;********************************************************************************
;A digital dial up to 4,5 MHz on AT90S2313 microprocessor
;Quartz of 10 MHz
;The author: Ankudinov A.N. (UA3VVM), mail: ua3vvm@mail.ru
;Cycle of the score is organized on interruption from counter T/C1
;LED indication of 5 discharge, possibility of magnification
;up to 10 discharge. The data on the digital indicator are gated out with usage
;the sequential code.
;********************************************************************************
.cseg
.include "2313def.inc"

.org 	 0 rjmp main_program
.org 	 ovf1addr 	; Interrupt processing from T/C1
	 rjmp calculus

.def zero=r24
.def f3=r3
.def f4=r4 	; To reset bits tov0 having installed it
.def fm1=r10 	; Variables
.def fm2=r11 	; for storage
.def fm3=r12 	; outcome
.def fm4=r13 	; scores of impulses
.def odin=r14 	; the Increment for the score of impulses
.def temp=r9

; ********************************************************************************
; Initial adjustments of the program
; ********************************************************************************

main_program:
	
	 sei 			; To resolve interruptions
	 ldi r16, $df 		; To adjust the beginning of the stack
	 out spl, r16 		; on extremity SRAM
	
	 ldi r18,0b11111 	; Inclusion of the sentry timer on reset through 2.048 second.
	 out wdtcr, r18
	
	 ldi r16,0b00000110 	; Initialization of a port of a terminating connection
	 out ddrb, r16 	; on a terminating connection the 3-wire busbar, bits 1,2 ports "b" works; bits "1" - clocking
			; bits "2" - a data bit

	 clr zero 	; Value "0"
	 clr fm1
	 clr fm2
	 clr fm3
	 clr fm4
	 ldi r19, $01
	 mov odin, r19 	; the Increment for the score of an amount of overfillings TCNT0
	 ldi r18, $02
	 mov f4, r18 	; f4 receives value a bat for adjustment TOV0
	
; *******************************************************************************
; Initialization of counter T/S1 for organization of period of the score of impulses 0.1 second.

	 in r17, timsk 			; To allow
	 ori r17, $80 			; interruptions on
	 out timsk, r17 		; to overflow T/C1
	
	 ldi r16, high ($ffff-15625) 	; To consider from 0 up to 15625
	 out tcnt1h, r16
	 ldi r16, low ($ffff-15625) 	; To consider from 0 up to 15625 out tcnt1l, r16
	
	 ldi r17, $03		 	; the Adjustment of preliminary divider SK/64

; ********************************************************************************
; Initialization of counter T/C0
; Base 32 program of the bit impulse counter
; Countable input terminal T0 of counter T/C0

	 ldi r20, $07 	; the Score of external impulses from input terminal ã0
	 out tifr, f4 	; we Shall reset bits TOV0, having installed it
		
	 out tccr0, r20 	; we Start for counter T/C0 (entry impulses)
	 out tccr1b,r17 	; we Start for counter T/C1 with the adjustment of interruption 0.1 second
	
count: 			; we Start the score of impulses before obtaining interruption from T/C1 cikl:
	 in f3, tifr
	 sbrc f3, $01 	; Skip if bits tov0 it is reset rjmp cikl2 rjmp count cikl2:
	 add fm3, odin 	; If timer T/C0 was overflew to add 1
	 adc fm2, zero 	; To fulfil addition with transposition in high
	 adc fm1, zero 	; discharge& of the counter
	 out tifr, f4 	; we Shall reset(dump) bits TOV0, having installed it
	 rjmp count

; ********************************************************************************
; The handler of the given countable registers

calculus:
	 out tccr0, zero 	; we shall Stop the impulse counter on T/C0
	 in fm4, tcnt0 		; we shall Receive residual from empty timer T/C0 out tcnt0, zero
				; To unset timer T/C0

; *******************************************************************************
; A subprogram of a subtraction of value of intermediate frequency " 500 KHz "
;
; ldi r18, $00 	; In rightmost tens Hz are displayed at period
; ldi r19, $00 	; scores in 0.1 second. 500 KHz = 50000 = C350h
; ldi r20, $C3
; ldi r21, $50
;        
; sub fm4, r21; low
; sbc fm3, r20
; sbc fm2, r19
; sbc fm1, r18; high

; *******************************************************************************
; A subprogram of addition of value of intermediate frequency " 500 KHz "
;
; ldi r18, $00 	; In rightmost tens Hz are displayed at period
; ldi r19, $00 	; scores in 0.1 second. 500 KHz = 50000 = C350h
; ldi r20, $C3
; ldi r21, $50
;        
; add fm4, r21; low
; adc fm3, r20
; adc fm2, r19
; adc fm1, r18; higt

; *******************************************************************************
; the PROGRAM of translation 16h-> 10
;
; The initial number xxxxxxxxh fm1, fm2, fm3, fm4
; The divider r18, r19, r20, r21
; The answer r25
; Workers r15, r17, r22, r23
      
         clr r23	; the Register of converting
         ldi r18, $3B	;:1 000 000 000=3B 9A CA 00
         ldi r19, $9A
         ldi r20, $CA
         ldi r21, $00
	 rcall delen
	 mov r0, r25 	; in R0 the data for the discharge #0
              
         ldi r18, $05	; 1 discharge
         ldi r19, $F5 	;:100 000 000=05 F5 E1 00
         ldi r20, $E1
         rcall delen
         mov r1, r25 	; in R1 the data for the discharge #1
                
         ldi r18, $00	; 2 discharge
         ldi r19, $98 	;:10 000 000=00 98 96 80
         ldi r20, $96
         ldi r21, $80
         rcall delen
         mov r2, r25 	; in R2 the data for the discharge #2
                    
         ldi r18, $00	; 3 discharge
         ldi r19, $0F 	;:1 000 000=00 0F 42 40h
         ldi r20, $42
         ldi r21, $40
         rcall delen
         mov r3, r25 	; in R3 the data for the discharge #3
                
         ldi r19, $01	; 4 discharge
         ldi r20, $86 	;:100 000=00 01 86 A0h
         ldi r21, $A0
         rcall delen
         mov r4, r25 	; in R4 the data for the discharge #4
                        
         ldi r19, $00 	; 5 discharge
         ldi r20, $27	;:10 000=00 00 27 10h
         ldi r21, $10
         rcall delen
         mov r5, r25 	; in R5 the data for the discharge #5
                        
         ldi r20, $03	; 6 discharge
         ldi r21, $E8 	;:1 000=00 00 03 E8h
         rcall delen
         mov r6, r25 	; in R6 the data for the discharge #6
                      
         ldi r20, $00 	; 7 discharge
         ldi r21, $64	;:100=00 00 00 64h
         rcall delen
         mov r7, r25 	; in R7 the data for the discharge #7
         ldi r21, $0A	; 8 discharge
	 rcall delen 	;:10=00 00 00 0Ah
         mov r8, r25 	; in R8 the data for the discharge #8
                
         mov r9, fm4 	; 9 discharge; in R9 the data for the discharge #9
                
; *******************************************************************************
; Recording decoded 10 - in 7 segment values in registers R0-R9
	
	 ldi r19,0b10000000 	; the Code of a decimal point
	
	 mov r20, r0
	 rcall decoder
	 mov r0, r21
	
	 mov r20, r1
	 rcall decoder
	 mov r1, r21
	
	 mov r20, r2
	 rcall decoder
	 mov r2, r21
	
	 mov r20, r3
	 rcall decoder
	 mov r3, r21
	
	 mov r20, r4
	 rcall decoder
	 mov r4, r21
	
	 mov r20, r5
	 rcall decoder
	 mov r5, r21
	
	 mov r20, r6
	 rcall decoder
	 mov r6, r21
	
         mov r20, r7
	 rcall decoder
	 add r21, r19 	;Inclusion of a decimal point in 8 discharge
	 mov r7, r21
	
	 mov r20, r8
	 rcall decoder
	 mov r8, r21
	
	 mov r20, r9
	 rcall decoder
	 mov r9, r21
	
; *******************************************************************************
; A terminating connection to indication on 2 - the wire busbar (DATA, CK) 5 discharge
; Gauged frequency.
; In rightmost hundreds hertz of entry frequency are displayed.
; The point separates kilohertz.

; r8 - youngest registers containing 40 data bit for a terminating connection
; r7
; r6
; r5
; r4 - oldest

ldi r21, $8 	; the counter bits with decrement
read_byte1:
	 ror r8
	   
brcs C1 	; passage if C=1
brcc C0 	; passage if C=0

C1: 
	 sbi portb, 2 		; to output in a port In a data bit
	 rcall CK 		; to output in a port In clocking impulse
	 dec r21
	 brne read_byte1
	 rjmp A2 		; passage if the byte was completed; on 1, and the counter bits was unset
C0:
	 cbi portb, 2 		; to output in a port In a data bit
	 rcall CK 		; to output in a port In clocking impulse
	 dec r21
	 brne read_byte1

A2:
	 ldi r21, $8 	; the counter bits with decrement
read_byte2:
	 ror r7
	   
brcs C2_1 	; passage if C=1
brcc C2_0 	; passage if C=0

C2_1: 
	 sbi portb, 2 		; to output in a port In a data bit
	 rcall CK 		; to output in a port In clocking impulse
	 dec r21
	 brne read_byte2
	 rjmp A3 		; passage if the byte was completed; on 1, and the counter bits was unset
	
C2_0:
	 cbi portb, 2 		; to output in a port In a data bit
	 rcall CK 		; to output in a port In clocking impulse
	 dec r21
	 brne read_byte2
	
A3:
	 ldi r21, $8 	; the counter bits with decrement
read_byte3:
	 ror r6
	   
brcs C3_1 	; passage if C=1
brcc C3_0 	; passage if C=0

C3_1: 
	 sbi portb, 2 		; to output in a port In a data bit
	 rcall CK 		; to output in a port In clocking impulse
	 dec r21
	 brne read_byte3
	 rjmp A4 		; passage if the byte was completed; on 1, and the counter bits was unset
	
C3_0:
	 cbi portb, 2 		; to output in a port In a data bit
	 rcall CK 		; to output in a port In clocking impulse
	 dec r21
	 brne read_byte3
	
A4:
	 ldi r21, $8 	; the counter bits with decrement
read_byte4:
	 ror r5
	   
brcs C4_1 	; passage if C=1
brcc C4_0 	; passage if C=0

C4_1: 
	 sbi portb, 2 		; to output in a port In a data bit
	 rcall CK 		; to output in a port In clocking impulse
	 dec r21
	 brne read_byte4
	 rjmp A5 		; passage if the byte was completed; on 1, and the counter bits was unset
	
C4_0:
	 cbi portb, 2 		; to output in a port In a data bit
	 rcall CK 		; to output in a port In clocking impulse
	 dec r21
	brne read_byte4
	
A5:
	 ldi r21, $8 	; the counter bits with decrement
read_byte5:
	 ror r4
	   
brcs C5_1 	; passage if C=1
brcc C5_0 	; passage if C=0

C5_1: 
	 sbi portb, 2 		; to output in a port In a data bit
	 rcall CK 		; to output in a port In clocking impulse
	 dec r21
	 brne read_byte5
	rjmp all_leds 		; passage if the byte was completed; on 1, and the counter bits was unset
	
C5_0:
	 cbi portb, 2 		; to output in a port In a data bit
	 rcall CK 		; to output in a port In clocking impulse
	 dec r21
	 brne read_byte5
	
all_leds:
	 wdr 			; To reset the sentry timer
	 rjmp main_program 	; Repetition of cycle of the score with simultaneous indication
	
; ******************************************************************************
; A division subroutine
delen: ldi r25,-1
SUBii: inc r25
         sub fm4, r21	; low
         sbc fm3, r20
         sbc fm2, r19
         sbc fm1, r18	; high
         brsh SUBi1	; Passage if > 0
         add fm4, r21	; low
         adc fm3, r20
         adc fm2, r19
         adc fm1, r18	; high
ret
SUBi1: 
        ldi r23, $FF
        rjmp SUBii
                
; *******************************************************************************
; A subprogram of decoding of 10 values in 7 segment
;
; __ hgfedcba - segments
; 0b00000000 - bits in the register
;
decoder:   
	cpi r20,0x00
		breq SA
	cpi r20,0x01
         	breq S1
	cpi r20,0x02
         	breq S2
	cpi r20,0x03
         	breq S3
	cpi r20,0x04
        	 breq S4
	cpi r20,0x05
         	breq S5
	cpi r20,0x06
         	breq S6
	cpi r20,0x07
         	breq S7
	cpi r20,0x08
         	breq S8
	cpi r20,0x09
         	breq S9
                
S1: ldi r21,0b11111001 	; Digit " 1 " - the inverted values 	 
	 rjmp DD
S2: ldi r21,0b10100100 	; Digit " 2 " 	
         rjmp DD
S3: ldi r21,0b10110000 	; Digit " 3 " 	
         rjmp DD
S4: ldi r21,0b10011001 	; Digit " 4 " 	
         rjmp DD
S5: ldi r21,0b10010010 	; Digit " 5 " 	
         rjmp DD
S6: ldi r21,0b10000010 	; Digit " 6 " 	
         rjmp DD
S7: ldi r21,0b11111000 	; Digit " 7 " 	
         rjmp DD
S8: ldi r21,0b10000000 	; Digit " 8 "
         rjmp DD
S9: ldi r21,0b10010000 	; Digit " 9 "
         rjmp DD
SA: ldi r21,0b11000000 	; Digit " 0 "
DD:
	 ret
	 
; ********************************************************************************
; A subprogram clocking impulse

CK:
	 sbi portb, 1 		; to output in a port In clocking impulse
	 nop
	 nop
	 nop
	 nop
	 nop
	 nop
	 cbi portb, 1
ret

;********************************************************************************
;The program of a frequency meter - digital dial up to 4,5 MHz;
;Additional service functions are not realized, 
;intermediate frequency is programmed at wearing the processor.
;It is corrected and organized 04 April 2004.
;********************************************************************************