MaxTransfer , how and where.

[leytond]

could this be the root of my problems installing classicwb,
all i get is error code 50 while trying to unpack to hdd on a real amiga, not that emulator rubish. ive heard "MaxTransfer" could be the problem, where is it , what is it, and can i alter it,

[Matt_H]

Open up HDToolBox. On the change file system page, you should see a string gadget containing the max transfer value. Change it to 0x0001FE00. You might need to reformat afterwards.

[leytond]

string gadget containing the max transfer value. Change it to 0x0001FE00
first, im a total newb to this as they call me on eab,
second what is a string gadget and what dose it look like, .
third reformat, that means that i have to put os back on,

[Ilwrath]

string gadget containing the max transfer value. Change it to 0x0001FE00

It's just a spot where you can type in a value.  It'll probably have 0xFFFFFFFF in it.  That is a bad value.  The A1200 HD controller has a nasty buffer bug that shows up on certain hard drives.  The Max Transfer value needs to be something much smaller.  There is some debate over what an optimal value is, but that 0x0001FE00 should work.  

third reformat, that means that i have to put os back on,

You won't HAVE to.  But, the problem is, while the max transfer was incorrectly set, every file larger than about 256kB or so written to that hard drive has a chance of being corrupt.  Who knows how many problems are lurking undiscovered in a system like that.

[Zac67]

0x0001FE00? Where does that value come from?

I've always had the impression that 64K is a limit on some systems, so something like 0x0000FF00 would be logical (wouldn't make much of a performance difference anyway). Could someone enlighten me?

PS: didn't know about the 1200 IDE bug, my systems have always been 'pure SCSI'. ;-)

[leytond]

i dont get it, if its going to corrupt the files what is the point of doing it,
wont it fix it, .

[Ilwrath]

i dont get it, if its going to corrupt the files what is the point of doing it,
wont it fix it, .

The files already copied may already be corrupt.  You can't do anything about those.  That's why it's recommended to format and reinstall.

Setting the new value will allow NEW files written to the drive to be written properly.

[leytond]

right ill go and give it a go, but knowing my luck ill be back with a ton of questions.
nothing works with this amiga,

[Ilwrath]

0x0001FE00? Where does that value come from?

I've always had the impression that 64K is a limit on some systems, so something like 0x0000FF00 would be logical (wouldn't make much of a performance difference anyway). Could someone enlighten me?

I'm not positive.  Personally, I ran 0x0001FFFF back in the day.  That was what the local C= dealer recommended.  I've heard all three values cited.  I've never heard of anyone having problems at 0x0001FE00 or less, though.  (And, personally, I never had any problems at 0x0001FFFF on a drive that had loads of problems at the default value.)

[davideo]

The thing to remember with changing the max transfer value is to make sure that you press ENTER/RETURN otherwise the value won't be saved.

Dave G  8-)

[alexh]

Ilwrath wrote:
0xFFFFFFFF is a bad value.  The A1200 HD controller has a nasty buffer bug that shows up on certain hard drives.

AFAIK the bug is not with the Amiga but in the drives.

Zac67 wrote:
0x0001FE00? Where does that value come from?

Unknown. Trial and error? It should be just less than 128Kbytes or 64Kbytes (the two most common maximum sizes used by OS's today) Windows uses 64Kbytes. Some CF cards are very picky and people have said the only transfer size that worked for them was 0x0000FE00

[leytond]

well yep i changed it , and yes pressing enter sure dose help, as i found out,.
well like i said ive done it, i dont know what its supposed to do , but my hard drive is still working,
what is it supposed to do??

[Matt_H]

It reduces the amount of data copied in a single "cycle" of a disk transfer operation. It's set fairly high by default (good for SCSI drives), but IDE drives tend to barf on it, resulting in corrupt data. The new values you've seen in this thread should help.

Also note that you need to make the change for every individual partition.

If you're new to the Amiga, be aware of the infamous >4GB problem. What size is your drive?

[leytond]

my drive partisions aer.
dh0: 2gig
dh1: 10 gig
dh2: 10 gig
dh3: 10 gig
 and the os3.5 with 2 boing thingy updates.

[Trev]

And based on past observations, I'm under the impression this is a signed value, so 0x7fffffff would be the max, anyway. Anyone know for sure? Dependent on the device driver's interpretation of the data?