SCSI speed

Kawazu

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Joined
Oct 22, 2010
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I noticed a post on another forum, think it was amiga.org where they compared scsi speed.

Some where hitting the 30mb/s mark with the same setup that i have so i thougt i give it a go and test my own system. I ended up at 8mb/s when i used sysinfo.

What can be done to increase the speed?
I have tried changing the settings in the CS PPC bios but that did not make much difference at all.

I have also been told that i can change the ID number of the SCSI HDD, how exactly do i do this? I know there are some jumpers on the HDD and i have that sett to 0 or 1 but still the CS PPC asign it to 2-3 or somthing. At work atm so cant check the exakt number.

Is there any scsi tool i can use to improve my MB/S on the disk or is there some other way to figure out whats wrong?

My cabel setup is

Terminator->CS PPC SCSI-> SCSI HDD -> Terminator

The terminators should be active? Dont rly know how to tell if they are or not.

Would be nice if some one could take a phot of their PPC bios so i can have a look how you guys set it up ( the hdd part that is)

Thx in advance
 
Use SysSpeed instead. :)
Please bear in mind that PFS is faster than standard Commodore FFS filesystem, so try PFS as well.
Hope you are using 68pin hdd, not 50pin?

Always use the same benchmark tool to compare benchmark results.
 
Use SysSpeed instead. :)
Please bear in mind that PFS is faster than standard Commodore FFS filesystem, so try PFS as well.
Hope you are using 68pin hdd, not 50pin?

Always use the same benchmark tool to compare benchmark results.

Have tried that to, same result :)

But i cant change the filsystem of the disk without formating it right?
Yes i am using a 68pin HDD.

I had a friend help me install the whole OS so i dont know what he picked out for me when it comes to file system :) But should a change of file system realy give me an increase of almost 20mb/s?
 
Hi mate

I'm using CSPPC's and UW-SCSI devices.

After reading manuals and testing with lot of devices..... In my systems, a good config of the SCSI Bios increases the overall performance of the system and make it more stable.

I assuming you're using UW-SCSI devices and Active terminators.....

My config...

- CSPPC SCSI Updated to the latest firmware 44.71
- Active terminator Passtrough 68 pins LVD/SE
- ID0 - Auto
- ID1 - HDD, Async, 16 bit bus, No Removable
- ID2 - HDD, Async, 16 bit bus, No Removable
- ID3 - HDD, Async, 16 bit bus, No Removable
- ID4 - DVD-RW, Async, 16 bit bus, Removable, CD AutoMount, CD4
- ID5 - DVD-RW, Async, 16 bit bus, Removable, CD Boot, CD5
- ID6 - Auto
- ID7 - SCSI Controller
- ID8 - Auto
............
- Active Terminator

That's all. I have around 21MB/sec in all devices. :wooha:

Take a look here https://www.amibay.com/showthread.php?t=16460&page=2

Maybe a little help for you? :)

Best wishes
 
Would you mind taking a photo on that ppc screen?

It sounds to me that mine and your do not look anything alike. And how exactly do i set the ID number?

Edit: And i am to scared to flash to the latest firmware. I probably destroy the card if i try.
 
@Kawazu

The ID's you must configure in the devices, HDD, DVD, ...... Normally all devices have jumpers to set the correct ID number.

Also, in most cases, the "Power terminator" (NOT the "Terminator") must be set to ON in all devices.

About the SCSI Bios menu I will try to post pics this evening/night.

Best wishes.
 
Downloaded Unitcontrol from phase 5. and i have selected 10bytes/ handshake and 40mb syncro and i get 25mb/s :D

The question is, do these settings stay put or do i have to change em every time :)

I am one happy amiga user atm :p

Well it dont save the settings, and in the PPC bios i can only set 20mb/s not 40mb/s like i do in unitcontrol.
So how do i get these settings aplied on every start?

Problem solved:

added this line in the startup

UnitControl Device=cybppc.device Unit=1 Period=20 Offset=10 Wide Reselection FWC

- 20MHz synchronous (40MB/Sec if combined with Wide)
- Wide (16-bit)
- 10Byte handshakes
- Reselection enabled
- Write cache enabled
 
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<SNIP>

Also, in most cases, the "Power terminator" (NOT the "Terminator") must be set to ON in all devices.<SNIP x2>


Never do this!

Just one HD or other device in the SCSI chain must be set to provide power to the SCSI bus, if the controller itself cannot do it.

In the case of the CSPPC, it don't provide termination power, so you need to set ONE device to provide power to the terminators.
 
Never do this!

Just one HD or other device in the SCSI chain must be set to provide power to the SCSI bus, if the controller itself cannot do it.

In the case of the CSPPC, it don't provide termination power, so you need to set ONE device to provide power to the terminators.

:wooha: :wooha: :wooha: I will try this evening/night.....

I have all my Acard's with this jumper set to ON, and everything is working fine for days without issues...... :shrug:

I will try set ON only one...... :)

Thanks for the info (y)
 
The problem here is all devices sending voltage to the cable. One will send, say, 4.97V. Other will send 5.00V.

If no protection (a diode to avoid returning current) from one device to the other you'll fry one or both.
 
Whooooo!!!! :wooha: :wooha: :wooha:

I must change my config now......

Thanks again for the info my friend :bowdown: :bowdown: :bowdown:

---------- Post added at 19:03 ---------- Previous post was at 18:46 ----------

@rkauer

Changed!!!!! :)

Now only one Acard have the "Power Terminator" closed (ON)....

Is needed with Active terminators? or also I need to leave open?
 
I have everything set to "Auto" in PPC Bootmenu.. and I'm gettting 25-32MB/s from my HDD according to SysSpeed. SysInfo show 21-25MB/s...
 
What happens if more are sett to power ON?

Not much actually. Practically all SCSI devices that (can) supply termination power do it through a diode and a fuse, as rkauer said, so no harm is done (which is why you won't find strong warnings against it in manuals, but rather moderate semi-warnings like 'only one device is needed to provide termination power' instead of 'one and only one device may provide termination power' ).
Still it's best to only let one device do it.
 
I have everything set to "Auto" in PPC Bootmenu.. and I'm gettting 25-32MB/s from my HDD according to SysSpeed. SysInfo show 21-25MB/s...

If I set all devices to Auto, I get some issues with my Acard's 7720UW, r/w erros, ..... Maybe is a problem derivated of using not real UWSCSI devices.

But, with manual config, everything works fast & stable. Maybe is not too much, but for me, an speed around 21MB/s is enough. :)

About "Terminator Power" jumpers... after rkauer alerts me I set to ON in one HDD and all other devices are OFF.... (I don't want to have one A4K-BBQ :D).

Best wishes
 
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Is needed with Active terminators? or also I need to leave open?

It is totally necessary with active terminators.

Passive units doesn't need power at all, active ones have electronic chips inside that demands power.

@BLTCON0: not ALL SCSI devices have a protection diode, some just have a power regulator with no inverse current protection at all. The regulator itself may act as a diode, but this can cause stress in such component that can make a chain reaction of one device popping off and carrying others in the short-circuit.
 
@rkauer

It is totally necessary with active terminators.

Passive units doesn't need power at all, active ones have electronic chips inside that demands power.

Thanks again for the info my friend :bowdown:. You're like a good SCSI Book (y)

Best wishes
 
I am like an open book.

Only some selected pages I ripped off (like fact I have an 2600 in the home).:blased:
 
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