FIBn - PS8 - Computing & Engineering
FIBn
DEC > PDP8 > PAL8 Examples
As part of a TNMOC challenge, we have several machines (in fact one from each decade since 1950) running a similar task. That is generating the Fibonacci sequence. Below is my PDP8 / PAL8 assembly language version. This generates 100 lines, and is output to an ASR33 - to keep with the appropriate vintage!1 0020 *20
2 0100 BSIZE=100
3 /
4 00020 0525 FBUF, FBUFF
5 00021 0514 CLB, CCLB
6 00022 0417 PRT, PRNT
7 00023 0314 MCPY, MCOPY
8 00024 0500 PRP, RP
9 00025 0300 PMBP, MBP
10 /
11 00026 7777 KM1, 0-1 / -1d
12 00027 7766 KM10, 0-12 / -10d
13 00030 7700 KMB, 0-BSIZE
14 00031 0077 KPB, BSIZE-1
15 /
16 00032 0000 CARRY, 0
17 00033 7600 ILC, 0-200
18 00034 0000 LC, 0
19 00035 0000 CNT1, 0
20 /
21 00036 2000 PT1, T1
22 00037 0000 PT1A, 0
23 00040 2100 PT2, T2
24 00041 0000 PT2A, 0
25 00042 2200 PT3, T3
26 00043 0000 PT3A, 0
27 /
28 0200 *200
29 /// ENTRY POINT ///
30 00200 4421 ST, JMS I CLB / SET UP PTRS TO BUFFERS
31 00201 4420 JMS I FBUF / FILL BUFFERS WITH -1
32 00202 4425 JMS I PMBP / RESET POINTERS
33 /
34 / SET STARTING CONDITIONS
35 /
36 00203 7300 CLA CLL
37 00204 3437 DCA I PT1A / 0 IN LSD OF T1
38 00205 7001 IAC
39 00206 3441 DCA I PT2A / 1 IN LSD OF T2
40 /
41 / SET LINES COUNT
42 00207 1033 TAD ILC
43 00210 3034 DCA LC
44 /
45 / CLEAR PENDING CARRY
46 00211 7300 CLA CLL
47 00212 3032 DCA CARRY
48 /
49 / ADD THE TWO VALUES POINTED TO IN FIRST TWO BUFFERS
50 00213 4421 CL2, JMS I CLB
51 00214 4424 JMS I PRP
52 00215 7300 CLA CLL
53 00216 1030 TAD KMB / -BSIZE
54 00217 3035 DCA CNT1
55 /
56 00220 7300 CL3, CLA CLL
57 00221 1032 TAD CARRY
58 00222 1437 TAD I PT1A / EG 8 / 5 / 2
59 00223 1441 TAD I PT2A / EG 4 / 5 / 3
60 00224 1027 TAD KM10 / 8+4-10=2 / 5+5-10=0 / 2+3-10=-5
61 00225 7500 SMA / SKIP IF A < 0 - IE NO CARRY OCCURRED
62 00226 5240 JMP C
63 00227 5230 JMP NC
64 /
65 00230 7300 NC, CLA CLL / 0
66 00231 1032 TAD CARRY
67 00232 1437 TAD I PT1A / 2
68 00233 1441 TAD I PT2A / 3
69 00234 3443 DCA I PT3A / 5
70 00235 7300 CLA CLL
71 00236 3032 DCA CARRY / CLR CARRY
72 00237 5250 JMP D
73 /
74 00240 7300 C, CLA CLL
75 00241 1032 TAD CARRY
76 00242 1437 TAD I PT1A / 8
77 00243 1441 TAD I PT2A / 4
78 00244 1027 TAD KM10 / 10
79 00245 3443 DCA I PT3A / 2
80 00246 7301 CLA CLL IAC
81 00247 3032 DCA CARRY / AND SET CARRY
82 /
83 00250 2035 D, ISZ CNT1 /NXT COL
84 00251 7410 SKP
85 00252 5255 JMP P
86 /
87 00253 4425 JMS I PMBP // MOVE BUFFER POINTERS
88 00254 5220 JMP CL3
89 /
90 / PRINT T3
91 00255 4422 P, JMS I PRT
92 00256 2200 T3
93 /
94 / COPY T2 TO T1, AND T3 TO T2
95 00257 4423 JMS I MCPY
96 00260 2100 T2
97 00261 2000 T1
98 00262 7700 0-BSIZE
99 00263 4423 JMS I MCPY
100 00264 2200 T3
101 00265 2100 T2
102 00266 7700 0-BSIZE
103 /
104 / CHECK COUNT AND POTENTIALLY ROUND AGAIN
105 00267 2034 ISZ LC
106 00270 7410 SKP
107 00271 7402 HLT // ALL DONE
108 /
109 00272 5213 JMP CL2
110 /
111 0300 *300
112 00300 7000 MBP, NOP / MOVE BUFFER PTRS BACK ONE
113 00301 7300 CLA CLL
114 00302 1037 TAD PT1A
115 00303 1026 TAD KM1
116 00304 3037 DCA PT1A
117 00305 1041 TAD PT2A
118 00306 1026 TAD KM1
119 00307 3041 DCA PT2A
120 00310 1043 TAD PT3A
121 00311 1026 TAD KM1
122 00312 3043 DCA PT3A
123 00313 5700 JMP I MBP
124 00314 7000 MCOPY, NOP / COPY P3 WORDS FROM P1 TO P2
125 00315 7300 CLA CLL
126 00316 1714 TAD I MCOPY
127 00317 3340 DCA MT1
128 00320 2314 ISZ MCOPY
129 00321 1714 TAD I MCOPY
130 00322 3341 DCA MT2
131 00323 2314 ISZ MCOPY
132 00324 1714 TAD I MCOPY
133 00325 3342 DCA MT3
134 00326 2314 ISZ MCOPY
135 00327 1342 TAD MT3
136 00330 3343 DCA MTCNT
137 00331 1740 MCPY1, TAD I MT1
138 00332 3741 DCA I MT2
139 00333 2340 ISZ MT1
140 00334 2341 ISZ MT2
141 00335 2343 ISZ MTCNT
142 00336 5331 JMP MCPY1
143 00337 5714 JMP I MCOPY
144 00340 7000 MT1, NOP
145 00341 7000 MT2, NOP
146 00342 7000 MT3, NOP
147 00343 7000 MTCNT, NOP
148 /
149 0400 *400
150 00400 0000 CRLF, 0 / PRINT NEWLINE
151 00401 7300 CLA CLL
152 00402 1207 TAD K215
153 00403 4211 JMS TYPE
154 00404 1210 TAD K212
155 00405 4211 JMS TYPE
156 00406 5600 JMP I CRLF
157 00407 0015 K215, 15
158 00410 0012 K212, 12
159 /
160 00411 0000 TYPE, 0 / PRINT THE ASCII CHARACTER IN ACC
161 00412 6046 TLS
162 00413 6041 TSF
163 00414 5213 JMP .-1
164 00415 7300 CLA CLL
165 00416 5611 JMP I TYPE
166 /
167 00417 7000 PRNT, NOP / PRINT BUFFER
168 00420 7300 CLA CLL
169 00421 1617 TAD I PRNT / GET ADDR OF START OF BUFFER
170 00422 3253 DCA PPTR
171 00423 2217 ISZ PRNT / FIX RETURN ADDR
172 00424 1030 TAD KMB / SETUP COUNT OF CHARS
173 00425 3252 DCA PCNT
174 00426 3254 DCA LZ
175 /
176 00427 7300 PRNT1, CLA CLL
177 00430 1653 TAD I PPTR / GET CHAR
178 00431 7440 SZA / IS IT ZERO?
179 00432 5237 JMP NZ / NO
180 00433 7300 CLA CLL / YES
181 00434 1254 TAD LZ / IS LZ SET
182 00435 7450 SNA
183 00436 5245 JMP NOK
184 00437 7300 NZ, CLA CLL
185 00440 1653 TAD I PPTR
186 00441 1255 TAD K260 / ASCII'FY
187 00442 4211 JMS TYPE / PRINT IT
188 00443 7201 CLA IAC
189 00444 3254 DCA LZ
190 /
191 00445 2253 NOK, ISZ PPTR / NEXT CHAR
192 00446 2252 ISZ PCNT / DONE YET?
193 00447 5227 JMP PRNT1 / NO, ROUND AGAIN
194 00450 4200 JMS CRLF / YES, NEW LINE
195 00451 5617 JMP I PRNT / DONE
196 00452 0000 PCNT, 0
197 00453 0000 PPTR, 0
198 00454 0000 LZ, 0
199 00455 0260 K260, 260
200 /
201 0500 *500 / RESET POINTERS
202 00500 7000 RP, NOP
203 00501 7300 CLA CLL
204 00502 1037 TAD PT1A
205 00503 1031 TAD KPB
206 00504 3037 DCA PT1A
207 00505 1041 TAD PT2A
208 00506 1031 TAD KPB
209 00507 3041 DCA PT2A
210 00510 1043 TAD PT3A
211 00511 1031 TAD KPB
212 00512 3043 DCA PT3A
213 00513 5700 JMP I RP
214 /
215 00514 7000 CCLB, NOP / SET UP PTRS TO THREE BUFFERS
216 00515 7300 CLA CLL
217 00516 1036 TAD PT1
218 00517 3037 DCA PT1A
219 00520 1040 TAD PT2
220 00521 3041 DCA PT2A
221 00522 1042 TAD PT3
222 00523 3043 DCA PT3A
223 00524 5714 JMP I CCLB
224 /
225 00525 7000 FBUFF, NOP / FILL ALL BUFFERS WITH 0
226 00526 7300 CLA CLL
227 00527 1030 TAD KMB
228 00530 3342 DCA FCNT
229 00531 3437 CL1, DCA I PT1A
230 00532 2037 ISZ PT1A
231 00533 3441 DCA I PT2A
232 00534 2041 ISZ PT2A
233 00535 3443 DCA I PT3A
234 00536 2043 ISZ PT3A
235 00537 2342 ISZ FCNT // ALL DONE?
236 00540 5331 JMP CL1 // NO
237 00541 5725 JMP I FBUFF // YES, RETURN
238 00542 7000 FCNT, NOP
239 /
240 2000 *2000
241 02000 0000 T1, 0
242 2100 *2100
243 02100 0000 T2, 0
244 2200 *2200
245 02200 0000 T3, 0
246 $
No detected errors
No links generated
