RL02-USB Controller Status/Problem

Pete Turnbull pete at dunnington.plus.com
Tue Apr 7 12:21:55 CDT 2015

On 07/04/2015 16:25, Paul Koning wrote:
>> On Apr 7, 2015, at 8:41 AM, Pete Turnbull
>> <pete at dunnington.plus.com> wrote:

>> DEC does it by having the driver software remap sectors.
> No, DEC does not do that.  At least not in RSX, as Johnny described,
> nor in RSTS.

I worded it poorly.  The driver provides the data to remap blocks, but 
doesn't necessarily use a replacement when it gets an error.  As I wrote 
elsewhere, there are two mechanisms: the files called FILE.BAD being 
analogous to the file BADBLK.SYS in RSX, and the bad block substitution 
table in the home block which is used when you perform normal file 
operations - and which only exists for devices such as RL01/02 and 
RK06/07, and is stored in the driver's memory-resident tables.  I don't 
know in detail how substitution happens, but in RT-11, it does.


Pete Turnbull

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