I just helped my friend install an internal cd-rw drive last night. The instructions suggested to set the drives master/slave settings as necessary. As this computer is a Compaq, the manual was completely useless. The original cd-drive was set to the cable select setting, so I set the cd-rw drive to that as well. This didn't seem to work so I made the original cd drive master and the cd rw drive slave. That allowed it to work.
I have 2 questions. What exactly exactly does master/slave mean? (I have an idea, but not enough to explain it and I figure someone here can.)
Also, how do I hook up both drives to the sound card? Each has an audio out and the card has one audio in. Does it require 2 cards? Is there a splitter cable available? Am I sool? He really doesn't care if the cd-rw drive goes through the card, but I like to leave this fully operational.
-Thanks
<FONT COLOR="#000000" SIZE="1" FACE="Verdana, Arial">[This message has been edited by jourgenson on March 05, 2001 at 10:59 AM]</font>
With any drive interface, the computer needs a method by which to distinguish and prioritize the drives on a channel. With SCSI, you can have up to 8 devices, including the controller, on a channel, so SCSI uses a numerical ID system. IDE only allows 2 devices per channel, so the best way to use this is for one to have priority over the other, hence the master/slave designation.
The master drive will get priority over the slave, so it's recommended that you put the CD-RW in as master to minimize the possibility of buffer underruns.
The most common method your friend will be writing files to CD-RW will determine how you want to configure the drives in the system.
If he's planning on making a lot of CD->CD burns, I would recommend that you set the CD-RW as master, and set the CD-ROM as slave, and put the CD-ROM as a slave to the hard drive, with the CD-RW on it's own channel.
If he's planning on making a lot of hard drive->CD burns, have the hard drive as master on one channel, the CD-RW as master on the other channel, and the CD-ROM as slave to either of those.
As for your second question, if the sound card only has one channel, just use the CD-ROM to play audio discs. If you're not playing audio from the CD-RW, you don't need to hook it up to the sound card at all.
I don't think you'd be happy with the sound quality you'd end up with if you used a splitter, if one even exists for this purpose.
You could always get another sound card with more than one CD audio input. I know that the entire Sound Blaster Live series has up to 4 inputs on the card, and the Creative Labs Ensoniq AudioPCI has additional inputs. It's a decent basic card and can be found just about anywhere for about $30.
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"It's always funny until someone gets hurt, and then it's just hilarious."
An IDE controller is capable of controlling two devices. The master and slave. The slave device operates off of the master...meaning, when you access the slave device, you are in essence accessing the master. It's pretty much as simple as that. The two devices operate at the speed of the slowest device, and when the two devices are being used, they must share the bandwidth of the IDE channel. I think it uses time division multiplexing. So, as you can see, running more than one device per channel WILL slow you down on IDE.
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Does driving a car from Saturn make me an alien?
That which does not make me barf, makes me stronger - possum37, fugly.net guru.
Not true, because a limitation of IDE is that it can only access one device per channel. So, they're not sharing, but rather, one device has control of the channel at any given time when they're in use. This is where the priority comes in. If both devices are in use, the master gets the priority. When it's finished with it's task, the control gets passed down to the slave device.
The main advantage of SCSI over IDE is that SCSI can simultaneously access all devices on a channel. While there still is priority when dealing with SCSI, it's hardly the same issue as IDE.
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"It's always funny until someone gets hurt, and then it's just hilarious."
I stand corrected. Interesting to learn this....this makes it quite possible that the slave device won't get accessed if the master is always getting used?
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Does driving a car from Saturn make me an alien?
That which does not make me barf, makes me stronger - possum37, fugly.net guru.
A device wouldn't quite dominate the channel to that degree. The end-user would notice it more as decreased performance.
When doing a CD burn, giving the CD burner the lower priority will usually result in the data not being fed to the drive fast enough to fill the buffer, the buffer will empty, and the burn will fail because of a buffer underrun.
This obviously won't always be the case, but is dependant on the type of burn being done.
Ideally, one could put every IDE device by itself on it's own channel so priorities wouldn't be an issue and performance would be at it's peak efficiency. However, with each IDE controller requiring an IRQ, and most systems only having 2 controllers, that means one is limited to 2 devices for peak efficiency. If you add in one more device, you run into all sorts of possible issues.
If you're going to have 4 or more devices, it's generally recommended that you go SCSI.
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"It's always funny until someone gets hurt, and then it's just hilarious."
