Renard 64 XC Full Power Issue

[smv]

I just built my first Renard 64 XC with all the parts. I am connecting via RS-232 and I have JP1 closed (shunted). I am using Mouser part 41FD030 (3A version) transformer... so everything according to spec.

In Vixen I am configuring a profile for my Renard on COM1, 56700 baud, 8N1 for channels 1-64. When I use the tester I *can* cycle through each channel one at a time and the LEDs will light up.

I also hooked up an SSR I used from last year for my Olsen 595 and could go through each 4-channel ports and dim my lights from 100-0% and back (dang that's cool!). All of the ports work this way too.

My problem is when I turn on all channels in the test or in a sequence. The first 32 work and so do some of the next 32 randomly. That is, I press "unselect all" followed by "select all" and the first 32 come on and some of the next 32 come on.

If I keep pressing "select all" then more of the second 32 turn on... one at a time. Eventually all of them are on.

I have checked my solder joints and everything looked fine. Plus the fact that I can get all of the channels to work one 4-channel block at a time.

Before I hooked up the transformer to the board I tested it with my multimeter and I was getting 7.03VAC on the two red wires.

I am at a loss for what to look at next and any assistance would be greatly appreciated.

Thanks,
Seamus

[dnesci]

I would check the serial port you are using. Most computers today use the com1 port for the mouse. Are you sure your serial port connected to the ren64 is port 1.

[dlovely]

I do not own a Ren64 yet, but I am looking to get one so I did some reading. This statement is what confused me, as it says it is too much for the on board regulator, but then later in the Wiki recommends using a 3A power supply...

Note 1: The on-board regulator should only be used if measures are taken to keep the current consumption down (omitting the on-board LEDs, and using the non-PWM firmware). If the LEDs are used and the PWM firmware is installed, the current consumption of the board is about 1A, and so the regulator will dissipate too much power (the small value of C1 precludes decreasing the input voltage). If you are using an external PC power supply, you don't need these optional parts.

[j1sys]

I think this is a classic case of count those milliamps. If ALL 64 LEDs are turned on then, according to my calculations, you will draw about 500ma just for them. when added to the 8 PICs and the other interface chips you are probably right over the limit of the regulator. If using an external power supply in the 3AMP range you would have a safety margin.

This is usally the case when you see something like this where each individual LED works but the circuit drops out when you turn on all 64.

Each LED is current limited by a 680 ohm resistor so:

5v / 680ohm = 7.3ma

7.3ma x 64 LEDS = 488ma

-Ed

[smv]

The computer has only 1 serial port and the mouse is USB. Vixen only registers that only COM1 is available.

Ed, I'm at a loss of where to begin diagnosing what you're suggesting. Add to that fact that if I continually press the "select all" button in the test screen of Vixen that eventually all LEDs/channels power on.

Seamus

[dirknerkle]

I usually start diagnosing something intermittent like this in a methodical way, but it always starts with cleaning the board of any possible top/bottom leftover stuff from soldering. I use a dry toothbrush and a vacuum.

Then I check over my soldering with a magnifying glass. It's amazing how easy it is to completely miss soldering one of the legs of a DIP socket. Sometimes looking at those shiny solder pads confuses your eyes, so you need to stop at each one. Doesn't hurt to use a sharp object like a dental pick to actually poke at the joint. Don't have a dental pick? Use a long sewing needle or a single strand of cat-5 wire.

Next I usually reflash the pics. I know the one-at-a-time test indicates that it's working, but I like eliminating all possible variables. It takes only a minute and can eliminate a lot of head-banging against the bench...

Next, I check to make sure the computer has a good ground connection. Sounds crazy, but weird things happen with computers if they're not plugged into good electrical power. If it's a laptop, I make sure the power outlet is at least properly wired with hot/neutral. (I have a dedicated computer power line in my workshop, but I still check it periodically with a circuit tester.)

Now I'm ready to re-test the board again.

I try with the same cable I used before. If the problem remains, I try a different cable. If the problem remains, I put a balun on the serial cable and try it again.

If that doesn't work, I go get a couple beers, some popcorn, sit back and watch a movie before I start over again...

[ukewarrior]

This comment is for the XB board.

XC's are different.

Originally Posted by dlovely

I do not own a Ren64 yet, but I am looking to get one so I did some reading. This statement is what confused me, as it says it is too much for the on board regulator, but then later in the Wiki recommends using a 3A power supply...

[smv]

Thank you for all the great suggestions! While I have a dedicated PC for my light show/microprocessor development there seems to be a problem with it. With great difficultly I managed to find another PC with a serial port... works great everytime!

Originally Posted by dirknerkle

If that doesn't work, I go get a couple beers, some popcorn, sit back and watch a movie before I start over again...

Definitely sage advice! I believe I will follow this in celebration!

Thank you once again,
Seamus

[plasmata]

Its amazing how often the problem ends up being caused by one of the last things you would think is causing it. I generally start troubleshooting by swapping out the easy things like cables.