Link to home
Start Free TrialLog in
Avatar of mauryg
mauryg

asked on

daisy chain on parallel port

I have three peripherals attached to my parallel port.
#1 Syquest removeable hard drive(for backups)
#2 SCM compact flash card reader(for digital camera)
#3 HP 660Cse printer
Each item works fine when attached all by itself.
The middle item is not recognized when all three are daisy chained together.
The printer is always last and I swap the card reader and
removeable drive back and forth from closest to the computer
to second in line.
I have a Pentium computer with Windows 95
mauryg@starlinx.com
Avatar of G0LIATH
G0LIATH

Install another Parallel port, I think you can only have one passthrough connector per port.
Not all passthru paralell ports are able to use ECL, EPP, or Bi directional.
Check with the manufacturer of the attactments.

Is your parallel port set for EPP or ECP? I would suggest that you set it for ECP. That is done in the BIOS.

If you are using the standard parallel port, and are daisy chaining, the port may not have the responce time to see all 3 devices. Therefore, it will skip the least important one (that being the middle device).

Also, check the cables. Switch them around, as well.

Let me know
How does it go if only 2 devices are connected?  I think most daisy chainable items dont provide full support for ecp or epp on the output... so you cant daisy chain more than two items.

(otherwise the middle item is not getting epp/ecp)


That is a good question. What happens if you only connect 2 devices?

I have a Zip drive, Scanner, and printer, and I can access all three if connected together on a ECP port. I believe that you can have up to 5 devices connected to the Parallel port, as long as the cables are not too long (3-4 feet between devices).

a Parallel port is a weak port to begin with. It was never intended to connect some of the higher powered devices that is connected. ECP and EPP were made for devices that needed more throughput at higher rates.

It is also not recommended to run more than one device on the chain at the same time.

Nonetheless, if you have read that EPP and ECP do not support more than two devices, then I would like to see the documentation that you read that from.

Let me know.
Avatar of mauryg

ASKER

Thanks so far, but nothing has worked. the parallel port  is set 378H  default
                                                                     other choices=3BCH
                                                                                           278H
                                                                                           Auto
                                                                                           Off

      The parallel port mode is set on    ECP  high speed
                                      choices are   PS/2
                                                        AT =  output only
I have removed the printer and tried just the two and only the card reader works.
I won't give up if you won't. Thanks for the help..
                               

If you do not need to access all the devices at the same time, you can try an A/B switch, usually available at any electronics or computer parts store.  It's probably a little cheaper than buying a new parallel port card.

Regards,
Jeremy
Your settings are fine.

I am curious as to what would happen if the second device is the printer, and the first device is either the syquest or the card reader.

Next: go into windows, and try removing all three devices from the device manager, then the printer port. Let windows redetect it. Were there any question marks or Exclaimation points in the device icon?

Finally, are there any .ini files that either the syquest or the SCM made on your computer? I am looking for settings (or more specifically conflict of settings).

Let me know
Try changing your parallel port mode to EPP if you haven't already done so; some devices may not be compatible with ECP.

-JPC
Avatar of mauryg

ASKER

I can't make the printer first or second in line because there is no pass through port on the printer.  A/B switch can't be used because the card reader and the Syquest drive must be seen by the computer at boot up.
The simplest solution will be to add an additional parallel port. (or two)
They are inexpensive, and will solve the problem that you are experiencing.
Regards,
Ralph
yeah, I didn't think of that fact (that the computer needs to see some devices at startup to load the proper drivers).  I think the best solution will be a second parallel port - it will improve performance on all your devices anyway, especially if you place the removable drive on its own connector, and daisy chain the printer to the scanner.

-Jeremy
if you set up electrical shut off on each device and only have two on at load[turn on computer] they will work. a 2nd parallel port will work until you crash,then you lose all the special code/setup data. also with 2nd port you have irq etc problems. use a parallel port that addresses advanced irq 10-15 i think. it is more expensive and you probably have all irq used anyway.

i have 5 parallel devices and two computers and a a/b box. i control eith aux electric switches. printer is on own line as it has a special shutdown sequence[all ink jets][cant be turned on/off with computer or will fail][clb4aces@netzero.net]
clb4aces,
That may be the solution to your problems.....
not necessarily the "answer" in this case.

An add-on bi-directional parallel port adapter can be found for $10-15. (To me, that's inexpensive if your time is worth anything)
They will use either IRQ5 or 7, and will co-exist with other devices just fine.

maury,
We need some feedback from you.
If you accept the proposed "answer" by grading it, the question will be closed, and your points awarded at that time.
I suggest you reject it if you find that it doesn't solve your problem.
This thread can then continue with other experts contributing their suggestions.

Ralph
Avatar of mauryg

ASKER

The electrical (switch) shutoff idea on each device is more difficult than it sounds. The card reader
uses a electrical connection that plugs in to an adapter that connects to the PS/2 opening .This plugs into a port(connection) in the back of the plug that is inserted in the parallel port.
The removable disk drive (Syquest) uses a five conductor cable that goes to a transformer.
The transformer plugs in to the wall. Both cables are three feet long, the printer cable is six feet long. When I removed both devices in device mgr. and reinstalled ,I got no errors
or symbols showing up.With all the changes I have tried, nothing has changed.
I think I will have to go with the second parallel port idea.
When I connect only two devices ,only the first one works.
Avatar of mauryg

ASKER

STOP! I quit...I will take the advice of Goliath who was first with the suggestion and rmarotta who was second with the suggestion to buy a second parallel port.
Thanks guys
Avatar of mauryg

ASKER

who distributes the points        who decides who gets what?
You do.

If you want to split the points, just go to the Customer Service topic area on the home page.  Post a zero-points question there and ask the staff for help with doing what you want.

Regards,
Ralph
electrical switch meant unplug from wall
Avatar of mauryg

ASKER

In all fairness... Goliath should get half the points because he was first with the answer that I finally accepted andthe other half to jmarotta because he also gave the same answer I chose as a solution. Thanks to all of you.
Mauryg
I am sorry to hear that you have given up on your question. I know this can be frustrating, and the 2nd parallel port is a good workaround.

Just to clarify my previous comment, I was wondering what would happen if there were only 2 devices, the second one being the printer. You do not need to "pass it through", because I was curious to find out if the printer was unrecognizable as the second device.

Nonetheless, good luck, and I;ll keep an eye on this thread if you would like to explore it further.
Avatar of mauryg

ASKER

To j_powers,
Thanks for your input I appreciate it.
I tried disconnecting theSyquest drive and attached the printer in its place and the printer does not work. In all fairness I may have screwed up something else. Its going to take me awhile to reset everything. Thanks again
Maury
mauryg:

If you need anything else, just ask, although I think the second parallel port will solve your problem just fine.

Regards,
Jeremy
ASKER CERTIFIED SOLUTION
Avatar of G0LIATH
G0LIATH

Link to home
membership
This solution is only available to members.
To access this solution, you must be a member of Experts Exchange.
Start Free Trial
Avatar of mauryg

ASKER

I would like to SPLIT the points and give Goliath 200 points for first answer
I would like to give rmarotta 100 points for the same answer which made me decide to
go the route you both suggested. I don't know for sure that it will work but I AM going to try it. Thanks, I have to go out and buy the part now.
Mauryg
Mauryg,
See my comment of Friday, January 15 1999 - 12:18PM PST before you grade this question.
Ralph
Avatar of mauryg

ASKER

Its now eight months later and I never solved the problem.  I took the computer to a professional  computer repair place and they couldn't get the second parallel port to work. They charged me and then gave up and gave my money back . I'm back where I started. I use my Syquest drive along with my printer that is plugged into the back of it, ) and they work fine.   When I have to use the card reader, I have to unplug the Syquest drive from the computer and plug the card reader in and if I have to use the printer while this is setup, then I have to take the printer cable and plug it in the back of the card reader.I also have to reboot to be recognized. It is troublesome this way but it  DOES  work. A funny thing happened, I have a USB port too (unused) so I ordered a USB card reader and it did not work , because my
edition of Windows 95 did not have the latest upgrade. c'est la vie.
Thanks again guys.
i cant daisy chain on mine. i have 3 parallel ports with a scanner,brother 7160 mfc, and zip drive. i have each on its own off/on switch and turn on before i boot if going to use. the scanner is usually off. i set the series port[on mb] as disabled in bios.that gives me a irq for third port.
does your bios have  usb. most didnt 3 years ago. the win9x upgrade sites should give you usb. i would reccommend the zd net version of ie 5.0 as best choice to upgrade. win98 ver 2 causes too many programs too need a upgrade for me to use it. i couldnt go back from it and get programs too work,i had to reformat/reload win98 ver 1.