EIDE Slave/Master

[quiksil903]

Hey

just installed a cd-rw in my secondary EIDE bay. what's the deal with this slave master jumper set-up?

the hardware recommended that I install it as a master either on primary or secondary eide and didn't explicitly recommend that it be installed on the same split ide cable as my other dvd/cd-rom that i am keeping, even though this woudl be the most convenient set up. otherwise, i would have to switch around the ide cables from my hard drive (which is currently master on 2ndary ide).

it would be much easier to just install the new burner as a slave as it is the 2nd bay from the top with my other cdr. does this matter/affect performance? right now i have it set up so the jumper is in the csel position (said something about my computer automatically deciding which was slave and which master. is this preferable or no? please advise.

thanks

-quik

 

[tk149]

1. All IDE devices have to be set up as either a Master device or a Slave device. Why? I don't know.

2. Your primary hard drive should be set up as a Master device. Preferably on IDE1.

3. If you want to record CD's directly from your DVD/CDROM drive, then you should put the CDRW on a separate IDE channel. This is because the IDE channel can only handle a limited amount of data at a time, so if you try reading and burning on the same IDE, you may get a bad burn because of buffer underruns.

4. If your motherboard supports more than two IDE channels, I'd recommend setting each drive you have as a Master.

5. If not, than I'd recommend setting your primary Hard Drive as the Master and your CDRW as the Slave on the same IDE channel.

5. Yes, it's a pain in the b*tt.

6. Caveat: This used to be the conventional wisdom. But with the larger CDRW buffers, I don't know if this logic still holds. I know that Nero 5.5 recommends this same setup.

 

[zephyrprime]

The whole slave/master thing is necesarry because the ide drives share the same wires and hence both receive the same data signals. The only way for the ide devices to distinguish which drive is actually being spoken with is to have a special address pin. When the signal on the special pin is one way, it means that the master is being communicated with. When the pin is the other way, the slave is being communicated with.

This is all been resolved with serial ata anyway.

 

[thorin]

"1. All IDE devices have to be set up as either a Master device or a Slave device. Why? I don't know."

Because although you can attach 4 devices there are only 2 channels and on each channel on 1 device can be accessed (talked to or alking) at once.

"2. Your primary hard drive should be set up as a Master device. Preferably on IDE1."

Yes primary HD (OS and Apps) should be Primary Master.

"3. If you want to record CD's directly from your DVD/CDROM drive, then you should put the CDRW on a separate IDE channel. This is because the IDE channel can only handle a limited amount of data at a time, so if you try reading and burning on the same IDE, you may get a bad burn because of buffer underruns."

Close. It doesn't have anything to do with the amount of data that the IDE channel can send (the current best drives on the market don't even challenge ATA66 standard IDE channels ... they max at about 40MB/Sec nowhere near 66). Source and destination drives should be on alternate channels so that the majority of the time you are reading one and writting the other at the same time (keeping in mind the point above for #1). Buffer underruns usually occur when the source media isn't fast enough or when the system is too busy, with BurnRight and other underrun protections and larger CDR(W) buffers this is less and less of an issue.

Therefore the most optimal solution is:

Primary Master - Primary HD containing OS and Apps
Primary Slave - Primary CDROM (CDR or CDRW) since you will usually burn from the other CDROM or the Secondary HD
Secondary Master - Secondary HD containing Games and other data (backups, archives, music collections etc)
Secondary Slave - Primary CDROM (the CDR you use to install things from)

"4. If your motherboard supports more than two IDE channels, I'd recommend setting each drive you have as a Master."

Definately.

Thorin

 

[todpod]

So along the same lines, it won't affect cdrw performance if its on the secondary slave setting as long as I am not copying from the dvd, correct? Have One hard drive, dvd and cdrw. ATI says may the DVD primary if you have choppy DVD play back. thanks todd

 

[Jhhnn]

It's not really much of an issue any more. Modern IDE controllers and bioses usually allow any device to be selected as the boot device, and mixing different speeds on the same cable no longer confines both devices to the speed of the slower one, IIRC.

Writing from one channel to the other is somewhat faster than writing from one device to another on the same channel, but it's not a huge difference. I usually just go along with what the cabling will easily allow, using csel when possible. Why fight it?

 

[thorin]

"Have One hard drive, dvd and cdrw. ATI says may the DVD primary if you have choppy DVD play back. thanks todd "

Best bet is:
Primary Master - Primary HD
Primary Slave - DVD
Secondary Master - CDRW
(BTW csel or cs stands for cable select inwhich the drive at the end of the cable is the master and the one in the middle is the slave [IIRC])

"Modern IDE controllers and bioses usually allow any device to be selected as the boot device,"

True.

"... and mixing different speeds on the same cable no longer confines both devices to the speed of the slower one, IIRC."

Yes that's right all current IDE controllers use independant device timing so you can mix a ATA33 device (CDROM) and a ATA133 device on a ATA133 channel and they will both run at their own best speeds (the ATA33 device will NOT force the channel/other device to run at ATA33).

Thorin