tape reads, count mod 8 = 7

[utzoo!decvax!harpo!floyd!cmcl2!philabs!sdcsvax!sdcsla!stanonik]

We're seeing a problem when we try to read tape records whose
count mod 8 is 7.  The last byte is ok, but the previous 6 
have been replaced with nulls.  Below are od's of records 
with counts 23 and 31.  (The final null is an artifact of od.)
We're running 4.1bsd on a 780 with a Kennedy 9300 drive and
a Western Peripherals tc-131 controller.  Seen it before?  

Why, you ask do we want to read tape records with count mod 8 
equal 7?  "Lisp Machine dump tapes" is the answer.

Thanks,

Ron Stanonik
...!sdcsvax!stanonik
stanonik at nprdc

0000000 000 001 002 003 004 005 006 007 010 011 012 013 014 015 016 017
0000020 000 000 000 000 000 000 026 000
0000027

0000000 000 001 002 003 004 005 006 007 010 011 012 013 014 015 016 017
0000020 020 021 022 023 024 025 026 027 000 000 000 000 000 000 036 000
0000037