[vcf-midatlantic] Found: VMS Hobbyist CDs

Jonathan Gevaryahu jgevaryahu at gmail.com
Tue Jun 6 15:05:28 EDT 2017

AFAIK OSes which require drives with '512 byte blocks' is sort of a scsi 
The physical data on the cd surface is 2048 byte blocks (plus ECC and 
subchannel data you don't normally see for 2532 bytes per sector, plus 
headers and sync marks etc)
The whole 512 byte thing is a special mode certain cd drives have which 
sends each 2048 byte block to the host computer as if it was four 
separate 512 byte blocks/sectors, but its really just a translation 
layer. Not all drives do it.

The actual CD contents for these VMS cds are 2048 byte blocks, the 512 
byte magic happens in the drive, AFAIK.

I could be wrong about this.

On 6/5/2017 12:48 PM, Brian Schenkenberger via vcf-midatlantic wrote:
> Neil Cherry via vcf-midatlantic writes:
>> On 06/03/2017 11:21 PM, Jim Scheef wrote: > Neil, > Could you pull ISOs
>> of a couple of the CDs before you take them to IA? > Jim
>> I'm using my Linux box to see if I can copy the entire CD to an image. I
>> don't know how well this will work but it won't take much space.
> http://tmesis.net/OpenVMS_Hobbyist/

Jonathan Gevaryahu
jgevaryahu at gmail.com
jgevaryahu at hotmail.com

More information about the vcf-midatlantic mailing list