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[/] [RISCMCU/] [trunk/] [asm/] [simple_calculator.asm] - Blame information for rev 28

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.include "riscmcu.inc"
 
.def    key = r16
.def    temp = r17
.def    B = r18
.def    C = r19
.def    addsub = r24
.def    counter = r25
.def    tcount = r26
.def    led = r27
 
.cseg
        rjmp    reset
        rjmp    extint
        rjmp    timer
 
extint:
        clr     B
        clr     C
        clr     addsub
        out     portb,c
        reti
 
timer:
        in      temp,sreg
        inc     tcount
        cpi     tcount,24
        brne    tback
        clr     tcount
        cpi     led,0b10000
        brne    t4
        ldi     led,0b0001
t4:     com     led
        out     portc,led
        com     led
        lsl     led
        out     sreg,temp
tback:  reti
 
 
reset:
 
        clr     B
        clr     C
        clr     addsub
        ldi     counter,3
        ldi     led,0b0001
 
        ldi     temp,0b11110000
        out     ddrd,temp
        ser     temp
        out     ddrb,temp       ; PORT B as output
        out     ddrc,temp       ; PORT C as output
        out     portc,temp      ; PORT C leds OFF
        out     portd,temp      ; PORT D output HI
        out     gimsk,temp      ; Enable external interrupt
        out     timsk,temp      ; Enable Timer interrupt
        ldi     temp,5
        out     tccr0,temp      ; timer clock source = divide by 1024
 
        rcall   ldtable
        sei
 
;*************************************************
; Detect Keys
 
rescan: rcall   sdelay
 
        sbi     portd,6
        cbi     portd,4
        ldi     zp,table
        in      key,pind
        cbr     key,$F0
        cpi     key,$0F
        brne    press
 
        sbi     portd,4
        cbi     portd,5
        ldi     zp,table+1
        in      key,pind
        cbr     key,$F0
        cpi     key,$0F
        brne    press
 
        sbi     portd,5
        cbi     portd,6
        ldi     zp,table+2
        in      key,pind
        cbr     key,$F0
        cpi     key,$0F
        brne    press
 
        rjmp    rescan
 
press:
        rcall   sdelay
        in      temp,pind
        cbr     temp,$F0
        cpse    key,temp
        rjmp    rescan
        sbrs    key,1
        subi    zp,-3
        sbrs    key,2
        subi    zp,-6
        sbrs    key,3
        subi    zp,-9
        ld      key,Z
 
;*************************************************
; Operation
 
        cpi     key,$A
        breq    addkey
        cpi     key,$B
        breq    subkey
 
        swap    B
        cbr     B,$0f
        add     B,key
        out     portb,B
 
        rjmp    holding
 
addkey:
        cbr     addsub,$01
        rjmp    arith
 
subkey:
        sbr     addsub,$01
 
arith:
        swap    addsub
        sbrc    addsub,0
        rjmp    subf
        rcall   BCDadd
        out     portb,C
        rcall   overflow
        clr     B
        rjmp    holding
 
subf:
        rcall   BCDsub
        out     portb,C
        rcall   overflow
        clr     B
        rjmp    holding
 
;*************************************************
; Key press released ?
 
holding:
        rcall   sdelay
        in      key,pind
        cbr     key,$F0
        ldi     temp,$0F
        cpse    key,temp
        rjmp    holding
        rjmp    rescan
 
;*************************************************
; overflow ?
 
overflow:
        sbrs    b,0
        ret
        cli
        sbi     ddrd,7
        cbi     portd,7
        rcall   delay
        sbi     portd,7
        cbi     ddrd,7
        sei
        ret
 
;*************************************************
; Short Delay
 
sdelay:
        clr     temp
s10:    dec     temp
        brne    s10
        ret
 
;*************************************************
; Load Table
 
ldtable:
        ldi     ZP,table
        ldi     temp,1
        st      Z+,temp
        ldi     temp,2
        st      Z+,temp
        ldi     temp,3
        st      Z+,temp
        ldi     temp,4
        st      Z+,temp
        ldi     temp,5
        st      Z+,temp
        ldi     temp,6
        st      Z+,temp
        ldi     temp,7
        st      Z+,temp
        ldi     temp,8
        st      Z+,temp
        ldi     temp,9
        st      Z+,temp
        ldi     temp,$B
        st      Z+,temp
        ldi     temp,0
        st      Z+,temp
        ldi     temp,$A
        st      Z+,temp
        ret
 
;*******************************************
delay:
del:    ldi     ZP,count
        ld      temp,Z
        dec     temp
        st      Z,temp
        brne    del
        ldi     ZP,count+1
        ld      temp,Z
        dec     temp
        st      Z,temp
        brne    del
        dec     counter
        brne    del
        ldi     counter,3
        ret
 
;***** Subroutine Register Variables
 
.def    BCD1    =r19            ;BCD input value #1
.def    BCD2    =r18            ;BCD input value #2
.def    tmpadd  =r16            ;temporary register
 
;***** Code
 
BCDadd:
        ldi     tmpadd,6        ;value to be added later
        add     BCD1,BCD2       ;add the numbers binary
        clr     BCD2            ;clear BCD carry
        brcc    add_0           ;if carry not clear
        ldi     BCD2,1          ;    set BCD carry
add_0:  brhs    add_1           ;if half carry not set
        add     BCD1,tmpadd     ;    add 6 to LSD
        brhs    add_2           ;    if half carry not set (LSD <= 9)
        subi    BCD1,6          ;        restore value
        rjmp    add_2           ;else
add_1:  add     BCD1,tmpadd     ;    add 6 to LSD
add_2:  swap    tmpadd
        add     BCD1,tmpadd     ;add 6 to MSD
        brcs    add_4           ;if carry not set (MSD <= 9)
        sbrs    BCD2,0          ;    if previous carry not set
        subi    BCD1,$60        ;       restore value
add_3:  ret                     ;else
add_4:  ldi     BCD2,1          ;    set BCD carry
        ret
 
 
;***** Subroutine Register Variables
 
.def    BCDa    =r19            ;BCD input value #1
.def    BCDb    =r18            ;BCD input value #2
 
;***** Code
 
BCDsub:
        sub     BCDa,BCDb       ;subtract the numbers binary
        clr     BCDb
        brcc    sub_0           ;if carry not clear
        ldi     BCDb,1          ;    store carry in BCDB1, bit 0
sub_0:  brhc    sub_1           ;if half carry not clear
        subi    BCDa,$06        ;    LSD = LSD - 6
sub_1:  sbrs    BCDb,0          ;if previous carry not set
        ret                     ;    return
        subi    BCDa,$60        ;subtract 6 from MSD
        ldi     BCDb,1          ;set underflow carry
        brcc    sub_2           ;if carry not clear
        ldi     BCDb,1          ;    clear underflow carry
sub_2:  ret
 
 
 
 
.dseg
table:  .byte   12
count:  .byte   2

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[/] [RISCMCU/] [trunk/] [asm/] [simple_calculator.asm] - Blame information for rev 28

Line No.	Rev	Author	Line
1	9	yapzihe	`.include "riscmcu.inc"`
2
3			`.def key = r16`
4			`.def temp = r17`
5			`.def B = r18`
6			`.def C = r19`
7			`.def addsub = r24`
8			`.def counter = r25`
9			`.def tcount = r26`
10			`.def led = r27`
11
12			`.cseg`
13			`rjmp reset`
14			`rjmp extint`
15			`rjmp timer`
16
17			`extint:`
18			`clr B`
19			`clr C`
20			`clr addsub`
21			`out portb,c`
22			`reti`
23
24			`timer:`
25			`in temp,sreg`
26			`inc tcount`
27			`cpi tcount,24`
28			`brne tback`
29			`clr tcount`
30			`cpi led,0b10000`
31			`brne t4`
32			`ldi led,0b0001`
33			`t4: com led`
34			`out portc,led`
35			`com led`
36			`lsl led`
37			`out sreg,temp`
38			`tback: reti`
39
40
41			`reset:`
42
43			`clr B`
44			`clr C`
45			`clr addsub`
46			`ldi counter,3`
47			`ldi led,0b0001`
48
49			`ldi temp,0b11110000`
50			`out ddrd,temp`
51			`ser temp`
52			`out ddrb,temp ; PORT B as output`
53			`out ddrc,temp ; PORT C as output`
54			`out portc,temp ; PORT C leds OFF`
55			`out portd,temp ; PORT D output HI`
56			`out gimsk,temp ; Enable external interrupt`
57			`out timsk,temp ; Enable Timer interrupt`
58			`ldi temp,5`
59			`out tccr0,temp ; timer clock source = divide by 1024`
60
61			`rcall ldtable`
62			`sei`
63
64			`;*************************************************`
65			`; Detect Keys`
66
67			`rescan: rcall sdelay`
68
69			`sbi portd,6`
70			`cbi portd,4`
71			`ldi zp,table`
72			`in key,pind`
73			`cbr key,$F0`
74			`cpi key,$0F`
75			`brne press`
76
77			`sbi portd,4`
78			`cbi portd,5`
79			`ldi zp,table+1`
80			`in key,pind`
81			`cbr key,$F0`
82			`cpi key,$0F`
83			`brne press`
84
85			`sbi portd,5`
86			`cbi portd,6`
87			`ldi zp,table+2`
88			`in key,pind`
89			`cbr key,$F0`
90			`cpi key,$0F`
91			`brne press`
92
93			`rjmp rescan`
94
95			`press:`
96			`rcall sdelay`
97			`in temp,pind`
98			`cbr temp,$F0`
99			`cpse key,temp`
100			`rjmp rescan`
101			`sbrs key,1`
102			`subi zp,-3`
103			`sbrs key,2`
104			`subi zp,-6`
105			`sbrs key,3`
106			`subi zp,-9`
107			`ld key,Z`
108
109			`;*************************************************`
110			`; Operation`
111
112			`cpi key,$A`
113			`breq addkey`
114			`cpi key,$B`
115			`breq subkey`
116
117			`swap B`
118			`cbr B,$0f`
119			`add B,key`
120			`out portb,B`
121
122			`rjmp holding`
123
124			`addkey:`
125			`cbr addsub,$01`
126			`rjmp arith`
127
128			`subkey:`
129			`sbr addsub,$01`
130
131			`arith:`
132			`swap addsub`
133			`sbrc addsub,0`
134			`rjmp subf`
135			`rcall BCDadd`
136			`out portb,C`
137			`rcall overflow`
138			`clr B`
139			`rjmp holding`
140
141			`subf:`
142			`rcall BCDsub`
143			`out portb,C`
144			`rcall overflow`
145			`clr B`
146			`rjmp holding`
147
148			`;*************************************************`
149			`; Key press released ?`
150
151			`holding:`
152			`rcall sdelay`
153			`in key,pind`
154			`cbr key,$F0`
155			`ldi temp,$0F`
156			`cpse key,temp`
157			`rjmp holding`
158			`rjmp rescan`
159
160			`;*************************************************`
161			`; overflow ?`
162
163			`overflow:`
164			`sbrs b,0`
165			`ret`
166			`cli`
167			`sbi ddrd,7`
168			`cbi portd,7`
169			`rcall delay`
170			`sbi portd,7`
171			`cbi ddrd,7`
172			`sei`
173			`ret`
174
175			`;*************************************************`
176			`; Short Delay`
177
178			`sdelay:`
179			`clr temp`
180			`s10: dec temp`
181			`brne s10`
182			`ret`
183
184			`;*************************************************`
185			`; Load Table`
186
187			`ldtable:`
188			`ldi ZP,table`
189			`ldi temp,1`
190			`st Z+,temp`
191			`ldi temp,2`
192			`st Z+,temp`
193			`ldi temp,3`
194			`st Z+,temp`
195			`ldi temp,4`
196			`st Z+,temp`
197			`ldi temp,5`
198			`st Z+,temp`
199			`ldi temp,6`
200			`st Z+,temp`
201			`ldi temp,7`
202			`st Z+,temp`
203			`ldi temp,8`
204			`st Z+,temp`
205			`ldi temp,9`
206			`st Z+,temp`
207			`ldi temp,$B`
208			`st Z+,temp`
209			`ldi temp,0`
210			`st Z+,temp`
211			`ldi temp,$A`
212			`st Z+,temp`
213			`ret`
214
215			`;*******************************************`
216			`delay:`
217			`del: ldi ZP,count`
218			`ld temp,Z`
219			`dec temp`
220			`st Z,temp`
221			`brne del`
222			`ldi ZP,count+1`
223			`ld temp,Z`
224			`dec temp`
225			`st Z,temp`
226			`brne del`
227			`dec counter`
228			`brne del`
229			`ldi counter,3`
230			`ret`
231
232			`;***** Subroutine Register Variables`
233
234			`.def BCD1 =r19 ;BCD input value #1`
235			`.def BCD2 =r18 ;BCD input value #2`
236			`.def tmpadd =r16 ;temporary register`
237
238			`;***** Code`
239
240			`BCDadd:`
241			`ldi tmpadd,6 ;value to be added later`
242			`add BCD1,BCD2 ;add the numbers binary`
243			`clr BCD2 ;clear BCD carry`
244			`brcc add_0 ;if carry not clear`
245			`ldi BCD2,1 ; set BCD carry`
246			`add_0: brhs add_1 ;if half carry not set`
247			`add BCD1,tmpadd ; add 6 to LSD`
248			`brhs add_2 ; if half carry not set (LSD <= 9)`
249			`subi BCD1,6 ; restore value`
250			`rjmp add_2 ;else`
251			`add_1: add BCD1,tmpadd ; add 6 to LSD`
252			`add_2: swap tmpadd`
253			`add BCD1,tmpadd ;add 6 to MSD`
254			`brcs add_4 ;if carry not set (MSD <= 9)`
255			`sbrs BCD2,0 ; if previous carry not set`
256			`subi BCD1,$60 ; restore value`
257			`add_3: ret ;else`
258			`add_4: ldi BCD2,1 ; set BCD carry`
259			`ret`
260
261
262			`;***** Subroutine Register Variables`
263
264			`.def BCDa =r19 ;BCD input value #1`
265			`.def BCDb =r18 ;BCD input value #2`
266
267			`;***** Code`
268
269			`BCDsub:`
270			`sub BCDa,BCDb ;subtract the numbers binary`
271			`clr BCDb`
272			`brcc sub_0 ;if carry not clear`
273			`ldi BCDb,1 ; store carry in BCDB1, bit 0`
274			`sub_0: brhc sub_1 ;if half carry not clear`
275			`subi BCDa,$06 ; LSD = LSD - 6`
276			`sub_1: sbrs BCDb,0 ;if previous carry not set`
277			`ret ; return`
278			`subi BCDa,$60 ;subtract 6 from MSD`
279			`ldi BCDb,1 ;set underflow carry`
280			`brcc sub_2 ;if carry not clear`
281			`ldi BCDb,1 ; clear underflow carry`
282			`sub_2: ret`
283
284
285
286
287			`.dseg`
288			`table: .byte 12`
289			`count: .byte 2`