DMX to WS2801 Pixel Bridge

[fathead45]

ok so i have my first one built. now a question now that i was thinking. jw if these are default to 1 and 2 univ? so i cant change that? also is there no way to set a start address of each just in case i only have a few pixels on each one?

also is the firmware still set for only 1 univ split between the 4 univ?? sorry for all the questions lol.

[fathead45]

still looking for answers to questions above^^^^^^

also one more, can i run more than 42 off 1 port, im in need of 50 per port for 3 ports.

[Mac Hosehead]

still looking for answers to questions above^^^^^^

also one more, can i run more than 42 off 1 port, im in need of 50 per port for 3 ports.

If you examine the assembly source code, it looks like this can be accomplished. I would try changing BANK_CHANNELS to 150 and then deleting the code for OUTPUT CHANNEL BANK 4.

-MH

[fathead45]

ok thanks. sorry im not a code monkey lol.

[Mac Hosehead]

I tried out this method for dimming 6803 pixels on RPM's design:
http://doityourselfchristmas.com/for...for-old-pixels
If I had all 4 outputs enabled, it flickered pretty badly. So I disabled 3 outputs and left one enabled and I could not notice any flicker. It is nice to see the brightness change with each DMX step.

BTW, I'm not a code monkey, more like a hack monkey.

-MH

[Mac Hosehead]

I tried out this method for dimming 6803 pixels on RPM's design:
http://doityourselfchristmas.com/for...for-old-pixels
If I had all 4 outputs enabled, it flickered pretty badly. So I disabled 3 outputs and left one enabled and I could not notice any flicker. It is nice to see the brightness change with each DMX step.

BTW, I'm not a code monkey, more like a hack monkey.

-MH

I went to 127 steps instead of 255 and I was able to get all four outputs working acceptably. I can barely notice a little flicker on the first two steps but I have to look closely. I am attaching the modified source code if anyone wants to try it out. It's a keeper for me. Of course, this is only for 6803 pixels. Thanks go to RPM for the hard work.

NOTE: I am using a ATMEGA328P processor. If I remove the comment on an include statement AVR Studio complains. Your assembler might need the proper include statement for the processor you are using.

-MH

[Matt_Edwards]

Great work.
What happens when you increase the spi clk. Does the flickering get worst or better?

[fathead45]

what programmer do i need to reprogram these?

[Mac Hosehead]

@Matt_Edwards
No changes were made to the output routines, only the way data is supplied to the routines. Originally data was supplied via a look-up table with 32 levels. The change looks at the lower 3 bits of DMX and adjusts the data to achieve a virtual 127 levels. I'm sure more optimization is possible but at present it looks good enough for anything I'm doing. Other changes can be easily made such as strings with different lengths.

@fathead45
There seems to be a myriad of AVR programmers. The one I'm using is based on this:
http://www.fischl.de/usbasp/
I'm am using a pre-made one bought from here:
http://www.protostack.com/blog/
This is a cool site and includes tutorials for the DIYer. I buy other supplies from here as well. One issue is the ISP connector. I use a 10 pin header which also supplies power from USB to the circuit being programmed. You might need an adapter cable to the ISP connector you are using. The signals are the same just arranged differently.

-MH

[matimix]

I like the design you made for the pixel bridge, but what do I have to do to control lpd6803 chips (single strip bridge), in the reloaded quad bridge you can choose between ws or lpd, but I can't find it in the single bridge firmware.

(sorry for obvious question, but I'm pretty new at this, and sorry for bumping the topic)