; season - junior
;
; author: hackbard@hackdaworld.dyndns.org
;


; at90s2313
; setup:
; vcc card --- atmel vcc
; vcc cam  --- 
; rst cam  --- atmel int0 (pd2)
; rst card --- atmel (pd4)
; clk card -\ 
;            -  atmel t1 (pd5)
; clk cam  -/
; gnd card --- gnd cam --- atmel gnd
; i/o card --- atmel icp (pd6)
; i/o cam  --- atmel int1 (pd3)

.include "../include/2313def.inc"

; functions by now:
;
; stupid mode only by now. just see what cam/card do and redirect
; this to card/cam.
;
; next implementation:
; 
; try to read one byte of card/cam communication and output via uart.
; output time information in some way.
;
; future:
;
; buffer/parse whole strings and decide whether to send to card or not.

; some defines
; ------------

; baudrate = clock freq / etu
; std smartcard etu: 372
; other smartcards: 625
.define clock 8000000
.define clk_h 4000000
.define etu 625
.define etu_h 312
.define baudrate 5 ; UBRR value for 76800 bits/s (8mhz clock)

; names for registers
.define tmp r16
.define bitcount r17
.define tmp1 r18
.define tmp2 r19
.define byte r20
.define overflow_counter r21
.define one r1
.define zero r0


;
; programm code
; -------------

;
; interrupt vectors:
;

; reset
rjmp INIT

; int0
rjmp RST_CAM

; int1
rjmp REC_CAM

; timer/counter capt 1
rjmp REC_CARD

; timer/counter compare
reti

; timer/counter overflow 1
rjmp CLK_OVERFLOW

; timer/counter overflow 0
reti

; uart rx complete
reti

; uart data register empty
rjmp UART_OUT

; uart tx complete
reti

; analog comparator
reti

;
; init routine
;

INIT:

; set stackpointer
ldi tmp,low(RAMEND)
out SPL,tmp

; enable interrupts int0,int1
ldi tmp,((1<<INT0)|(1<<INT1))
out GIMSK,tmp
; int0/1 setup
ldi tmp,((1<<ISC01)|(0<<ISC00)|(1<<ISC11)|(0<<ISC10))
out MCUCR,tmp

; enable t/c overflow interrupt and icp
ldi tmp,((1<<TOIE1)|(1<<TICIE1))
out TIMSK,tmp
; setup t/c and icp
ldi tmp,((1<<CS12)|(1<<CS11)|(1<<CS10)|(1<<ICNC1)|(1<<ICES1))
out TCCR1B,tmp

; configure uart - interrupt enabled when i/o
ldi tmp,baudrate
out UBRR,tmp
sbi UCR,TXEN

; init registers
ldi bitcounter,0 
ldi byte,0
ldi overflow_counter,0
ldi tmp1,0
ldi tmp2,0 
ldi tmp,1
mov one,tmp
ldi tmp,0
mov zero,tmp

; enable interrupts (global)
sei

; jump to mainloop
rjmp MAIN

;
; main routine
;

MAIN:

rjmp MAIN

;
; rec_card routines
;

REC_CARD:

; decide what to do
sbic PORTD,PD6
rjmp REC_CARD_HIGH
rjmp REC_CARD_LOW

REC_CARD_HIGH:

; save counter
in r24,ICR1L
in r25,ICR1H

; output high on port to cam
sbi PORTD,PD3

; toggle icp sense
cbi TCCR1B,ICES1
;in r16,TCCR1B
;cbr r16,ICES1
;out TCCR1B,r16

; status tu submit
ldi r26,1

; enable uart dre interrupt
sbi UCR,UDRIE

reti

REC_CARD_LOW:

; save counter
in r27,ICR1L
in r28,ICR1H

; output low on port to cam
cbi PORTD,PD3

; toggle icp sense
sbi TCCR1B,ICES1

; status to submit
ldi r26,0

; enable uart dre interrupt
sbi UCR,UDRIE

reti

;
; rec_cam routines
;

REC_CAM:

; decide what to do
sbic PORTD,PD3
rjmp REC_CAM_HIGH
rjmp REC_CAM_LOW

REC_CAM_HIGH:

; output high on port to card
sbi PORTD,PD6

; toggle int1 sense
in r16,MCUCR
cbr r16,ISC10
out MCUCR,r16

reti

REC_CAM_LOW:

; output low on port to card
cbi PORTD,PD6

; toggle int 1 sense
in r16,MCUCR
sbr r16,ISC10
out MCUCR,r16

reti

;
; t1_overflow routine
;

T1_OVERFLOW:

add r22,r1 ; inc counter overflow register

reti

;
; rst_cam routine
;

RST_CAM:

; decide what to do
sbic PORTD,PD2
rjmp RST_CAM_HIGH
rjmp RST_CAM_LOW

RST_CAM_HIGH:

; output high on rst port to card
sbi PORTD,PD4

; toggle int0 sense
in r16,MCUCR
cbr r16,ISC00
out MCUCR,r16

reti

RST_CAM_LOW:

; output low on rst port to cam
cbi PORTD,PD4

; toggle int0 sense
in r16,MCUCR
sbr r16,ISC00
out MCUCR,r16

reti

;
; uart_out routines
;

UART_OUT:

;
; hier weiter ...
;