What does Master and Slave mean and what is the difference? (1 Viewer)

SoCal

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Hello everyone, I have always wondered what these two connections mean and what the difference between them are. Also which should be connected to master, CD Burner or CD ROM? Thank you for any help:).
 

Soliah

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http://www.pcguide.com/ref/hdd/if/ide/confJumpering-c.html

Note that despite the hierarchical-sounding names of "master" and "slave", the master drive does not have any special status compared to the slave one; they are really equals in most respects. The slave drive doesn't rely on the master drive for its operation or anything like that, despite the names (which are poorly-chosen--in the standards the master is usually just "drive 0" and the slave "drive 1"). The only practical difference between master and slave is that the PC considers the master "first" and the slave "second" in general terms. For example, DOS/Windows will assign drive letters to the master drive before the slave drive. If you have a master and slave on the primary IDE channel and each has only one regular, primary partition, the master will be "C:" and the slave "D:". This means that the master drive (on the primary channel) is the one that is booted, and not the slave.
Just pick whichever for your burner and CD-Rom. Doesn't matter.
 

Huy

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Originally posted by Merethrond
I have always wondered what these two connections mean and what the difference between them are.
* Each IDE/ATA channel can support either one or two devices.
* IDE/ATA devices of course each contain their own integrated controllers, and so in order to maintain order on the channel, it is necessary to have some way of differentiating between the two devices.

This is done by giving each device a designation as either master or slave, and then having the controller address commands and data to either one or the other.

Note that despite the hierarchical-sounding names of "master" and "slave", the master drive does not have any special status compared to the slave one; they are really equals in most respects. The slave drive doesn't rely on the master drive for its operation or anything like that, despite the names.

* The only practical difference between master and slave is that the PC considers the master "first" and the slave "second" in general terms.

For example, DOS/Windows will assign drive letters to the master drive before the slave drive. If you have a master and slave on the primary IDE channel and each has only one regular, primary partition, the master will be "C:" and the slave "D:". This means that the master drive (on the primary channel) is the one that is booted, and not the slave.

* Devices are designated as master or slave using jumpers, small connectors that fit over pairs of pins to program the drive through hardware.

Each manufacturer uses a different combination of jumpers for specifying whether its drive is master or slave on the channel, though they are all similar. Some manufacturers put this information right on the top label of the drive itself, while many do not; it sometimes takes some hunting around to find where the jumper pins are on the drive even once you know how the jumpers are supposed to go.

Jumpering information is always available in the manual of the hard disk, or by checking the manufacturer's web site and searching for the model number.

Originally posted by Merethrond
Also which should be connected to master, CD Burner or CD ROM? Thank you for any help:).
* ATAPI devices such as optical, Zip and tape drives are jumpered in pretty much the same way as hard disks. They have the advantage of often having their jumpers much more clearly labeled than their hard disk counterparts.

Most optical drives, for example, have three jumper blocks at the back, labeled "MA" (master), "SL" (slave) or "CS" (cable select).

If you are using two drives on a channel, ie CDRW and CDROM (or HDD) it is important to ensure that they are jumpered correctly. Making both drives the master, or both the slave, will likely result in a very confused system.

Note that in terms of configuration, it makes no difference which connector on the standard IDE cable is used in a standard IDE setup, because it is the jumpers that control master and slave, not the cable. This does not apply when cable select is being used, however.

My recommendation:
Primary Master: HDD #1
Primary Slave: CDRW
Secondary Master: HDD #2 (if you have one)
Secondary Slave: CD-ROM/DVD-ROM

It does not matter (see above). If you have 1 hard disk, then leave that as your primary master. If you have 1 hard disk, CDRW AND a CDROM, then:

Primary Master: HDD
Primary Slave: CDROM
Secondary Master: CDRW

They are just recommendations, but if it works for you, it works for you :)

Edit Soliah beat me to it since I was fancying it up :)
 

SoCal

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Thank you both for your help. I have always thought that my burner should be set to master but I really had no idea. I have no idea what my hard drive is set too, I will have to have a look at that. Also, how do I get secondary master and secondary slave? Also, you have got me interested in what cable select means. Thank you very much again for your information and help:).
 

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The very first line of my post alluded to more than one IDE/ATA channel on your mainboard.

You have two IDE channels, primary and secondary.
Depending on the board, they will be located in the same spot, so you will know (they are labelled IDE1 and IDE2).

Most optical drives, for example, have three jumper blocks at the back, labeled "MA" (master), "SL" (slave) or "CS" (cable select).

If you are using two drives on a channel, ie CDRW and CDROM (or HDD) it is important to ensure that they are jumpered correctly. Making both drives the master, or both the slave, will likely result in a very confused system.

Note that in terms of configuration, it makes no difference which connector on the standard IDE cable is used in a standard IDE setup, because it is the jumpers that control master and slave, not the cable. This does not apply when cable select is being used, however.


Cable select does not require jumpers to be appropriately fixed/located in the master or slave position, you can leave it on CS and it'll decide for itself (the location determines master/slave). It is the cable which decides if it is a slave or master.

Here's what you should do,
* Read your motherboard/mainboard manual and familiarise yourself with the type of board you have.

* Take a good look at the components inside your chassis.
* If you're unsure, don't touch anything.

If you know what you're doing, you could unplug every IDE device (be it an optical or hard disk) and re-arrange everything accordingly (see slave/master and jumper settings as well).

If your device is set to 'CS' (cable select), then whatever it is connected to (be it master or slave) will be determined by the device's location on the cable, not the jumper itself.

So you might have a system which looks like:


MOTHERBOARD ---------- IDE1 ------ CDROM --- HDD1
|
|
|
IDE2 -------------------- CDRW ---------------- HDD2

(Please note, IDE1 is your primary IDE channel, working it's way out from your mainboard to the "end" device goes: mainboard -> slave -> master)

So in the above diagram,
On the primary IDE channel, you have two devices.
Your primary (C:\) HDD will be the primary master.
Your CDROM will be the primary slave.

On IDE2 (secondary IDE/ATA channel),
You have, again, a HDD acting as the secondary master, and a CDRW being the secondary slave.

If each device is jumpered to cable select, then you can mix and match (on any IDE channel, one can be the master one minute and replaced to become the slave in the next, without changing jumper settings).

:)
 
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Soliah

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Ok, Huy, I read what you said but you lost me :O

So I'm going to give explaining cable select ago.

If you set your jumpers to cable select on any IDE device, where it is connected to the cable will determine if its a Master or Slave.

A IDE cable will have 3 heads, one to connect to the motherboard and 2 others to connect to devices. By selecting cable select, you don't need to worry if both drives on the same cable are both master or slave - where it is on the cable decides what it is.

So if you set both your CD-Rom and burner on cable select, then place your burner on the end head, the CD-Rom on the middle head, then your burner will be master, and CD-Rom slave.

Here is some info on setting up your drives in Cable Select.

You have 2 IDE channels, a Primary and Secondary. These are most likely called IDE1 and IDE2 in your motherboard manual. Your Secondary Master and Slave are the 2 devices on your IDE2 channel. Simarly, your Primary Master and Slave would be on IDE1.
 
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Huy

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I'm trying to apply what Mereth knows, with his/her own situation (knowing that there is at least one HD, a CDROM and a CDRW)

But what you said is a general explanation and will answer his/her queries. I like to answer questions based on the scenario.

What you have said is correct :)
I just wanted Mereth know that he/she can figure it out by understanding it and seeing the devices first-hand, instead of reading it verbatim.

Either way, I'm sure Mereth will understand.

Pictorially,

. . . . . . MOTHERBOARD . . . . . . <== your board
. . . . . . . . . . . . . . . . . . . . . . . . .
. . IDE1 . . . . . . . . . . . IDE2 . . . <== your 2 IDE channels, IDE1 (primary) and IDE2 (secondary)
. . . | . . . . . . . . . . . . . . . | . . . . .
. . . | . . . . . . . . . . . . . . . | . . . . .
SLAVE . . . . . . . . . . SLAVE . . . . <== prim. slav and secondary slave respectively
. . . | . . . . . . . . . . . . . . . | . . . . .
. MASTER . . . . . . . . MASTER . . . <== prim. mast. and prim. slave
. . . . . . . . . . . . . . . . . . . . . . . . .

When any device is set to CS, you can shove them anywhere and it'll sort itself out according to its position on the IDE channel.

If you have a device set to MASTER, then it'll only work if it's at the end of the IDE cable.

Similarly, if it's SLAVE, the same applies (in the middle).

I hope Mereth gets it now :)
 
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SoCal

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Thank you both so much for all your help. I understand everything quite clearly now:). When I get off the computer, I will have a look at all my conections and let you know how I went:).
 

Huy

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Originally posted by JRasnier
hehehehe now huy explain raid..... :p just want u to type somemore...
:rolleyes:

I'm busy with my Major Work hehe ;) :p
 

Jeo

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well done Huy.... the poor guy hasn't been back for more than a week! ahhahahahaahhahaha :lol:
 

Huy

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LOL.

I'm sure Mereth is around somewhere...maybe just not in the IT stuff forum (sorry!!) :)
 

Jeo

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wtf are you feeling sorry for man! youre the man! WELL DONE! THATS THE WAY! I WISH I COULD DO THAT! YEAH! :lol:
 

Huy

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Originally posted by Soliah
And that's all I'm typing up :p
Way to go Soliah :)
I was thinking about typing it all, but ... nah!

I'm going to eat, lol :D
 

SoCal

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Originally posted by Merethrond
Thank you both so much for all your help. I understand everything quite clearly now:). When I get off the computer, I will have a look at all my conections and let you know how I went:).
Sorry I took so long everyone, I have been kind of busy:). My CD burner is connected to secondary master with my DVD player connected to secondary slave. My hard drive is connected to the primary IDE slot but I cannot see what jumper setting it is set to and I do not really want to unplug it for no reason, in case I break it:).
 

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