[sebhc] Tape images

[Carroll Waddell]

Let me correct myself. I loaded the tapes into the H8. Then changed the 
NORM INTCG switch to INTHG. Then pressed the dump key on the H8. This 
sent the tape from memory to my PC just as if I had written another copy 
of the tape. The H8 recreates the CRC after the data is written (Done by 
PAM-8) and writes the CRC.

About the PID, my memory is a little foggy. I retired from IBM in 92, 
but I THINK that PID was Program Information Distribution. Program 
changes or updates came on reels of tape. That is the only reason that I 
associated the PID with a tape.

Also, if you can find a PAM-8 listing, you can find the routines there 
to read, write, generate, and check the data and CRC.
Carroll

Steven Parker wrote:

> Carroll says:
>
>> I copied the original Heath tapes, byte for byte, to my PC, and gave 
>> them the PID extension.
>
>
> So that really is from the tape then, not memory contents dumped back 
> out again?  That would explain one curious thing I noticed, too.  
> While the format doesn't define any bytes after the crc, the PID files 
> all contain $FF after it.   BUT..if you had dumped them with PAM-8 
> they would contain a 2nd copy of the CRC instead.  I never knew how 
> the tapes were manufactured (on the other hand, I designed the program 
> that manufactured the diskettes).
>
> It's nice also to know where the name PID came from too.  :-)  But.. 
> do the letters stand for anything?
>
> Cheers,
>
> - Steven
>
> _________________________________________________________________
> Is your PC infected? Get a FREE online computer virus scan from 
> McAfee® Security. 
> http://clinic.mcafee.com/clinic/ibuy/campaign.asp?cid=3963
>
> -- 
> Delivered by the SEBHC Mailing List
>

--
Delivered by the SEBHC Mailing List