/
flow1.s
324 lines (310 loc) · 6.75 KB
/
flow1.s
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
.segment "CODE"
; ----------------------------------------------------------------------------
; "FOR" STATEMENT
;
; FOR PUSHES 18 BYTES ON THE STACK:
; 2 -- TXTPTR
; 2 -- LINE NUMBER
; 5 -- INITIAL (CURRENT) FOR VARIABLE VALUE
; 1 -- STEP SIGN
; 5 -- STEP VALUE
; 2 -- ADDRESS OF FOR VARIABLE IN VARTAB
; 1 -- FOR TOKEN ($81)
; ----------------------------------------------------------------------------
FOR:
lda #$80
sta SUBFLG
jsr LET
jsr GTFORPNT
bne L2619
txa
adc #FOR_STACK1
tax
txs
L2619:
pla
pla
lda #FOR_STACK2
jsr CHKMEM
jsr DATAN
clc
tya
adc TXTPTR
pha
lda TXTPTR+1
adc #$00
pha
lda CURLIN+1
pha
lda CURLIN
pha
lda #TOKEN_TO
jsr SYNCHR
jsr CHKNUM
jsr FRMNUM
lda FACSIGN
ora #$7F
and FAC+1
sta FAC+1
lda #<STEP
ldy #>STEP
sta INDEX
sty INDEX+1
jmp FRM_STACK3
; ----------------------------------------------------------------------------
; "STEP" PHRASE OF "FOR" STATEMENT
; ----------------------------------------------------------------------------
STEP:
lda #<CON_ONE
ldy #>CON_ONE
jsr LOAD_FAC_FROM_YA
jsr CHRGOT
cmp #TOKEN_STEP
bne L2665
jsr CHRGET
jsr FRMNUM
L2665:
jsr SIGN
jsr FRM_STACK2
lda FORPNT+1
pha
lda FORPNT
pha
lda #$81
pha
; ----------------------------------------------------------------------------
; PERFORM NEXT STATEMENT
; ----------------------------------------------------------------------------
NEWSTT:
jsr ISCNTC
lda TXTPTR
ldy TXTPTR+1
.if .def(CONFIG_NO_INPUTBUFFER_ZP) && .def(CONFIG_2)
cpy #>INPUTBUFFER
.ifdef CBM2
nop
.endif
beq LC6D4
.else
; BUG on AppleSoft I,
; fixed differently on AppleSoft II (ldx/inx)
beq L2683
.endif
sta OLDTEXT
sty OLDTEXT+1
LC6D4:
ldy #$00
L2683:
lda (TXTPTR),y
.ifndef CONFIG_11
beq LA5DC ; old: 1 cycle more on generic case
cmp #$3A
beq NEWSTT2
SYNERR1:
jmp SYNERR
LA5DC:
.else
bne COLON; new: 1 cycle more on ":" case
.endif
ldy #$02
lda (TXTPTR),y
clc
.ifdef CONFIG_2
jeq L2701
.else
beq L2701
.endif
iny
lda (TXTPTR),y
sta CURLIN
iny
lda (TXTPTR),y
sta CURLIN+1
tya
adc TXTPTR
sta TXTPTR
bcc NEWSTT2
inc TXTPTR+1
NEWSTT2:
jsr CHRGET
jsr EXECUTE_STATEMENT
jmp NEWSTT
; ----------------------------------------------------------------------------
; EXECUTE A STATEMENT
;
; (A) IS FIRST CHAR OF STATEMENT
; CARRY IS SET
; ----------------------------------------------------------------------------
EXECUTE_STATEMENT:
.ifndef CONFIG_11A
beq RET1
.else
beq RET2
.endif
.ifndef CONFIG_11
sec
.endif
EXECUTE_STATEMENT1:
sbc #$80
.ifndef CONFIG_11
jcc LET ; old: 1 cycle more on instr.
.else
bcc LET1; new: 1 cycle more on assignment
.endif
cmp #NUM_TOKENS
.ifdef CONFIG_2
bcs LC721
.else
bcs SYNERR1
.endif
asl a
tay
lda TOKEN_ADDRESS_TABLE+1,y
pha
lda TOKEN_ADDRESS_TABLE,y
pha
jmp CHRGET
.ifdef CONFIG_11
LET1:
jmp LET
COLON:
cmp #$3A
beq NEWSTT2
SYNERR1:
jmp SYNERR
.endif
.ifdef CONFIG_2; GO TO
LC721:
cmp #TOKEN_GO-$80
bne SYNERR1
jsr CHRGET
lda #TOKEN_TO
jsr SYNCHR
jmp GOTO
.endif
; ----------------------------------------------------------------------------
; "RESTORE" STATEMENT
; ----------------------------------------------------------------------------
RESTORE:
sec
lda TXTTAB
sbc #$01
ldy TXTTAB+1
bcs SETDA
dey
SETDA:
sta DATPTR
sty DATPTR+1
RET2:
rts
.include "iscntc.s"
;!!! runs into "STOP"
; ----------------------------------------------------------------------------
; "STOP" STATEMENT
; ----------------------------------------------------------------------------
STOP:
bcs END2
; ----------------------------------------------------------------------------
; "END" STATEMENT
; ----------------------------------------------------------------------------
END:
clc
END2:
bne RET1
lda TXTPTR
ldy TXTPTR+1
.if .def(CONFIG_NO_INPUTBUFFER_ZP) && .def(CONFIG_2)
; BUG on AppleSoft I
; fix exists on AppleSoft II
; TXTPTR+1 will always be > 0
ldx CURLIN+1
inx
.endif
beq END4
sta OLDTEXT
sty OLDTEXT+1
CONTROL_C_TYPED:
lda CURLIN
ldy CURLIN+1
sta OLDLIN
sty OLDLIN+1
END4:
pla
pla
L2701:
lda #<QT_BREAK
ldy #>QT_BREAK
.ifndef KBD
ldx #$00
stx Z14
.endif
bcc L270E
jmp PRINT_ERROR_LINNUM
L270E:
jmp RESTART
.ifdef KBD
LE664:
tay
jmp SNGFLT
.endif
; ----------------------------------------------------------------------------
; "CONT" COMMAND
; ----------------------------------------------------------------------------
CONT:
bne RET1
ldx #ERR_CANTCONT
ldy OLDTEXT+1
bne L271C
jmp ERROR
L271C:
lda OLDTEXT
sta TXTPTR
sty TXTPTR+1
lda OLDLIN
ldy OLDLIN+1
sta CURLIN
sty CURLIN+1
RET1:
rts
.ifdef KBD
PRT:
jsr GETBYT
txa
; not ROR bug safe
ror a
ror a
ror a
sta $8F
rts
LE68C:
ldy #$12
LE68E:
lda LEA30,y
sta $03A2,y
dey
bpl LE68E
rts
.endif
.ifndef AIM65
.if .def(CONFIG_NULL) || .def(CONFIG_PRINTNULLS)
; CBM1 has the keyword removed,
; but the code is still here
NULL:
jsr GETBYT
bne RET1
inx
cpx #NULL_MAX
bcs L2739
dex
stx Z15
L2738:
rts
L2739:
jmp IQERR
.endif
.ifndef CONFIG_11A
CLEAR:
bne RET1
jmp CLEARC
.endif
.endif