1 / TD8E Dectape RESTORE Program
2 / This program will receive a DECtape image and write it to the tape. The
3 / tape is written, then it is reread to verify.
5 / The program (PC) sending the data should be started before this program
7 / See dump for the format of the serial data.
8 / To run start at 0200.
9 / SR 11 should be drive, only 0 and 1 supported without reassembling
10 / SR 6-8 should be maximum memory field in computer, needs 8k minimum
11 / Should halt at label FINISH (140) with AC = 0 if it worked, AC not equal to
12 / zero indicates checksum on read didn't match that of data received
13 / Hitting cont will restart the program if at normal end
15 / Number of retries is set to 1 for reading and writing.
17 / The current block being written to will be displayed in the AC
18 / while serial data is transfering.
20 / This program only will work with the resttd8e C program since it needs
21 / to hanshake transfers to prevent overrun on the serial data.
22 / The C program must be started first.
24 / This transfers the standard 129 word by 1474 blocks used by OS/8 etc.
25 / Other formats can be handled by changing constants below
27 INAD=400 / Address of serial input, 30 for console
35 OUTAD=410 / Address of serial output, 40 for console
43 /2 TD8E INITIALIZER PROGRAM, V7A
45 /COPYRIGHT (C) 1975, 1977
46 /DIGITAL EQUIPMENT CORPORATION, MAYNARD, MASS.
50 /THIS SOFTWARE IS FURNISHED UNDER A LICENSE FOR USE ONLY ON A
51 /SINGLE COMPUTER SYSTEM AND MAY BE COPIED ONLY WITH THE INCLU-
52 /SION OF THE ABOVE COPYRIGHT NOTICE. THIS SOFTWARE, OR ANT OTHER
53 /COPIES THEREOF, MAY NOT BR PROVIDED OR OTHERWISE MADE AVAILABLE
54 /TO ANY OTHER PERSON EXCEPT FOR USE ON SUCH SYSTEM AND TO ONE WHO
55 /AGREES TO THESE LICENSE TERMS. TITLE TO AND OWNERSHIP OF THE
56 /SOFTWARE SHALL AT ALL TIMES REMAIN IN DEC.
59 /THE INFORMATION IN THIS SOFTWARE IS SUBJECT TO CHANGE WITHOUT
60 /NOTICE AND SHOULD NOT BE CONSTRUED AS A COMMITMENT BY DIGITAL
61 /EQUIPMRNT COROPATION.
63 /DEC ASSUMES NO RESPONSIBILITY FOR THE USE OR RELIABILITY OF ITS
64 /SOFTWARE ON EQUIPMENT WHICH IS NOT SUPPLIED BY DEC.
72 /DECEMBER 21, 1973 GB/RL/EF/SR
75 / THE ROUTINE DESCRIBED AND LISTED HERE IS A GENERAL
76 /DATA HANDLER FOR THE TD8E DECTAPE SYSTEM. THE ROUTINE
77 /CONTAINS SEARCH, READ, AND WRITE FUNCTIONS IN A FORMAT
78 /WHICH IS COMPATIBLE WITH OS/8 DEVICE HANDLER CALLING
81 /FIXES SINCE FIELD-TEST RELEASE:
83 /1. FIXED BUG RE CLA ON RETRY AFTER ERROR
84 /2. ALLOWED FINAL BOOTSTRAP TO BE INTO A WRITE-LOCKED DEVICE
88 /3. FIXED BUG RE TD8E BUILD (V6B PATCH)
90 /THIS ROUTINE CAN BE RE-EDITED AND ASSEMBLED TO PRODUCE
91 /VARIATIONS ON THE BASIC TD8E SYSTEM. ASSEMBLY PARAMETERS
93 /A) WHAT DRIVES (UNITS 0-7) WILL BE USED
94 /B) THE ORIGIN OF THE TWO PAGE ROUTINE
95 /C) WHAT MEMORY FIELD THE ROUTINE WILL RUN IN
96 /D) THE SIZE OF THE DECTAPE BLOCK TO BE READ/WRITTEN
98 /FOLLOWING ARE THE PARAMETERS SET UP FOR THE STANDARD
99 /DEC VERSION OF THIS ROUTINE:
101 DRIVE=10 /UNITS 0 AND 1 SELECTED
102 ORIGIN=600 /ENTER AT ORIGIN, ORIGIN+4
103 AFIELD=0 /INITIAL FIELD SETTING
104 MFIELD=00 /AFIELD*10=MFIELD
105 WDSBLK=201 /129 WORDS PER BLOCK
107 /THE USE OF THE PARAMETERS IS AS FOLLOWS:
109 / DRIVE: DRIVE DETERMINES WHICH UNITS WILL BE SELECTED
110 / DRIVE=10 IMPLIES UNITS 0 &1
111 / DRIVE=20 IMPLIES UNITS 2&3
112 / DRIVE=30 IMPLIES UNITS 4&5
113 / DRIVE=40 IMPLIES UNITS 6&7
115 /ORIGIN: ALTERING ORIGIN CAUSES ASSEMBLY IN A DIFFERENT
116 / MEMORY LOCATION. WHEN CHANGING ORIGIN KEEP IN MIND
117 /THAT THIS IS A TWO PAGE ROUTINE.
119 /AFIELD: AFIELD DETERMINES THE INITIAL FIELD SETTING FOR THE
120 / LOADER. PERMISSIBLE VALUES FOR AFIELD ARE 0 TO 7.
122 /MFIELD: MFIELD IS USED IN A CIF CDF MFIELD INSTRUCTION.
123 / THE VALUE INSERTED FOR MFIELD SHOULD BE 10(8) TIMES
124 / THE VALUE FOR AFIELD. THE PERMISSIBLE VALUES ARE 00-70.
126 /WDSBLK: WDSBLK GOVERNS HOW MANY WORDS THE ROUTINE THINKS ARE
127 / IN A DECTAPE BLOCK. THE STANDARD VALUE IS 201(8) OR
128 / 128 DECIMAL. NOTE THAT THE FUNCTION WORD BIT 10 CAN
129 / 129 DECIMAL ??? (DJG)
130 / BE USED TO SUBTRACT ONE FROM WDSBLK. THE VALUE USED
131 / FOR WDSBLK SHOULD BE THE NUMBER OF WORDS THE TAPE WAS
132 / FORMATTED TO CONTAIN.
134 /IF WE WANT A HANDLER FOR UNITS 2&3 TO RESIDE IN
135 /FIELD 2 AT LOCATION 3000 AND READ/WRITE 256(10) WORDS
136 /PER BLOCK, THE PARAMETERS WOULD BE:
142 \f/THE CALL TO THE SUBROUTINE FOLLOWS BASICALLY THE
143 /CALLING SEQUENCE FOR OS/8 DEVICE HANDLERS.
144 /THE CALLING SEQUENCE IS:
147 / CIF MFIELD /MFIELD=FIELD ASSEMBLED IN
148 / JMS ENTRY /ENTRY=ORIGIN (EVEN NUMBERED DRIVE
149 /AND ORIGIN+4 FOR ODD NUMBERED DRIVE.
159 /ARG1: FUNCTION WORD BIT0: 0=READ, 1=WRITE
160 / BITS 1-5: UNUSED, WAS # BLOCKS IN OPERATION (DJG)
161 / BITS 6-8: FIELD OF BUFFER AREA
163 / BIT 10: # OF WORDS/BLOCK.
164 / 0= WDSBLK, 1=WDSBLK-1
165 / BIT 11: 1=START FORWARD, 0=REVERSE
166 /ARG1A: # OF BLOCKS IN OPERATIONA (DJG)
167 /ARG2: BUFFER ADDRESS FOR OPERATION
168 /ARG3: STARTING BLOCK FOR OPERATION
170 /ERRORS: THE HANDLER DETECTS TWO TYPES OF ERRORS:
171 /A) FATAL ERRORS- PARITY ERROR, TIMING ERROR,
172 / TOO GREAT A BLOCK NUMBER
173 / FATAL ERRORS TAKE ERROR RETURN WITH THE
175 /B) NON-FATAL- SELECT ERROR.
176 / IF NO PROPER UNIT IS SELECTED, THE ERROR
177 / RETURN IS TAKEN WITH CLEAR AC.
178 /FATAL ERRORS TRY THREE TIMES BEFORE TAKING ERROR RETURN.
179 /THE NORMAL RETURN IS TAKEN AFTER ALL INDICATED
180 /BLOCKS HAVE BEEN TRANSFERRED. THE AC IS CLEAR.
183 SDSS=7001-DRIVE /SKIP ON SINGLE LINE FLAG
184 SDST=7002-DRIVE /SKIP ON TIMING ERROR
185 SDSQ=7003-DRIVE /SKIP ON QUAD LINE FLAG
186 SDLC=7004-DRIVE /LOAD COMMAND REGISTER
187 SDLD=7005-DRIVE /LOAD DATA REGISTER
188 SDRC=7006-DRIVE /READ COMMAND REGISTER
189 SDRD=7007-DRIVE /READ DATA REGISTER
191 /THE IOT'S IN GENERAL ARE 677X,676X,675X,AND 674X.
192 /THE OTHERS CONTROL UNITS 2-7.
194 / THIS HANDLER USES DECTAPE BLOCKS NOT OS/8 BLOCKS !
198 / MODIFIED SO BIT 0 ON ENTRY IS UNIT 1
200 DCA UNIT /SAVE UNIT POSITION
202 TAD C6203 /GET DATA FIELD AND SETUP RETURN
204 TAD I DTA0 /GET FUNCTION WORD
205 SDLD /PUT FUNCTION INTO DATA REGISTER
206 CLL RTR /AC STILL HAS FUNCTION. PUT # WORDS PER
208 SZL CLA /KNOCK ONE OFF WDSBLK?
211 DCA WCOUNT /STORE MASTER WORD COUNT
212 ISZ DTA0 /TO BLOCK COUNT (DJG)
218 DCA XBUFF /SAVE ADDRESS (DJG)
220 ISZ DTA0 /TO BLOCK NUMBER
223 ISZ DTA0 /POINT TO ERROR EXIT
224 CIF CDF MFIELD /TO ROUTINES DATA FIELD
225 / SDRD /GET FUNCTION INTO AC
227 / AND CM200 /GET # PAGES TO XFER
230 AND C70 /GET FIELD FOR XFER
231 TAD C6201 /FORM CDF N
232 DCA XFIELD /IF=0 AND DF=N AT XFER.
234 DCA TRYCNT /3 ERROR TRIES
235 TAD UNIT /TEST FOR SELECT ERROR
237 CLA / Moved here because my drive 1 is slow selecting
239 DCA TRYCNT /3 ERROR TRIES
244 SDRD /PUT FUNCT INTO XFUNCT IN SECOND PG.
248 SDRD /GET MOTION BIT TO LINK
250 XFIELD, HLT /INTO NEXT PAGE
251 JMP GO /AND START THE MOTION.
252 RWCOM, SDST /ANY CHECKSUM ERRORS?
253 SZA CLA /OR CHECKSUM ERRORS?
254 JMP TRY3 /PLEASE NOTE THAT THE LINK IS ALWAYS
255 /SET AT RWCOM. GETCHK SETS IT.
256 / TAD PGCT /NO ERROR..FINISHED XFER?
261 JMP EXIT /ALL DONE. GET OUT
262 / DCA PGCT /NEW PAGE COUNT
263 ISZ BLOCK /NEXT BLOCK TO XFER
264 / TAD WCOUNT /FORM NEXT BUFFER ADDRESS
267 / DCA XBUFF /SAVE ADDRESS (DJG)
269 CLL CML /FORCES MOTION FORWARD
270 GO, CLA CML RTR /LINK BECOMES MOTION BIT
272 TAD UNIT /PUT IN 'GO' AND UNIT #
273 SDLC /LOOK FOR BLOCK NO.
275 TAD XBUFF /SAVE LOC OF BLOCK START SO
276 DCA OLDBUF /CAN RETRY ON ERROR
280 JMS I CRDQUD /WAIT AT LEAST 6 LINES TO LOOK
282 CM200, 7600 /COULD HAVE SAVED A LOC. HERE
284 JMP .-1 /WAIT FOR SINGLE LINE FLAG
286 CLL RTL /DIRECTION TO LINK. INFO BITS
288 AND C374 /ISOLATE MARK TRACK BITS
289 TAD M110 /IS IT END ZONE?
290 SNA /THE LINK STAYS SAME THRU THIS
292 TAD M20 /CHECK FOR BLOCK MARK
295 SDRD /GET THE BLOCK NUMBER
296 SZL /IF WE ARE IN REVERSE, LOOK FOR 3
297 /BLOCKS BEFORE TARGET BLOCK. THIS
298 /ALLOWS TURNAROUND AND UP TO SPEED.
302 CMA /IS IT RIGHT BLOCK?
304 JMP FOUND /YES..HOORAY!
305 M110, SZL SNA CLA /NO, BUT ARE WE HEADED FOR IT?
306 /ABOVE SNA IS SUPERFLUOUS.
308 ENDZ, SDRC /WE ARE IN THE END ZONE
309 CLL RTL /DIRECTION TO LINK
310 CLA /ARE WE IN REVERSE?
311 JMP GO /YES..TURN US AROUND
312 /IF WE ARE IN THE END ZONE GOING FORWARD, IT IS AN ERROR
314 OLDFLD, NOP /RESET FIELD
315 TAD OLDBUF /RESET BACK TO START OF BLOCK
319 JMP FATAL /LINK OFF MEANS AC=4000 ON RETURN
321 CLL CML /AC=0 ON NORMAL RETURN
332 /WCOUNT, 0 (MOVED PAGE 0 DJG)
334 /MWORDS, -WDSBLK (MOVED PAGE 0 DJG)
346 FOUND, SZL CLA /RIGHT BLOCK. HOW ABOUT DIRECTION?
347 JMP GO /WRONG..TURN AROUND
348 TAD UNIT /PUT UNIT INTO LINK
350 C70, 70 /********DON'T MOVE THIS!!!!******
352 / TAD BUFF /GET BUFFER ADDRESS (DJG)
353 /XFIELD, HLT /INTO NEXT PAGE
356 / DCA XBUFF /SAVE ADDRESS (DJG)
362 JMP .-1 /LOOK FOR REVERSE GUARD
365 TAD CM32 /IS IT REVERSE GUARD?
367 JMP REVGRD /NO.KEEP LOOKING
369 DCA WORDS /WORD COUNTER
370 TAD XFUNCT /GET FUNCTION READ OR WRITE
372 JMP READ /NEG. IS WRITE
374 AND C300 /CHECK FOR WRITE LOCK AND SELECT ERROR
375 CLL CML /LOCK OUT AND SELECT ARE AC 0 ERRORS
377 JMP I CFATAL /FATAL ERROR. LINK MUST BE ON
378 JMS RDQUAD /NO ONE EVER USES THIS WORD!
381 TAD XUNIT /INITIATE WRITE MODE
384 JMS WRQUAD /PUT 77 IN REVERSE CHECKSUM
387 WRLP, TAD I XBUFF /GLORY BE! THE ACTUAL WRITE!
389 ISZ XBUFF /BUMP CORE POINTER
390 JMP STFLD1+1 /NOT AT END OF FIELD (DJG)
395 ISZ WORDS /DONE THIS BLOCK?
396 JMP WRLP /NOT YET..LOOP A WHILE
397 TAD XFUNCT /IS THE OPERATION FOR WDSBLK PER BLOCK?
398 CLL RTR /IF NO, WRITE A 0 WORD
400 JMS WRQUAD /WRITE A WORD OF 0
401 JMS GETCHK /DO THE CHECK SUM
402 JMS WRQUAD /WRITE FORWARD CHECKSUM
403 JMS WRQUAD /ALLOW CHECKSUM TO BE WRITTEN
405 K77, 77 /ABOVE MAY SKIP (NOT ANYMORE DJG)
408 JMS RDQUAD /SKIP CONTROL WORDS
410 TAD K7700 /TACK 7700 ONTO CHECKSUM.
411 DCA CHKSUM /CHECKSUM ONLY LOW 6 BITS ANYWAY
413 JMS EQUFUN /COMPUT CHECKSUM AS WE GO
414 DCA I XBUFF /IT GETS CONDENSED LATER
415 ISZ XBUFF /AT END OF FIELD?
416 JMP STFLD2+1 /NOT AT END OF FIELD (DJG)
421 ISZ WORDS /DONE THIS OP?
422 JMP RDLP /NO SUCH LUCK
423 TAD XFUNCT /IF OP WAS FOR WDSBLK-1, READ AND
424 CLL RTR /CHECKSUM THE LAST TAPE WORD
427 JMS RDQUAD /NOT NEEDED FOR WDSBLK/BLOCK
428 JMS EQUFUN /CHECKSUM IT
429 RDLP2, JMS RDQUAD /READ CHECKSUM
432 JMS GETCHK /GET SIX BIT CHECKSUM
434 C300, 300 /PROTECTION (NOT ANYMORE DJG)
436 WRQUAD, 0 /WRITE OUT A 12 BIT WORD
437 JMS EQUFUN /ADD THIS TO CHECKSUM
438 SDSQ /SKIP ON QUADLINE FLAG
440 SDLD /LOAD DATA ONTO BUS
441 CLA /SDLD DOESN'T CLEAR AC
444 RDQUAD, 0 /READ A 12 BIT WORD
451 EQUFUN, 0 /COMPUTE EQUIVALENCE CHECKSUM
453 DCA EQUTMP /ACTUALLY CHECKSUMS ON DECTAPE ARE
454 TAD EQUTMP /EQUIVALENCE OF ALL WORDS IN A RECORD
455 AND CHKSUM /SIX BITS AT A TIME. BUT SINCE EQUIVALENCE
456 CIA /IS ASSOCIATIVE, WE CAN DO IT 12
457 CLL RAL /BITS AT A TIME AND CONDENSE LATER.
458 TAD EQUTMP /THIS ROUTINE USES THESE IDENTITIES:
459 TAD CHKSUM /A+B=(A.XOR.B)+2*(A.AND.B)
460 DCA CHKSUM /A.EQU.B=.NOT.(A.XOR.B)=A.XOR.(.NOT.B)
461 TAD EQUTMP /A.EQU.B=(A+(.NOT.B))-2*(A.AND.(.NOT.B))
465 GETCHK, 0 /FORM 6 BIT CHECKSUM
473 CLA CLL CML /FORCES LINK ON AT RWCOM
489 RETRY, 7776 / RETRY UP TO 1 TIME
490 NUMBLK, 2702 / NUMBER OF BLOCKS
491 MWORDS, -WDSBLK / WORDS PER BLOCK
493 BLKFLD, 37 / BLOCKS PER FIELD, 31 MAX FOR 129 WORDS/BLOCK
494 / WRAPPING PAST END OF LAST FIELD DOESN'T WORK
496 RDSIZE, 0 / NUMBER BLOCKS PER READ
497 CBLOCK, 0 / CURRENT BLOCK TO XFER
509 OLDBUF, 0 / USED BY DTA0 ROUTINE
510 XBUFF, 0 / USED BY DTA0 ROUTINE
511 C374, 374 / USED BY DTA0 ROUTINE
512 BLOCK, 0 / USED BY DTA0 ROUTINE
527 / HLT / Normal good halt
528 / JMP START / And restart if requested
541 CLA CLL / Get max field
547 HLT / Must have at least 1 field for buffer
550 RDSZLP, TAD BLKFLD / Multiply by number of fields available
553 DCA RDSIZE / NUMBER BLOCK PER READ
559 TAD DONEFG / If all transfered do finish stuff
562 TAD RDSIZE / Always ask for maximum number of blocks
563 DCA ARGSZ / Will accept less
564 TAD CBLOCK / The serial read routine uses these variables
569 JMS PUN / ASK FOR UP TO THIS MANY BLOCKS
572 DCA BCNT / Our block counter
574 INBL1, JMS INBLK / Get a block
575 JMP GOTALL / If Not last block
576 TAD ARGSZ / Is last block, calculate number received
578 SNA / If no blocks transfered must be done flag
579 JMP DONE / Do finish processing
580 DCA ARGSZ / Else write data received
585 GOTALL, ISZ CBLOCK / Go get next block
588 WRTIT, CDF 0 / Got all, write them out
591 4010 / ONLY EVEN # WORDS/BLOCK WORKS
596 JMP DUMPLP / Go get more
598 DONE, CLA / Send a character to get checksum
603 JMS GETCH / Convert the 2 bytes to 12 bit word
604 RTL / Shift low 4 bits to top 4
613 SZA / Checksum received is - sum so should be 0
614 HLT / Give up if not, serial error
616 TAD ARGSZ / Get size of last block written for first
617 DCA ARGSZ2 / to reread
618 TAD CBLOCK / And last block number
620 TAD TEMP / Store checksum received in our checksum
621 DCA CHKSM / Should give 0 at end
623 TAD ARGSZ2 / Decrease block number by number of blocks to
624 CIA / Read so we read starting at first block
625 TAD ARGBK2 / Read routine can't read backward
628 JMS DTA0 / REREAD AND CHECK
634 TAD ARGSZ2 / Checksum over number of blocks read
639 SUMIT, JMS SUMBLK / Sum each block
643 TAD RDSIZE / Read full blocks for rest of read
645 TAD ARGBK2 / If at block 0 then we are done
649 TAD CHKSM / Leave AC with checksum, should be 0
656 INBLK, 0 / Read a block of data from serial port
657 CLA / Read block size words
660 JMS GETCH / Get start of block flag
665 TAD (-1 / Is it end of data flag?
667 HLT / Not it, give up, we lost sync on serial data
668 ISZ INBLK / Return end of data state
671 JMS GETCH / Get 3 bytes and convert to 2 words
676 RTL / Shift low 4 bits to top 4
684 TAD CHKSM /Keep checksum of all words received
687 JMP STFLD3+1 /NOT AT END OF FIELD (DJG)
688 RDF /At end, inc field
692 ISZ LEN /END IF BUFFER?
694 JMP I INBLK /YES, DONE
709 JMP STFLD4+1 /Not at end of field
710 RDF /At end, inc field
718 SUMBLK, 0 / Sum a block of memory
723 TAD CHKSM / Keep checksum of all words
726 JMP STFLD5+1 /Not at end of field
727 RDF /At end, inc field
735 PUN, 0 / Send a character
736 / PLS / Punch for testing with emulator
737 TLS2 / Send out console
741 TSF2 /Wait until character sent
746 GETCH, 0 / Get a character
750 KSF2 / Have character waiting
751 JMP .-1 / No, try again