for the 8x8x8 led cube what would i change in the ready made code to make the cube work with a usb to parallel cable?

I have the code for the 8x8x8 led cube from this instructable https://www.instructables.com/id/How-to-build-a-8x8x8-led-cube-English-version/ and am trying to make it work with a usb to parallel cable. I'm using vb 6.0

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frollard7 years ago
That instructable already runs over the parallel port to get programs to the cube.  You would just point the programs included on the instructable to the artificial lpt port installed with the usb adapter.


Again, build it exactly the same - then plug it into the usb to parallel cable.  Some may/may not work if it does any manual bit-banging.
deanevans (author)  frollard7 years ago
hi, thanks for the quick response. im not much of a programmer and this is my first project like this. how exactly would i "point" it to the port?
when you install a parallel port it shows up in the computer as a comm port - lpt0, lpt1, lpt2, etc...

find the one that gets installed, and *(I dont know the specific program they include in the instructable) point that program at the right lpt port.  Somewhere they will mention how to configure it.
deanevans (author)  frollard7 years ago
i think I've may of found my problem. the usb parallel converter i have gets installed as a usb device. It comes up in device manager as "usb printing support" and that's in "usb" not "ports". Is there any way make it install as a port instead of a usb device?
That might be a problem if it only allows software control of the port - to use it as a parallel port you need hardware physical layer control of the pins.

Again I don't know that specific adapter - perhaps it can be configured.
deanevans (author)  frollard7 years ago
I have just brought a express card for my laptop and when i plug it in with the cube attached it flashes all the lights on but that's all i can get out of it. I'm now thinking that the code my be the problem. Any help would be appreciated.

I'm not familiar with the code...looking at the instructable...


You'll have to use the pin from D0 to D5 connetting like this:
D0 -> input shift register columns
D1 -> clear shift register columns
D2 -> clock shift register columns
D3 -> input shift register layers
D4 -> clear shift register layers
D5 -> clock shift register layers

CAUTION : If the pins are not connected as described above, the control software will not work

- I would check that first.
deanevans (author)  frollard7 years ago
i have checked all of that and it is all correct. But now I think i have found the problem. the express card I have bought installs itself as a usb device "usb printing services". Is there any way that this can be changed to a lpt port? I've done some research and all i could find was the loopback adapter fix for windows xp and am unsure how to do it in vista. any help would be appreciated.
You might need an older computer that uses a real parallel port... :(
deanevans (author)  frollard7 years ago
I now have borrowed an old computer from a friend and the cube semi works!! :) but not completely. my new problem is that only some of the  lights work. i no that they do work with another power but not plugged into the computer. is it possibly for the resisters are failing somehow? or that the leds are getting to much power and overloading?