See listJAN 23 196767-FM1-10FM/Deputy Chief, Mission Planning and Analysis DivisionAS-504 spacecraft computer program and storage status. Also a dash of AS-258.
On January 12 a great herd of us went to MIT to review the AS-504 space- craft computer program requirements, or at least the questionable items, to make sure we would not overflow the computer storage capability. The consensus of those present was that MIT had put together an excellent presentation defining, with considerable precision, the over-all computer storage situation as well as a very reasonable proposal on which to base our future work. This meeting had none or the fire and excitement of last May's Black Friday. In fact, this one in not worthy of that name.
In brief, MIT told us that presently defined programs exceed memory by about 2,000 words in both the CMC and LGC but that by the removal of certain pre-flight interface and system tests, along with a simple clean- up of the computer programming itself (such as removal of redundant sub- routines and constants), we could provide a positive margin of about 1,500 words.
The rest of the day, and the following morning, wan spent in discussion of programs identified by MSC and MIT an non-mandatory that are to be deleted either now or when more storage in needed. As a result of all that, we obtained potential pads of about 4,100 words in the LGC and 5,300 words in the CMC. These would result from making all thirteen dele- tions noted below in List 1. We also identified a number of potential changes and additions which are documented in the second list below with their presently agreed upon disposition. Obviously some of those absorb some of that precious pad, but I guess that's what it's for.
List 1 – Possible Deletions
A. Program to be removed immediately – no further effort to be expended.
B. Routine to remain in the program now but subject to later deletion – work to continue but on a low priority.
C. Routine to remain in the program now but subject to later deletion – no further effort required since the work is complete at this time.
[Note: Page 2 missing in source]
AS-258 AS-504 LGC CMC LGC CMC
6. CALCMANU maneuver to input gimbal F F E E angles
7. Transformation routine to align LM IMU F – D – docked
8. IMU align using reticle (to provide – D – E DSKY mark capability)
9. Rendezvous navigation using reticle – D – D
10. External targeting of Lambert steering F F E E
11. Erasable memory onto downlist D D E E
12. Trim option to P-40 and 42 E E E E
13. Perform desk calculator type function F F F F
14. S-band pointing angle display – – E D
15. Uplink – – E –
16. LR reasonableness check – – E –
17. Entry displays to be referenced to – D – E oblate earth
At least this is the way I think things stand. And now we'll start tak- ing calls from the audience.