Once we baked it & replaced the band, The tape is clearly in Kennedy 6450 format. However, the first VERY strange thing about it is that it doesn't have a preamble! So, we had to do some really fancy footwork to extract what we have of it. However, it would be difficult (more so than what we've done so far) to reliably use the CRC to correct it, because we have NO idea how long the data block is supposed to be. This data block is LONGER than we've ever seen before. Previously, we've seen 4096 & 8192 byte blocks. This one is AT LEAST 13,488 bytes (which is an odd length?), possibly more. Since the preamble is missing, who really knows what or how much goes in front of what we have been able to restore.
I should also mention that it appears that there are 3 blocks of data, all 3 without a preamble, and they appear to be mostly identical. It is my guess that when the system wrote them, it made 3 attempts, where the first 2 failed, or maybe all 3 failed, and that's when the system gave up. Regardless, it is the 3rd of the 3 blocks present that we used, because it was not only the largest in size, but seemed most complete, and visually with the fewest errors...although we really don't know that for sure...
A download of the binary extracted from the 3rd block can be downloaded here, in its unmodified form:
KENNEDY BACKUP DISC UTILITY.BIN
We did modify the bytes by dropping the highest order bit for each byte (but NOT reversing the endian-ness), to reveal readable text strings within. That can be downloaded here:
KENNEDY BACKUP DISC UTILITY (Highest Order Bit Dropped).BIN
I recommend viewing either of these with some HEX editor. I use HxD
When we did drop the highest order bit, it revealed these interesting text strings:
POINT 4 DISK SUBSYSTEM UTILITY
VERSION 1.4 SEP 17 1980
FOR HELP ANYTIME, TYPE 'H'
PROGRAM NAME: FORMAT ANALYZE COPY FORMAT,ANALYZE H C R X Y N WHAT? BUFFER FULL, RE-ENTER
TYPE OF DRIVE: DRIVE NUMBER: SURFACE(S): SOURCE DRIVE - TYPE: NUMBER:
COPY TO THE SAME DRIVE? TO
DESTINATION DRIVE - DRIVE NUMBERS CONFLICT
PROGRAM PURPOSE
FORMAT TO INITIALIZE DISK WR SURFACES ANALYZE TO ANALYZE PRE-FORMATTED WR SURFACES COPY TO DUPLICATE DISK FILES
0 THRU 3 ONLY
INITIAL DEFAULT IS DRV 0; SUBSEQUENT DEFAULT IS NO CHANGE
0 THRU DEFAULT = ALL SURFACES
FLAG TO FLAG ALL SECTORS OF HARD ERROR BAD C TO CONTINUE DISPLAY R TO RESTA `?AiIiQiYi pAh ^! i? ]
ZDIGIDYNE VIRTUAL CONSOLE (REV 1.5) F FPC = % ? @O
PC = )S+ IQ 8 != !7)71797 H .UMP * *ADDR? #I=
m !C = )6 c EY
64KW ENABLED (YES=1, NO=0)?
....
H'E gI ObI*r L J W 32 8
CDC300 SMD 300MB 823 19 32 9766 9
CDC12 MMD 12MB 320 2 32 10
CDC25 MMD 25MB 320 4 32 11
CDC82 MMD 82MB 823 5 32 12
CDC.9 MMD 0.9MB 12 4 32 13
CDC1 MMD 1MB 10 5 32 14
CDC2 MMD 2MB 20 5 32 15
CDC16 CMD 16MB 808 1 32 16
CDC16F FMD 16MB 808 1 32 17
CDC48F FMD 48MB 808 3 32 18
CDC80F FMD 80MB 808 5 32 25
AMP40 SMD 40MB 411 5 32 26
AMP80 SMD 80MB 823 5 32 DM-980 27
AMP100 SMD 100MB 411 19 21 28
AMP150 SMD 150MB 561 14 32 29
AMP160 SMD 160MB 1645 5 32 DM9160 30
AMP200 SMD 200MB 815 19 21 31
AMP300 SMD 300MB 815 19 32 DM9300 32
AMP16 CMD 16MB 823 1 32 33
AMP16F FMD 16MB 823 1 32 34
AMP48 FMD 48MB 823 3 32 35
AMP80F FMD 80MB 823 5 32 40
MMX25 SMD 25MB 350 4 28 601 41
MMX50 SMD 50MB 350 8 28 601 42
MMX75 SMD 75MB 350 12 28 601 43
MMX100 SMD 100MB 411 19 21 677 44
MMX200 SMD 200MB 815 19 21 677 48
FUJ40 SMD 40MB 815 3 32 40 50
OKI13 13MB 339 2 32 3301 51
OKI26 26MB 339 4 32 3302 52
OKI40 40MB 339 6 32 3303 53
OKI50 50MB 339 8 32 3304 54
OKI67 67MB 339 10 32 3305 55
OKI80 FMD 80MB 339 12 32 3306 60
CAL25 25MB 407 5 23 T25 61
CAL50 50MB 815 5 23 T50 62
CAL80 80MB 815 5 32 T82 63
CAL200 200MB 815 19 23 T200 64
CAL300 300MB 815 19 32 T302 70
MCD12 12MB 350 2 28 71
MCD37 37MB 350 6 28 72
MCD62 62MB 350 10 28 75
KEN14 14MB 700 1 32 76
KEN42 42MB 700 3 32 77
KEN70 70MB 700 5 32
None of the text strings within say anything about "Kennedy". So, there must have been a mental association on behalf of whoever hand-wrote on that tape, between the brand of the tape drive, and the maker of the utility. It probably goes no further than that, because I find no evidence of Kennedy & Point 4 ever being mentioned together.
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Does anyone have any idea, knowledge or insight on this?
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Here is a video on the painstaking process we used to restore the single block without a preamble.
As a complement to these videos, here is a download of the original 19Mb .logicdata capture file that we used from Track 0 of this tape, (which is the only track that seemed to have any data at all, and then only the 3 blocks we saw at the beginning).
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