Each controller can drive up to 40 unique outputs. RGB LEDs take three
outputs on the controller instead of one.
There can be up to four controllers connected together. There are jumpers
on the board that determine which of the four it is. I will include two
parallel port cables if two boards are ordered. The user will have to cut
the end off the second cable that would normally attach to the computer, and
attach the ends of that cable to the parallel port connections of the first
board. If desired, I can do that mod for the user.
There are 17 levels of brightness; zero plus 16 different levels of current.
Yes. The RGB LEDs must be common anode, NOT common cathode. Supported
RGB LEDs will have four legs, one for each of red, green, and blue, and
one for the common anode.
There are 17 levels of brightness, so 17 * 17 * 17 = 4913 different colors.
The controller connects to the computer through the parallel port.
There will not be a USB version of this controller.
No. There will probably not be a serial port version of this controller.
That depends. LEDs drop a certain amount of voltage across them. The total
amount of voltage drop must not exceed 4.4 volts. The ultrabright white LEDs
I have been using for testing drop about 3.2 volts, so I could not put more
than one of them in series. Some red LEDs drop only 1.3 volts, so you could
put three of those in series.
No resistor is needed. Yes, I'm sure.
It will not hurt the controller or your LEDs to put resistors in series with
each LED. Remember, though, the total voltage drop across your LED and the resistor,
if any, must be less than 4.4 volts. So, if your LEDs drop 3.2 volts, then
the voltage drop across the resistor must be less than 1.2 volts. At a current
of 24 milliamps, this translates into a maximum value of 50 ohms for the
LED resistor. (V = I*R) If the resistor is greater than the maximum allowed,
then the LED will remain at the level of brightness indicated by the maximum
level of current indicated by the resistor. Example: Your LED drops 3.2 volts,
and your resistor is 80 ohms. Maximum voltage drop across the resistor is
therefore 4.4-3.2=1.2 volts. Maximum current is therefore 1.2/80=15 milliamps.
The controller will only put 15 milliamps through the LED, it will go no
higher.
I don't see why not. However, it's not recommended, because one LED might "hog"
the current, unless carefully chosen resistors are placed in series with each
LED. Also, current will be split between each LED, thus making all the
parallel LEDs dimmer.
The controller is a current source. So it could drive current-driven solenoids
or relays. Without additional circuitry, the device can drive a current-driven
device with up to 24 milliamps of current, so long as the device drops 4.4
volts or less across it.
It can be done with external circuitry. All you have to do is hook the 12 volt
supply from the PC through the LEDs you want to drive, then into the
collector of a transistor. The base of the transistor connects to the plus
side of the controller, and the emitter of the transistor connects to the
minus end of the controller. This change will give you about a 7.5 volt drop
to work with.
The controller costs $69.95 plus shipping. Shipping is $5.00 to the co
You probably can.
There will be two phases of how the ordering will work. In order to purchase
the parts necessary to build the initial run of 50 boards, I need to have
enough money. I don't have the money to just go out and buy all the parts.
Therefore, the first phase of the ordering will be pre-orders.
Here's how the preorders will work. You send me a money order or Paypal
for the cost of the board plus shipping. Once I have enough money to order
the parts, I do that. Boards will be shipped in the order that the preorders
are received.
Important note: My Paypal account is a free account, and therefore
cannot accept all forms of funds transfer. For this board, Paypal would
charge about 2.50 for the transaction. Margins are thin enough on this
board, I am unwilling to upgrade my account for a little extra convenience.
Phase two of ordering will be a lot more normal. You send me a money order
or PayPal, I'll send you a controller.
For the preorders: money order only (continental U.S. only)
For regular orders: Paypal or money order. Orders outside the continental U.S. must
be paid for via PayPal.
The reason I'm not taking PayPal for the preorders is that if not enough
preorders are made within a certain time span, I'll cancel this venture
and mail you back all your money orders. I'll be out stamps for everyone's
money orders, I don't want to be out Paypal charges as well.
I don't want to take overseas money orders, so the Euros, Aussies and others
will have to wait to order their boards until preordering is done. Once I
have built the boards, I'll open up sales to all over the world. I'll do
shipping costs on a country-by-country basis. I won't know in advance how much
it will cost to ship to each particular country, but I promise to not overcharge
on shipping.
I was hoping to not have to do another preorder after the first 50 are sold,
but unfortunately the margins on this product are so low that I may not be able
to build a second run of 50 boards from the money received for the first run.
The package includes an assembled, manufactured printed circuit board (PCB),
a 6' cable with a Molex connector to attach to your computer's power supply,
a 6' parallel port cable, and a CD-R with software on it. The package does
not include LEDs or wiring for the LEDs.
I will test each board to make sure it works before I ship it. The boards are
very rugged, I don't think there is a problem. I'll provide a one-year warranty
against defective boards. This will not cover obvious neglect.
I will assist in helping you configure your software to match your installation.
I will also be available to answer any questions you might have on creating
animations or other effects that the board is capable of.
It measures 6.25 by 3.25 inches.
The board is powered from a connection to your computer's +5v power supply.
Each connection on the board can draw up to 24 milliamps. So, if all 40 LEDs
are lit at full brightness, that's 24*40= 960 milliamps. The components on the
board use a bit of power as well.
Computer power supplies are rated at far higher currents than this, typically tens of amps
on the +5 volt line. So there should be no problem supplying power to the
controller from a PC.
The software currently will run on Windows (I believe all variants). I will
support DOS and Linux if there is demand.
There is an upper limit to 24 milliamps per LED. The current that flows
through the LEDs is in 16 even increments. Some LEDs reach their full
brightness at 20 mA, so some of the increments would not have any effect.
Therefore, I implemented adjustable peak current.
I have put two potentiometers on the board which control the peak current.
One pot controls ports 1 through 20 and the other controls ports 21 to 40.
The peak current is adjustable from 24 mA down to about 10.5 mA. The
increments between levels of current will still be even. The potentiometers
do not have to be set the same. For example, suppose you have six RGB LEDs
on ports 1 through 18. You might set those for maximum brightness. Then,
you might have some ultrabright LEDs on ports 21 through 40. The second
potentiometer might be set so that the maximum current is 20 mA instead of
24.