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jeffathompson
06-25-2008, 07:40 AM
Grinch Problems: I have 5 Grinches. They had MBI chips and wouldn't work. Checked and the port was only 3.5 volts. Too low. Got Allegro chips. Grinch works fine. Tested each one, one at a time using a remote power supply plugged into the board, not through rj45. Each worked and ran a 64 channel test sequence.

Time to hook up second board. Hooked up rj45 out on first board to rj45 in on second. Power led lights. Make a 128 channel sequence and seems to run alright although I do get an occasional very dim flicker in the test bulbs from other channels. Really have to be watching close to even see it. I figure using just one 3 watt bulb I'm getting just a stray signal. Up to this point I can also use the test channel panel in Vixen and turn any channel on and off with one click. Looking Ok.

Plug the third board in same way. Short cat 5 from out on board two to the in on board 3. Power LED lights. Here is where it gets fun. The first board, 1-64 runs fine. On off with a Vixen sequence or on off in the test window. Board two gets weird. Run a vixen sequence and they go on off. Appear to be working. Try to use the test panel, I have to click "on" twice to get any channel 65 - 128 to come on. Then I have to click twice to get them to go off. Or get this. If I click on once, nothing. Then click off, the channel comes on. Then I click off again, and it goes off.

On board three. Nothing. Will not run with a sequence or the test panel. Again, this port only has a 3.5 volt output and I had to use the Allegro chips to make it run.

I guess I need direction. I can see it one of three ways.

1. (easiest) The Grinches are not getting enough power and need each to be plugged in directly to the power supply, not power daisy chained.

2. I am somehow setting something wrong in the Olson 595 plugin in Vixen when I go to use 3 boards. (I would like to use 5)

3. Something is set wrong in the Parallel port setings. I have not set any addressing or made any changes to this port. Just wiped the computer clean and put a clean XP image on it. Only things have been installed are two PCI DIO 96 cards, USB wireless dongle. No printers, scanners nothing else that should change the port setting.

If it is #2 or #3 I need help setting them. In Vixen I probably could figure it out. Bt to change the port settings, well I've never done that.

Thanks cuz I know some of you have seen similar before and save me many hours of research. I have read the WIKI and searched this forum but don't see these addressed specifically.

RJ
06-25-2008, 08:04 AM
Sounds to me like you are running a boarderline port and with the extra load on the data lines you are not getting soild singnals. Try a different computer to verifiy and maybe if you have a slot buy on of the $19 add on par port cards they seem to work fine at least the ones I have tried.

I think the low port voltage is the problem if you had to switch the chips to get it to work at all you are on the edge and at any length of feed you are likely to have the same issues with even one of them.

RJ

RavingLunatic
06-25-2008, 08:50 AM
Jeff,

As RJ stated, you are most likely experiencing one of the drawbacks to the parallel port designs. If you have a weak parallel port you can't expect to run multiple boards without some kind of help to the signals.

One of the easiest ways to help out the parallel port signals is to pass them thru a hex inverter first (Thanks to D.Fansler for the idea). Something like 512-74ACT04PC should work fine.

Macrosill
06-25-2008, 11:33 AM
Would a line driver help?

jeffathompson
06-25-2008, 11:47 AM
Thanks guys, I feared that was the problem. I do have another machine I will try my Grinches on. Also, what do you think about just adding a Parallel card?

jeffathompson
06-25-2008, 11:51 AM
Jeff,

As RJ stated, you are most likely experiencing one of the drawbacks to the parallel port designs. If you have a weak parallel port you can't expect to run multiple boards without some kind of help to the signals.

One of the easiest ways to help out the parallel port signals is to pass them thru a hex inverter first (Thanks to D.Fansler for the idea). Something like 512-74ACT04PC should work fine.

And how would this be done.

RavingLunatic
06-25-2008, 12:08 PM
I have an image that would help but I can't upload from work (damn firewalls :mad: )

But basically you bring in a signal (lets say Data) into pin 1 of the chip, jumper pins 2 & 3 together and now the signal comes out on pin 4.

The second signal (lets say Clock) goes into pin 5 of the chip, jumper pins 6 & 9 together and now the signal comes out on pin 8.

The third signal (lets say Strobe) goes into pin 13 of the chip, jumper pins 12 & 11 together and now the signal comes out on pin 10.

The resulting signals would be then have the HIGHs at whatever you used as the VCC voltage (presumably 5 VDC).



Brian - Yes, a line driver would achieve the same thing.

jeffathompson
06-25-2008, 02:15 PM
I have an image that would help but I can't upload from work (damn firewalls :mad: )



Work does get in the way of Christmas lights. I have such slow dowloads on my laptop that I have to type one handed while holding on to the steering wheel with the other.
LOL yes I can surf the net in the car on the Sprint card while talking on the phone through the navigation system.

only thing I did not understand is where the +5v comes in.

RavingLunatic
06-25-2008, 02:38 PM
only thing I did not understand is where the +5v comes in.

Sorry, made an assumption there, thought you might have taken a look at the datasheet for the chip:

Pin 7 = GND, Pin 14 = VCC (5 VDC)

Wayne J
06-25-2008, 05:25 PM
So, looking at this IC, the signal gets inverted twice, so it is the same out as it was going in, just amplified, correct?

RavingLunatic
06-25-2008, 06:41 PM
So, looking at this IC, the signal gets inverted twice, so it is the same out as it was going in, just amplified, correct?

Not really "amplified", more like "pulled up" to the VCC. The chip I mentioned, will treat any input above 2 VDC as a high then it will output it (after the double inversion) at the VCC of the chip.

Like Brian mentioned a line driver would do the same thing just without having to invert it. The line drivers I have are 20 pin chips so the hex inverter method uses a smaller chip. Many ways to skin a cat.

jeffathompson
06-26-2008, 07:13 AM
Well I fired up the Sony that I have as my backup light computer. It does have 5.5 volts at the parallel port. I set up new sequences for one, two and three Grinch's. One runs fine on any set of chips. Two runs fine on any set of chips. Three runs intermitantly. Turn all on, they all turn on and off with one click. Turn the particular channel on or off. Some work some don't. Some sets of 4 I would turn one on, nothing, turn the second on, both would light, turn the first off the second stays on and can turn that one on and off with one click.
So it is intermitant at best. It appears that two Grinch's is the limit.

I would be thinking that if I used theHex Inverter method to boost voltage, I would be best to put one in between each Grinch. That would work correct.
I have plenty of open slots so I may just add two Parallel port cards but then that opens a whole other can. Getting them all addresses.

Why didn't I listen to mom and become a missionary

RJ
06-26-2008, 11:28 AM
That problem sounds a lot like the old port setting in the bios not right probem. We saw that kind of issues with the 595's and Grinches when the port settings in the bios were on the wrong type of port. Can't remeber which was right and I think sometimes it depended on the machines. So try EPP and ECP setting both to see if it work on this machine with both settings.

RJ

jeffathompson
06-26-2008, 02:46 PM
That problem sounds a lot like the old port setting in the bios not right probem. We saw that kind of issues with the 595's and Grinches when the port settings in the bios were on the wrong type of port. Can't remeber which was right and I think sometimes it depended on the machines. So try EPP and ECP setting both to see if it work on this machine with both settings.

RJ

Looks like it's time to read up on parallel port setting. Oh well, one more thing to learn.

RJ
06-26-2008, 08:58 PM
If it is intergrated port on the motherboard you should find the settings in your Bios and just change them there. Try each and see if one works for you.

RJ

RPM
06-27-2008, 12:15 AM
So, looking at this IC, the signal gets inverted twice, so it is the same out as it was going in, just amplified, correct?

Yes, that's the basic idea. You could also use a 74HC14 inverter as well. This is a Schmitt trigger type, which will help a little by adding a little "deadband" to the input trigger levels and will have a much cleaner output.

Another thing you can try is install an add-on parallel port card to your computer and run the Grinches off this. It may be the cheaper and easier solution.


Robert

jeffathompson
06-27-2008, 04:01 PM
Yes, that's the basic idea. You could also use a 74HC14 inverter as well. This is a Schmitt trigger type, which will help a little by adding a little "deadband" to the input trigger levels and will have a much cleaner output.

Another thing you can try is install an add-on parallel port card to your computer and run the Grinches off this. It may be the cheaper and easier solution.


Robert

Being completely obsesive compulsive I ordered two PCI port cards for like $9 each AND I ordered Hex Inverters AND sockets AND am in the process of drawing a board to etch for these. So I will be able to do this thing about 6 ways HE HE HE !!!!!! (plus I changed the OLN board a little and am redoing that.) You guys are in a lot of trouble with my wife for getting me hooked on this stuff.