View Full Version : Olson 595 channel shift problem

04-08-2009, 12:46 AM
I just built a fully-populated 595 using the co-op board and while all 64 channels light, I have a weird problem with channel 40-41. I build the board using red, blue, yellow and green LEDs which match light string colors, and everything is in sync just fine through channel 39 (yellow). However, channels 40 and 41 light up together (green & red) instead of individually, and from there on, the channel numbering is off by one, resulting in only 63 channels available -- although selecting "ALL" in the Vixen test lights all 64.

I have thoroughly checked my soldering (I'm a fantastic solderer) and can't find any soldering/trace problems anywhere. I thought it might have been a bad chip so I exchanged chips all over the board -- the problem remains at 40-41 so it appears that the chips are okay.

Could it be the parallel port or some other anomaly I'm not seeing? I'm using an old Dell 2350 -- 1.8mhz celeron, or could it be a Vixen issue??? I'm new to the Olson 595 but not new to electronics at all... Any ideas out there?

04-08-2009, 09:16 AM
Try changing the port settings when you boot up. EPP usually works, but try them all if it don't.

04-08-2009, 11:22 AM
Apparently when using Parallel port the voltage from PC printer port must be close match to the power supply to the 595 board, I had the same problem and this can be cured by either placing a resistor in power line to the board or, I chose to place doides in power line. By some REN-Cs for a serial connection much better ! then you,ll have dimming . JK

04-08-2009, 11:35 AM
I'm quite grateful for the quick feedback - thank you very much!

I'll try the port settings first (I believe the port is set to a "standard" mode at present) and if that doesn't effect a cure, I'll check the board's input voltage vs. the port's voltage. The board's power comes from the PC using one of the 5v outputs intended for disk drives.

I've toyed with the idea of the Renard and I think I'll order 3 kits as part of the co-op... that would give me a total of 248 channels and no possible way to pay for the electricity to power the lights!

04-09-2009, 12:28 AM
Progress update...

WakeFan's suggestion to change the port mode to EPP did the trick. The port was set in bi-directional mode. Now the 595 works as intended -- all the channels function properly.

I'm very impressed with the helpfulness of the folks here. I hope that I'll be able to contribute as time goes on and that my comments are found to be as helpful as those I've received.


04-09-2009, 11:16 AM
Good to here your up and running, I think the Admins will agree posting your "cure" helps us all in the "Blinky" run.