Hi

I would like to know whether or not two connectors(for two hard drives) on the 40-conductor of the 40 pin IDE ribbon cable have the same signal/data from the host controller? If they are different, what line(s) of wire are different on the two connectors? How about the two connectors of the 80-conductors of the 40 pin cable?

Thank you very much

http://www.pcguide.com/ref/hdd/if/ide/conf_Sig.htm

Thank you hiho. I have read that article, but still not sure about the 40-conductor of the 40 pin cable(I thought they are same, but want to make sure). For the 80-conductor of the 40 pin cable, the only difference is the pin #28 on the two connectors. The middle connector of the 80-conductor of the 40 pin cable doesn't have the pin #28 connecting to the ground line. I just want to make sure about this. Anyone who knows well about this, please help me. THank you

I'm sure that 40 wire is straight parallel [pin 1 goes to pin 1 etc]. I worked in a shop where they made custom cables. Just cut 40 to needed length and crimp 'em on.

80 wire is another story.

Keep in mind that DC path is one thing and that impedance is entirely different. The faster the signal, the more impedance is a factor.

M2

If at first you don't succeed, you're about average.

If the system is using cable select then one of the pins (28) is not connected on the 'slave' drive. The 40 and 80 pin cables are opposite. The 40-pin CS master is in the middle.

see:

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

THank you Mechanix2Go and wizard-fred. It is for you Mechanix2Go. Have you ever made a custom cable of 80-conductor for the 40 pin cable with the two connectors go to the drives that have the SAME data line from the source? In addition, do you think that if I use that cable connecting to 2 drives with each drive jumper is set as master, but only ONE drive has the power at the time, do you think the other drive will boost? I have spent so much time to investigate this problem, but I couldn't have the cable that I want because I couldn't find any computer store who made a custom cable. I really appreciate for any helps, suggestions, or ideas.

I have found that if the power is removed from a drive that has the signal cable connected it 'usually' causes major problems with the system. I suggest that you drop your plan and find a different way of doing it.

An alternative might be to leave them connected as Master and Slave. Use the Bios to select which drive to boot from. When you do it this way, the bios makes the boot drive C: and the other drive D:.

My systems are set up this way.

Thank you ham30. I have tried and it works one way. In other words, when the power of one hard drive is turned off, the other drive is able to boost up well(this drive has the "end" connector on the cable), but when I turn off the power of this drive, other drive couldn't boost up, it has a problem to boost up. However, I found a website, http://llamma.com/xbox/Mods/xbox_4_connector_ide_cable_udma_.htm, they made the custom cable for the Xbox, but I think that it also works for the computer. Can you take a look of that link. Thank you very much

"When you removed the power from one drive, the other drive wouldn't boot up"

I think that the fix they have would act the same way.

Have you tried leaving both drives connected to power + signal and going into the bios and selecting each one to boot from it?

If windows has been installed on each drive when it was C:, it should work. If windows has not been installed on the second drive, then just completely disconnect the first drive and do the install on the second drive.

If you want to have just one drive accessible to the system at a time, just enter the bios and disable the one that you want off line.

Disable the drive in the BIOS couldn't boost up that drive only. But when you login into the Windows from the other drive, it can see and is also able to access the disable drive. If I try to partion the master drive, the slave drive is also accessible even the slave drive was set disable. My goal is to make a computer system that runs one drive at a time, and no other drive can be seen. Oh, I didn't quite understand what you said "I think that the fix they have would act the same way." Thank you ham30.

Sorry about that Vien! WinXP ignores the Bios and detects the drives himself, so disabling the drive in the bios will not work.

If you want only one drive available, I don't have an practical answer.

You could purchase a removeable drive bay, which is not a good idea if you are going to be switching a lot.
Or you could switch to Win98. :-)

"I didn't quite understand what you said "I think that the fix they have would act the same way."

I meant that their fix would have the same result as when you physically removed the power from the drive. One drive would not boot.

Oki. I really appreciate your helps ham30. I probably have to drop this plan and try other. Anway, I have learnt a lot about the IDE cable.

oh. After reading your last message again. I am still confusing. So you mean that their system still has the problem?

Their system connects the power to one drive and not the other. I guess it works on the X box, but I don't 'think' it will work on a PC. The IDE controller or the bios might handle that situation differently on the X Box. But I don't really know.

I also cut the power of the hard drive that is not in use. Only the hard drive that boosts up the system has the power. I am also not sure about that. That is why I come here to ask if anyone knows about it. Since it works for Xbox, but not sure for PC. Thank you ham30

It is quite difficult for me to test this out because I couldn't get that kind of cable.

If the only purpose is to boot a drive and see only the partitions on that drive, then if you hide the partitions on the other drive it will not be seen. Probably applicable to Window's only OS's. The best solution is still that of using drive trays. If you want to try the cable way you will have to make your own cable. I would use relays to switch the 'csel' line on the cable and the select pins on the drive. The only possible problem is signal loading caused by the inactive drives.

Hi wizard-fred. Did you mean I should make a switch to disconnect the "csel" line that connects to the "end" connector of the cable and re-connect the "csel" line to the "middle" connector? If that is the case, it might work, but you know that I also have to create an even more complicated cable. I think that I don't need a switch for the jumper on the hard drive.
Oh, I have an alternative plan for my current plan, but I want to have some opinions from you guys before I go to test. If I use the Secondery IDE host controller to control the second hard drive (assume that I don't need to install CD/DVD-ROM drive) with a power switch to control the power of the primary(master) hard drive and secondary(also set as a master) hard drive. Will it be able to boost up from either drive?

THank you so much guys. I really appreciate your helps/ideas

Alternately powering the drives on different channels should work providing the boot select in BIOS doesn't cause any problems.

Actually I was thinking of enabling 'csel' and turning on the power at the same time and by having more than 3 connectors on the cable.

yes. :) I have just test to boot the second hard drive(set as master) on the secondary controller without modifying the BIOS while the power on the other hard drive was off. It boots up fine. Then I also tried to boot the first hard drive (set as master) from the primary controller, and it works fine.

I am also very very interesting with the solution to create a custom IDE cable with ALL connectors have the pin#28, plus a switch to select the "csel" signal for the pin#28 of the connectors on the IDE cable. In addition, this solution also needs to make a power switch for selecting the hard drives that need to boot up.

Hi wizard-fred. Are you sure that the "middle" and the "end" connectors on the 80-conductor of the 40 pin IDE cable is only different on the pin#28? The rest of the lines are same?

Thank you very much for any helps

I have not made an 80-wire IDE cable. I only use the M/S configuration. The 40-wire cables I make are straight thru with all the same connectors.

In regard to addressing you might be able to also use pins 37 and 38 (the documentation is a bit sketchy).

Separating out the conductor from the ribbon cable takes a steady hand and a sharp razor, followed by reasonable soldering ability.

I am a little confusing your message. Did you mean that you have tried with the 40-wire cable with all connectors have the same data lines? Does it work when you unplug the power of one hard drive and boot up the hard drive and via versa?
Sorry for my poor Egnlish, I didn't know what you mean "In regard to addressing you might be able to also use pins 37 and 38 (the documentation is a bit sketchy)"?
If this soluton works, it is great.

However, I am also thinking to buy a RAID controller card(may be about $20) that supports 2 channels, so that I can add two more hard drives, each one is on its own channel. So in the total, I can boot one out of 3 hard drives, right?

For the current 40-wire of the 40 pin IDE cable on the market, the two connectors to the hard drives also have a different data lines?

I am really appreciative your help wizard-fred. Sorry for the long message

Most of the 40-conductor cables I have are straight thru. And it doesn't matter which connector is used where. And if they are not keyed, they can be used rotated 180. The newer better cables have had pin 20 plugged. I have not given any of the 80-conductor ones a detailed examination. I haven't tried playing with the boot sequence.
I use only the Master and Slave configuration.

Pins 37(cs1) and 38 (cs3). CS channel select or chip select. There was a reference to the action with regard to master and slave. Further research is needed.

In regard to using an addon IDE controller. To be bootable it has to be recognized by the BIOS. Some early ones require a driver, since they use alternate IO ports. (These would not be bootable.) Later ones like the RAID you mentioned probably have some form of extended ROM BIOS on the board.

Thank you wizard-fred. I am looking at this controller card "Promise Ultra133 TX2 2-channel Ultra ATA/133 Controller". I don't know whether it has driver or not, but I think that it is not a RAID card. Here is the link to this card of the Promise website, http://www.promise.com/product/product_detail_eng.asp?segment=Non-RAID%20HBAs&product_id=87 or http://www.promise.com/product/pdquide_eng.asp

Can you please tell me if it works in my case or not? Thank you so much.

This is the onboard BIOS from the specification of this card.

onboard BIOS:
Auto-identifies and configures drive type; auto-detects and supports Ultra Mode transfers; easy conflict-free installation

OK. You have an onboard BIOS that configures the drive. Now the only problem is does the regular BIOS allows booting from the attached drives. You may have to buy it and try it. I know nothing further.

Thank you so much wizard-fred and anyone who has provided helps, suggestions, or ideas to me. I really appreciate your help, wizard-fred. I have to go to buy this card and try it out. I hope that it works. Otherwise, I have to continue to find a different solution again.