Assembly listing generated by yaYUL

Source Code

These source-code files are part of a reconstructed copy of Corona 261, the final, flown release of the Block I Command Module (CM) Apollo Guidance Computer (AGC) software for the AS-202 mission.

They have been created via disassembly of binary dumps of the original core rope memory modules actually flown on the mission, part numbers 1003733-171, 1003733-241, 1003733-191, 1003733-211, 1003733-221, and 1003733-241. The source code for the Apollo 4 and 6 software, Solarium 55, was used as a starting point, since it was directly derived from Corona and (at least in theory) only minimally modified.

Since only binary dumps (rather than listings) of Corona are available as source material, all comments and labels are approximate. They have been taken from other AGC programs where possible, or, in some places, written from scratch to match what we believe would have been in the original listing.

010889,000002: 010890,000003: 010891,000004: 010892,000005: 010893,000006: 010894,000007: 010895,000008: 010896,000009: 010897,000010: 010898,000011: 010899,000012: 010900,000013: 010901,000014: 010902,000015: 010903,000016: 010904,000017: 010905,000018: 010906,000019: 5654 010950,000063: ## Copyright: Public domain. ## Filename: INTER-BANK_COMMUNICATION.agc ## Purpose: A section of Corona revision 261. ## It is part of the source code for the Apollo Guidance Computer ## (AGC) for AS-202. No original listings of this software are ## available; instead, this file was created via disassembly of ## the core rope modules actually flown on the mission. ## Assembler: yaYUL ## Contact: Ron Burkey <info@sandroid.org>. ## Website: www.ibiblio.org/apollo/index.html ## Mod history: 2023-05-27 MAS Created from Solarium 55. # THE FOLLOWING SUBROUTINES ARE INTENDED TO FACILITATE INTER-BANK COMMUNICATION. ROUTINES ARE PROVIDED # FOR JUMPING TO A LOCATION IN ANOTHER BANK, CALLING A SUBROUTINE IN ANOTHER BANK, AND OBTAINING DATA FROM ANOTHER # BANK. IN ADDITION, A ROUTINE IS PROVIDED FOR MAKING UP A RETURN_ADDRESS CADR FOR USE BY THE CALLED SUBROUTINE. BANK 2 C4C">010907,000020: 5654 50062 BANKCALL TS ADDRWD # SUBROUTINE CALL WITH TRANSMISSION BOTH 30001 XCH Q # WAYS IN A. THE CADR OF THE CALLED 64516 AD ONE # ROUTINE SHOULD IMMEDIATELY FOLLOW THE 50001 TS Q # TC BANKCALL. 20000 INDEX A 27777 CAF 0 -1 # PICK UP CADR AND FALL INTO SWCALL. >010914,000027: 5662 50071 SWCALL TS TEMQS # SWCALL IS ALOS USED TO CALL SUBROUTINES 30015 XCH BANKREG # IN OTHER BANKS, BUT THE CADR ARRIVES IN 50072 TS BANKTEM # A. DATA MAY BE TRANSMITTED BACK TO THE 30001 XCH Q # CALLING PROGRAM IN A, HOWEVER. 30071 XCH TEMQS # RETURN INFORMATION NOW COMPLETE. 50114 TS ESCAPE 72665 MASK 70K # PROVISION FOR CALLING A ROUTINE IN 10000 CCS A # FIXED-FIXED (OF QUESTIONABLE VALUE). 05674 TC +2 # SPECIAL TREATMENT REQUIRED IF NON-ZERO. 05676 TC +3 # INPUT CADR OK AS IS. 40015 CS BANKREG # FORM PROPER 12 BIT ADDRESS. 64373 AD 6K 60114 +3 AD ESCAPE # PROPER CADRS COME HERE WITH C(A) = 0. 30062 XCH ADDRWD # SO A CAN TRANSMIT WITH BANKCALL. 20062 INDEX ADDRWD 00000 TC 0 # SETTING Q TO SWRETURN. 24E">010932,000045: 5702 30072 SWRETURN XCH BANKTEM # RETURN TO CALLER, TRANSMITTING THROUGH A 50015 TS BANKREG 30072 XCH BANKTEM # RESTORE A AS UPON ARRIVAL TO SWRETURN. 00071 TC TEMQS # RETURN. 452">010938,000051: 5706 35501 MAKECADR CAF ZERO # LEAVES RETURN-ADDRESS CADR (AS SET BY 60071 AD TEMQS # SWCALL OR BANKCALL) IN ADDRWD. 50062 TS ADDRWD 62165 AD 32K # SEE IF BANK INFORMATION NEEDED (USUAL). 50034 TS OVCTR 00001 TC Q # ADDRWD SET OK IF NO OVERFLOW (IN FF). 30034 XCH OVCTR # CONTAINS LOW 10 BITS ONLY. 60072 AD BANKTEM 50062 TS ADDRWD # RETURN CADR NOW COMPLETE. 00001 TC Q 5720 2165 32K EQUALS PRIO32 D50">010951,000064: 5720 30001 POSTJUMP XCH Q # ONE-WAY BANK TO BANK JUMP, WITH NO 20000 INDEX A # RETURN ADDRESS. THIS VERSION TRANSMITS 30000 CAF 0 # THROUGH A IF DESIRED. D50">010955,000068: 5723 50015 BANKJUMP TS BANKREG # SAME AS ABOVE ONLY ADDRESS ARRIVES IN A. 74606 MASK LOW10 # BANKJUMP AND POSTJUMP MAY BE USED IN 30001 XCH Q # INTERRUPT OR UNDER EXEC, BUT BANKCALL 20001 INDEX Q # AND SWCALL MAY BE USED ONLY UNDER EXEC. 06000 TC 6000 C4C">010962,000075: 5730 50114 DATACALL TS ESCAPE # SUBROUTINE TO RETRIEVE DATA IN ANOTHER 30015 XCH BANKREG # BANK. THE CADR OF THE LOCATION OF INTER- 30114 XCH ESCAPE # EST ARRIVES IN A AND ITS CONTENTS ARE IN 74606 MASK LOW10 # A ON EXIT. THIS MAY BE USED ONLY UNDER 20000 INDEX A # EXECUTIVE. 36000 CAF 6000 # REQUESTED DATA NOW ACQUIRED. 30114 XCH ESCAPE 50015 TS BANKREG 30114 XCH ESCAPE 00001 TC Q # THE FOLLOWING ROUTINES ARE INTERRUPT ANALOGS OF BANKCALL AND SWCALL. BANK-TO-BANK ONLY. C4C">010977,000090: 5742 50637 IBNKCALL TS RUPTREG1 30001 XCH Q 64516 AD ONE 50001 TS Q 20000 INDEX A 27777 CAF 0 -1 C">010984,000097: 5750 50641 ISWCALL TS RUPTREG3 30015 XCH BANKREG 50640 TS RUPTREG2 30001 XCH Q 30641 XCH RUPTREG3 74606 MASK LOW10 30637 XCH RUPTREG1 20637 INDEX RUPTREG1 06000 TC 6000 24E">010994,000107: 5761 30640 ISWRETRN XCH RUPTREG2 50015 TS BANKREG 30640 XCH RUPTREG2 00641 TC RUPTREG3 INTER-BANK_COMMUNICATION.agc. Parent file is MAIN.agc