41 buffer for seed calc ; 0x4d buffer for eeprom access ; 0x4e loop variable for longwait ; 0x4f loop variable for wait ; 0x5e SuperCIC pair mode detect (phase 1) ; 0x5f SuperCIC pair mode detect (phase 2) ; --------------------------------------------------------------------- ; ----------------------------------------------------------------------- __CONFIG _EC_OSC & _WDT_OFF & _PWRTE_OFF & _MCLRE_OFF & _CP_OFF & _CPD_OFF ; ----------------------------------------------------------------------- ; code memory org 0x0000 nop nop nop goto init isr org 0x0004 bcf INTCON, 1 ; clear interrupt cause bcf GPIO, 0 bcf GPIO, 1 bsf GPIO, 4 ; LED on clrf 0x5e ; clear pair mode detect clrf 0x5f ; clear pair mode detect bsf 0x5f, 1 ; nop nop nop bsf INTCON, 7 ; re-enable interrupts (ISR will continue as main) goto main init org 0x0010 banksel GPIO clrf GPIO movlw 0x07 ; GPIO2..0 are digital I/O (not connected to comparator) movwf CMCON movlw 0x90 ; global enable interrupts + enable external interrupt movwf INTCON banksel TRISIO movlw 0x2d ; in out in in out in movwf TRISIO movlw 0x24 ; pullups for reset+clk to avoid errors when no CIC in host movwf WPU movlw 0x00 ; 0x80 for global pullup disable movwf OPTION_REG banksel GPIO bsf GPIO, 4 ; LED on idle goto idle ; wait for interrupt from lock main banksel TRISIO bsf TRISIO, 0 bcf TRISIO, 1 banksel GPIO ; --------INIT LOCK SEED (what the lock sends)-------- movlw 0xb movwf 0x21 movlw 0x1 movwf 0x22 movlw 0x4 movwf 0x23 movlw 0xf movwf 0x24 movlw 0x4 movwf 0x25 movlw 0xb movwf 0x26 movlw 0x5 movwf 0x27 movlw 0x7 movwf 0x28 movlw 0xf movwf 0x29 movlw 0xd movwf 0x2a movlw 0x6 movwf 0x2b movlw 0x1 movwf 0x2c movlw 0xe movwf 0x2d movlw 0x9 movwf 0x2e movlw 0x8 movwf 0x2f ; --------INIT KEY SEED (what we must send)-------- banksel EEADR ; D/F411 and D/F413 clrf EEADR ; differ in 2nd seed nibble bsf EECON1, RD ; of key stream, movf EEDAT, w ; restore saved nibble from EEPROM banksel GPIO movwf 0x32 movlw 0xa movwf 0x33 movlw 0x1 movwf 0x34 movlw 0x8 movwf 0x35 movlw 0x5 movwf 0x36 movlw 0xf movwf 0x37 movlw 0x1 movwf 0x38 movwf 0x39 movlw 0xe movwf 0x3a movlw 0x1 movwf 0x3b movlw 0x0 movwf 0x3c movlw 0xd movwf 0x3d movlw 0xe movwf 0x3e movlw 0xc movwf 0x3f ; --------wait for stream ID-------- movlw 0xb5 call wait clrf 0x31 ; clear lock stream ID ; --------lock sends stream ID. 15 cycles per bit-------- ; bsf GPIO, 0 ; (debug marker) ; bcf GPIO, 0 ; btfsc GPIO, 0 ; check stream ID bit bsf 0x31, 3 ; copy to lock seed movlw 0x2 ; wait=3*W+5 call wait ; burn 11 cycles nop nop ; bsf GPIO, 0 ; bcf GPIO, 0 btfsc GPIO, 0 ; check stream ID bit bsf 0x31, 0 ; copy to lock seed movlw 0x2 ; call wait ; burn 11 cycles nop nop ; bsf GPIO, 0 ; bcf GPIO, 0 btfsc GPIO, 0 ; check stream ID bit bsf 0x31, 1 ; copy to lock seed movlw 0x2 ; call wait ; burn 11 cycles nop nop ; bsf GPIO, 0 ; bcf GPIO, 0 btfsc GPIO, 0 ; check stream ID bit bsf 0x31, 2 ; copy to lock seed banksel TRISIO bcf TRISIO, 0 bsf TRISIO, 1 banksel GPIO nop movlw 0x27 ; "wait" 1 call wait ; wait 121 ; --------main loop-------- loop movlw 0x1 loop0 addlw 0x30 ; key stream movwf FSR ; store in index reg loop1 nop nop movf INDF, w ; load seed value movwf 0x20 bcf 0x20, 1 ; clear bit 1 btfsc 0x20, 0 ; copy from bit 0 bsf 0x20, 1 ; (if set) bsf 0x20, 4 ; LED on movf 0x20, w movwf GPIO nop movlw 0x10 movwf GPIO ; reset GPIO movlw 0x14 call wait nop nop nop nop nop btfsc GPIO, 0 ; both pins must be low... goto die btfsc GPIO, 1 ; ...when no bit transfer takes place goto die ; if not -> lock cic error state -> die incf FSR, f ; next one movlw 0xf andwf FSR, w btfss STATUS, Z goto loop1 call mangle call mangle call mangle movlw 0x2 ; wait 10 call wait ; nop nop btfsc 0x37, 0 goto swap banksel TRISIO bcf TRISIO, 0 bsf TRISIO, 1 goto swapskip swap banksel TRISIO bsf TRISIO, 0 bcf TRISIO, 1 nop swapskip banksel GPIO movf 0x37, w andlw 0xf btfss STATUS, Z goto loop0 goto loop ; --------calculate new seeds-------- ; had to be unrolled because PIC has an inefficient way of handling ; indirect access, no post increment, etc. mangle call mangle_lock nop nop mangle_key movf 0x2f, w movwf 0x20 mangle_key_loop addlw 0x1 addwf 0x21, f movf 0x22, w movwf 0x40 movf 0x21, w addwf 0x22, f incf 0x22, f comf 0x22, f movf 0x23, w movwf 0x41 ; store 23 to 41 movlw 0xf andwf 0x23, f movf 0x40, w ; add 40(22 old)+23+#1 and skip if carry andlw 0xf addwf 0x23, f incf 0x23, f btfsc 0x23, 4 goto mangle_key_withskip mangle_key_withoutskip movf 0x41, w ; restore 23 addwf 0x24, f ; add to 24 movf 0x25, w movwf 0x40 ; save 25 to 40 movf 0x24, w addwf 0x25, f movf 0x26, w movwf 0x41 ; save 26 to 41 movf 0x40, w ; restore 25 andlw 0xf ; mask nibble addlw 0x8 ; add #8 to HIGH nibble movwf 0x40 btfss 0x40, 4 ; skip if carry to 5th bit addwf 0x26, w movwf 0x26 movf 0x41, w ; restore 26 addlw 0x1 ; inc addwf 0x27, f ; add to 27 movf 0x27, w ; addlw 0x1 ; inc addwf 0x28, f ; add to 28 movf 0x28, w ; addlw 0x1 ; inc addwf 0x29, f ; add to 29 movf 0x29, w ; addlw 0x1 ; inc addwf 0x2a, f ; add to 2a movf 0x2a, w ; addlw 0x1 ; inc addwf 0x2b, f ; add to 2b movf 0x2b, w ; addlw 0x1 ; inc addwf 0x2c, f ; add to 2c movf 0x2c, w ; addlw 0x1 ; inc addwf 0x2d, f ; add to 2d movf 0x2d, w ; addlw 0x1 ; inc addwf 0x2e, f ; add to 2e movf 0x2e, w ; addlw 0x1 ; inc addwf 0x2f, f ; add to 2f movf 0x20, w ; restore original 0xf andlw 0xf addlw 0xf movwf 0x20 nop nop nop nop nop nop nop nop nop btfss 0x20, 4 ; skip if half-byte carry goto mangle_return ; +2 cycles in return nop goto mangle_key_loop ; 69 when goto, 69 when return ; CIC has 78 -> 9 nops mangle_key_withskip movf 0x41, w ; restore 23 addwf 0x23, f ; add to 23 movf 0x24, w movwf 0x40 ; save 24 to 40 movf 0x23, w addwf 0x24, f movf 0x25, w movwf 0x41 ; save 25 to 41 movf 0x40, w ; restore 24 andlw 0xf ; mask nibble addlw 0x8 ; add #8 to HIGH nibble movwf 0x40 btfss 0x40, 4 ; skip if carry to 5th bit addwf 0x25, w movwf 0x25 movf 0x41, w ; restore 25 addlw 0x1 ; inc addwf 0x26, f ; add to 26 movf 0x26, w ; addlw 0x1 ; inc addwf 0x27, f ; add to 27 movf 0x27, w ; addlw 0x1 ; inc addwf 0x28, f ; add to 28 movf 0x28, w ; addlw 0x1 ; inc addwf 0x29, f ; add to 29 movf 0x29, w ; addlw 0x1 ; inc addwf 0x2a, f ; add to 2a movf 0x2a, w ; addlw 0x1 ; inc addwf 0x2b, f ; add to 2b movf 0x2b, w ; addlw 0x1 ; inc addwf 0x2c, f ; add to 2c movf 0x2c, w ; addlw 0x1 ; inc addwf 0x2d, f ; add to 2d movf 0x2d, w ; addlw 0x1 ; inc addwf 0x2e, f ; add to 2e movf 0x2e, w ; addlw 0x1 ; inc addwf 0x2f, f ; add to 2f movf 0x20, w ; restore original 0xf andlw 0xf addlw 0xf movwf 0x20 bcf GPIO, 0 movf GPIO, w btfss GPIO, 3 bsf GPIO, 0 movwf 0x5e movf GPIO, w movwf 0x5f bcf GPIO, 0 btfsc GPIO, 3 clrf 0x5e nop btfss 0x20, 4 ; skip if half-byte carry goto mangle_return ; +2 cycles in return movf 0x20, w ; restore w (previously destroyed) goto mangle_key_loop mangle_return return ; 73 when goto, 73 when return ; CIC has 84 -> 11 nops mangle_lock movf 0x3f, w movwf 0x30 mangle_lock_loop addlw 0x1 addwf 0x31, f movf 0x32, w movwf 0x40 movf 0x31, w addwf 0x32, f incf 0x32, f comf 0x32, f movf 0x33, w movwf 0x41 ; store 33 to 41 movlw 0xf andwf 0x33, f movf 0x40, w ; add 40(32 old)+33+#1 and skip if carry andlw 0xf addwf 0x33, f incf 0x33, f btfsc 0x33, 4 goto mangle_lock_withskip mangle_lock_withoutskip movf 0x41, w ; restore 33 addwf 0x34, f ; add to 34 movf 0x35, w movwf 0x40 ; save 35 to 40 movf 0x34, w addwf 0x35, f movf 0x36, w movwf 0x41 ; save 36 to 41 movf 0x40, w ; restore 35 andlw 0xf ; mask nibble addlw 0x8 ; add #8 to HIGH nibble movwf 0x40 btfss 0x40, 4 ; skip if carry to 5th bit addwf 0x36, w movwf 0x36 movf 0x41, w ; restore 36 addlw 0x1 ; inc addwf 0x37, f ; add to 37 movf 0x37, w ; addlw 0x1 ; inc addwf 0x38, f ; add to 38 movf 0x38, w ; addlw 0x1 ; inc addwf 0x39, f ; add to 39 movf 0x39, w ; addlw 0x1 ; inc addwf 0x3a, f ; add to 3a movf 0x3a, w ; addlw 0x1 ; inc addwf 0x3b, f ; add to 3b movf 0x3b, w ; addlw 0x1 ; inc addwf 0x3c, f ; add to 3c movf 0x3c, w ; addlw 0x1 ; inc addwf 0x3d, f ; add to 3d movf 0x3d, w ; addlw 0x1 ; inc addwf 0x3e, f ; add to 3e movf 0x3e, w ; addlw 0x1 ; inc addwf 0x3f, f ; add to 3f movf 0x30, w ; restore original 0xf andlw 0xf addlw 0xf movwf 0x30 nop nop nop nop nop nop nop nop nop btfss 0x30, 4 ; skip if half-byte carry goto mangle_return nop goto mangle_lock_loop ; 69 when goto, 69 when return ; CIC has 78 -> 9 nops mangle_lock_withskip movf 0x41, w ; restore 33 addwf 0x33, f ; add to 33 movf 0x34, w movwf 0x40 ; save 34 to 40 movf 0x33, w addwf 0x34, f movf 0x35, w movwf 0x41 ; save 35 to 41 movf 0x40, w ; restore 34 andlw 0xf ; mask nibble addlw 0x8 ; add #8 to HIGH nibble movwf 0x40 btfss 0x40, 4 ; skip if carry to 5th bit addwf 0x35, w movwf 0x35 movf 0x41, w ; restore 35 addlw 0x1 ; inc addwf 0x36, f ; add to 36 movf 0x36, w ; addlw 0x1 ; inc addwf 0x37, f ; add to 37 movf 0x37, w ; addlw 0x1 ; inc addwf 0x38, f ; add to 38 movf 0x38, w ; addlw 0x1 ; inc addwf 0x39, f ; add to 39 movf 0x39, w ; addlw 0x1 ; inc addwf 0x3a, f ; add to 3a movf 0x3a, w ; addlw 0x1 ; inc addwf 0x3b, f ; add to 3b movf 0x3b, w ; addlw 0x1 ; inc addwf 0x3c, f ; add to 3c movf 0x3c, w ; addlw 0x1 ; inc addwf 0x3d, f ; add to 3d movf 0x3d, w ; addlw 0x1 ; inc addwf 0x3e, f ; add to 3e movf 0x3e, w ; addlw 0x1 ; inc addwf 0x3f, f ; add to 3f movf 0x30, w ; restore original 0xf andlw 0xf addlw 0xf movwf 0x30 btfss 0x5e, 1 goto scic_pair_skip1 btfsc 0x5f, 1 goto scic_pair_skip2 btfsc GPIO, 3 goto scic_pair_skip3 goto supercic_pairmode scic_pair_skip1 nop nop scic_pair_skip2 nop nop scic_pair_skip3 nop nop nop nop btfss 0x30, 4 ; skip if half-byte carry goto mangle_return nop goto mangle_lock_loop ; 73 when goto, 73 when return ; CIC has 84 -> 11 nops ; --------wait: 3*(W-1)+7 cycles (including call+return). W=0 -> 256!-------- wait movwf 0x4f wait0 decfsz 0x4f, f goto wait0 return ; --------wait long: 8+(3*(w-1))+(772*w). W=0 -> 256!-------- longwait movwf 0x4e clrw longwait0 call wait decfsz 0x4e, f goto longwait0 return ; --------change region in eeprom and die-------- die movlw 0x3a ;wait 50ms before writing call longwait ;("error" might be due to power loss) banksel EEADR clrw movwf EEADR bsf EECON1, RD movf EEDAT, w banksel GPIO movwf 0x4d btfsc 0x4d, 0 goto die_reg_6 die_reg_9 movlw 0x9 ; died with PAL, fall back to NTSC goto die_reg_cont die_reg_6 movlw 0x6 ; died with NTSC, fall back to PAL die_reg_cont banksel EEADR movwf EEDAT bsf EECON1, WREN die_intloop bcf INTCON, GIE btfsc INTCON, GIE goto die_intloop movlw 0x55 movwf EECON2 movlw 0xaa movwf EECON2 bsf EECON1, WR bsf INTCON, GIE banksel GPIO bcf GPIO, 4 ; --------get caught up-------- die_trap goto die_trap ; ----------------------------------------------------------------------- supercic_pairmode banksel TRISIO bsf TRISIO, 0 bsf TRISIO, 1 banksel GPIO bcf INTCON, GIE supercic_pairmode_loop bsf GPIO, 4 nop nop bcf GPIO, 4 goto supercic_pairmode_loop ; eeprom memory DEEPROM CODE de 0x09 ; D411 (NTSC) end