Wanted: SIMH VAX VMS tape image tester, take 2

Chuck Guzis cclist at sydex.com
Sat Dec 20 15:09:05 CST 2014


On 12/20/2014 01:10 AM, Jochen Kunz wrote:

> Also keep in mind that JSON is a well defined standard, ECMA-404, and
> many people already know JSON.

Here's the problem.  JSON and XML assume some sort of formal structure.

I can think of a few standard items, but most of the relevant 
information will be narrative in nature.

There are some useful bits of information that could be incorporated, 
however.  For example, the code used to create the .TAP image also tries 
to summarize the layout of the tape blocks; e.g., for the sample VMS 
FORTRAN 4.5 tape:

5 x 80 bytes
Tapemark hit at block 6
47 x 9216 bytes
Tapemark hit at block 54
4 x 80 bytes
Tapemark hit at block 59
4 x 80 bytes
Tapemark hit at block 64
25 x 9216 bytes
Tapemark hit at block 90
4 x 80 bytes
Tapemark hit at block 95
Tapemark hit at block 96

That, and the identification of the drive used to read the tape and the 
density could be codified.

But what about the procedure used to extract real data and the identity 
and peculiarities of the logical tape format?

What about the context of the tape data itself?

--Chuck




More information about the cctech mailing list