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Re: What is the largest drive that NetBSD/VAX will support?

On 2016-02-19 14:25, Mark Pizzolato wrote:
On Friday, February 19, 2016 at 12:00 AM, John Klos wrote:
I'm currently setting up a new project. In this case its an
arrangement of SIMH/VAX running on Linux/I386. The host has a Zip100
drive installed. And as it happens I'm wondering, with this issue:
"What is the largest drive that NetBSD/VAX will support?". Conversely
it becomes "What is the smallest drive that NetBSD/VAX will support?".

The largest drive it'll support without any extra fuss, I think, would be
2 TB (2^32-1 blocks of 512 bytes each). The smallest, I think, would be one

That is indeed the upper limit.  I can't imagine any amount of 'fuss' which
could extend it beyond that.  The boundary is based on the fact that the
MSCP protocol has a 32bit field containing the logical block number (thus
the 2^32-1) and all sectors are 512 bytes.  This is a limit of the hardware being
simulated due to the structure of the MSCP protocol.

Noone forces you to use MSCP. There are VAXen with SCSI as well. However, disk labels also limit you to 2^32 blocks, or something like that, so there are several subsystems that might cause issues with larger disks.


Johnny Billquist                  || "I'm on a bus
                                  ||  on a psychedelic trip
email: bqt%softjar.se@localhost             ||  Reading murder books
pdp is alive!                     ||  tryin' to stay hip" - B. Idol

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