Hello Johnson,

>>good news: version 2.2 now reads DVD's completly, no bugs
>>
>>bad news: unfortunately it's about as slow as (PIO-only) CDROM.SYS, 4
>>times slower the 2.0. So any advantage is gone

> Did you see the "ATA-33" message?
yes. but ATA-33 is still fast enough.

problem is, that /UF has changed meaning.

now (without /UF) if crossing a UDMA everything is done using PIO mode

this is a) different from UDMA/XDMA, which are much more clever

and b) rather stupid: even a 62Kb read to 2800:0000 is handled with
PIO only, where the driver could easily split it into 2 reads of
   32kb --> 2800:0000
   30kb --> 3000:0000


another thing:
I found a CD, which isn't 'easily' readable

symptom: when I access it (through XCDROM), I get pseudo-random read
errors, i.e. offset XYZ is readable *sometimes*, but not *always*

the legacy CDROM.SYS handles this much better.

looks like it retries on CRC-errors a few times, until it gives up,
and that this strategy helps (a bit)

Tom



-------------------------------------------------------
This SF.net email is sponsored by: Splunk Inc. Do you grep through log files
for problems?  Stop!  Download the new AJAX search engine that makes
searching your log files as easy as surfing the  web.  DOWNLOAD SPLUNK!
http://sel.as-us.falkag.net/sel?cmd=lnk&kid=103432&bid=230486&dat=121642
_______________________________________________
Freedos-devel mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/freedos-devel

Reply via email to