WS2811 and WS2812 One-Wire Communication Assembly Help

[richard]

I don't have a 12mhz crystal so I am having problems configuring 4550 for 48mhz internal osc. My test board has a 10mhz resonator. The usb pre-scale stuff is throwing me off. If you could help me with the configurations for internal osc 48mhz or 40mhz using the pll and the 10mhz resonator.

the pll input needs to be 4MHz if you are going to use it . a 10MHz resonator
cant be divided down to 4MHz using plldiv to keep pll input within specs .

the xtal/res needs to be a multiple of 4 for correct use, my board has a 20MHz xtal

out of spec operation may be possible but may lack stability required for this use

Also as posted the code makes one pass and stops

yep that's all that code did , you should see a white "R" , a loop serves no
purpose here, the other examples are more elaborate




if you want text scroll

aloop: 

 for  p_offset=0 to 1536 step 24
     p_pc=nows    ;set number of leds to load 
     @ Flash2Ram  _pixels,_rw1' Get a String from flash memory
     p_pc=nows     ;set number of leds to show
     call showpix
     pause 200
  next   
     
 goto aloop     
     stop
end
rw1:
  @ DW  0,0,0, 0,0,0,    0,0,0,    0,0,0,    0,0,0,    0,0,0, 0,0,0, 0,0,0
  @ DW  0,0,0, 0,0,0,    0,0,0,    0,0,0,    0,0,0,    0,0,0, 0,0,0, 0,0,0
  @ DW  0,0,0, 0,0,0,    0,0,0,    0,0,0,    0,0,0,    0,0,0, 0,0,0, 0,0,0
  @ DW  0,0,0, 0,0,0,    0,0,0,    0,0,0,    0,0,0,    0,0,0, 0,0,0, 0,0,0
  @ DW  0,0,0, 0,0,0,    0,0,0,    0,0,0,    0,0,0,    0,0,0, 0,0,0, 0,0,0
  @ DW  0,0,0, 0,0,0,    0,0,0,    0,0,0,    0,0,0,    0,0,0, 0,0,0, 0,0,0
  @ DW  0,0,0, 0,0,0,    0,0,0,    0,0,0,    0,0,0,    0,0,0, 0,0,0, 0,0,0
  @ DW  0,0,0, 0,0,0,    0,0,0,    0,0,0,    0,0,0,    0,0,0, 0,0,0, 0,0,0
  ;192
  @ DW  0,0,0, 50,50,50, 50,50,50, 50,50,50, 0,0,0,    0,0,0, 0,0,0, 0,0,0 ;23
  @ DW  0,0,0, 50,50,50, 0,0,0,    0,0,0,    50,50,50, 0,0,0, 0,0,0, 0,0,0 ;47
  @ DW  0,0,0, 50,50,50, 0,0,0,    0,0,0,    50,50,50, 0,0,0, 0,0,0, 0,0,0 ;71
  @ DW  0,0,0, 50,50,50, 50,50,    50,50,50, 50,0,0,0, 0,0,0, 0,0,0, 0,0,0 ;95
  @ DW  0,0,0, 50,50,50, 0,0,0,    0,0,0,    50,50,50, 0,0,0, 0,0,0, 0,0,0 ;119
  @ DW  0,0,0, 50,50,50, 0,0,0,    0,0,0,    50,50,50, 0,0,0, 0,0,0, 0,0,0 ;143
  @ DW  0,0,0, 50,50,50, 0,0,0,    0,0,0,    50,50,50, 0,0,0, 0,0,0, 0,0,0 ;167
  @ DW  0,0,0, 0,0,0,    0,0,0,    0,0,0,    0,0,0,    0,0,0, 0,0,0, 0,0,0 ;191
  ;384
  @ DW  0,0,0, 0,0,0,    50,50,50, 50,50,50, 50,50,50, 0,0,0, 0,0,0, 0,0,0
  @ DW  0,0,0, 0,0,0,    0,0,0,    50,50,50, 0,0,0,    0,0,0, 0,0,0, 0,0,0
  @ DW  0,0,0, 0,0,0,    0,0,0,    50,50,50, 0,0,0,    0,0,0, 0,0,0, 0,0,0
  @ DW  0,0,0, 0,0,0,    0,0,0,    50,50,50, 0,0,0,    0,0,0, 0,0,0, 0,0,0
  @ DW  0,0,0, 0,0,0,    0,0,0,    50,50,50, 0,0,0,    0,0,0, 0,0,0, 0,0,0
  @ DW  0,0,0, 0,0,0,    0,0,0,    50,50,50, 0,0,0,    0,0,0, 0,0,0, 0,0,0
  @ DW  0,0,0, 0,0,0,    50,50,50, 50,50,50, 50,50,50, 0,0,0, 0,0,0, 0,0,0
  @ DW  0,0,0, 0,0,0,    0,0,0,    0,0,0,    0,0,0,    0,0,0, 0,0,0, 0,0,0 
  ;576                                                  
  @ DW  0,0,0, 0,0,0,    50,50,50, 50,50,50, 50,50,50, 0,0,0, 0,0,0, 0,0,0 
  @ DW  0,0,0, 50,50,50, 0,0,0,    0,0,0,    0,0,0,    0,0,0, 0,0,0, 0,0,0 
  @ DW  0,0,0, 50,50,50, 0,0,0,    0,0,0,    0,0,0,    0,0,0, 0,0,0, 0,0,0 
  @ DW  0,0,0, 50,50,50, 0,0,0,    0,0,0,    0,0,0,    0,0,0, 0,0,0, 0,0,0 
  @ DW  0,0,0, 50,50,50, 0,0,0,    0,0,0,    0,0,0,    0,0,0, 0,0,0, 0,0,0 
  @ DW  0,0,0, 50,50,50, 0,0,0,    0,0,0,    0,0,0,    0,0,0, 0,0,0, 0,0,0 
  @ DW  0,0,0, 0,0,0,    50,50,50, 50,50,50, 50,50,50, 0,0,0, 0,0,0, 0,0,0 
  @ DW  0,0,0, 0,0,0,    0,0,0,    0,0,0,    0,0,0,    0,0,0, 0,0,0, 0,0,0
  ;768
  @ DW  0,0,0 ,50,50,50, 0,0,0,    0,0,0,    50,50,50, 0,0,0, 0,0,0, 0,0,0
  @ DW  0,0,0, 50,50,50, 0,0,0,    0,0,0,    50,50,50, 0,0,0, 0,0,0, 0,0,0
  @ DW  0,0,0, 50,50,50, 0,0,0,    0,0,0,    50,50,50, 0,0,0, 0,0,0, 0,0,0
  @ DW  0,0,0, 50,50,50, 50,50,50, 50,50,50, 50,50,50, 0,0,0, 0,0,0, 0,0,0
  @ DW  0,0,0, 50,50,50, 0,0,0,    0,0,0,    50,50,50, 0,0,0, 0,0,0, 0,0,0
  @ DW  0,0,0, 50,50,50, 0,0,0,    0,0,0,    50,50,50, 0,0,0, 0,0,0, 0,0,0
  @ DW  0,0,0, 50,50,50, 0,0,0,    0,0,0,    50,50,50, 0,0,0, 0,0,0, 0,0,0 
  @ DW  0,0,0, 0,0,0,    0,0,0,    0,0,0,    0,0,0,    0,0,0, 0,0,0, 0,0,0
  ;960
  @ DW  0,0,0, 0,0,0,    50,50,50, 50,50,50, 0,0,0,    0,0,0, 0,0,0, 0,0,0
  @ DW  0,0,0, 50,50,50, 0,0,0,    0,0,0,    50,50,50, 0,0,0, 0,0,0, 0,0,0
  @ DW  0,0,0, 50,50,50, 0,0,0,    0,0,0,    50,50,50, 0,0,0, 0,0,0, 0,0,0
  @ DW  0,0,0, 50,50,50, 50,50,50, 50,50,50, 50,50,50, 0,0,0, 0,0,0, 0,0,0
  @ DW  0,0,0, 50,50,50, 0,0,0,    0,0,0,    50,50,50, 0,0,0, 0,0,0, 0,0,0
  @ DW  0,0,0, 50,50,50, 0,0,0,    0,0,0,    50,50,50, 0,0,0, 0,0,0, 0,0,0
  @ DW  0,0,0, 50,50,50, 0,0,0,    0,0,0,    50,50,50, 0,0,0, 0,0,0, 0,0,0 
  @ DW  0,0,0, 0,0,0,    0,0,0,    0,0,0,    0,0,0,    0,0,0, 0,0,0, 0,0,0
  ;1152
  @ DW  0,0,0, 50,50,50, 50,50,50, 50,50,50, 0,0,0,    0,0,0, 0,0,0, 0,0,0
  @ DW  0,0,0, 50,50,50, 0,0,0,    0,0,0,    50,50,50, 0,0,0, 0,0,0, 0,0,0
  @ DW  0,0,0, 50,50,50, 0,0,0,    0,0,0,    50,50,50, 0,0,0, 0,0,0, 0,0,0
  @ DW  0,0,0, 50,50,50, 50,50,50, 50,50,50, 0,0,0,    0,0,0, 0,0,0, 0,0,0
  @ DW  0,0,0, 50,50,50, 0,0,0,    0,0,0,    50,50,50, 0,0,0, 0,0,0, 0,0,0
  @ DW  0,0,0, 50,50,50, 0,0,0,    0,0,0,    50,50,50, 0,0,0, 0,0,0, 0,0,0
  @ DW  0,0,0, 50,50,50, 0,0,0,    0,0,0,    50,50,50, 0,0,0, 0,0,0, 0,0,0 
  @ DW  0,0,0, 0,0,0,    0,0,0,    0,0,0,    0,0,0,    0,0,0, 0,0,0, 0,0,0
  ;1344
  @ DW  0,0,0 ,50,50,50, 50,50,50, 50,50,50, 0,0,0,    0,0,0, 0,0,0, 0,0,0
  @ DW  0,0,0, 50,50,50, 0,0,0,    0,0,0,    50,50,50, 0,0,0, 0,0,0, 0,0,0
  @ DW  0,0,0, 50,50,50, 0,0,0,    0,0,0,    50,50,50, 0,0,0, 0,0,0, 0,0,0
  @ DW  0,0,0, 50,50,50, 0,0,0,    0,0,0,    50,50,50, 0,0,0, 0,0,0, 0,0,0
  @ DW  0,0,0, 50,50,50, 0,0,0,    0,0,0,    50,50,50, 0,0,0, 0,0,0, 0,0,0
  @ DW  0,0,0, 50,50,50, 0,0,0,    0,0,0,    50,50,50, 0,0,0, 0,0,0, 0,0,0
  @ DW  0,0,0 ,50,50,50, 50,50,50, 50,50,50, 0,0,0,    0,0,0, 0,0,0, 0,0,0
  @ DW  0,0,0, 0,0,0,    0,0,0,    0,0,0,    0,0,0,    0,0,0, 0,0,0, 0,0,0
  ;1536
  @ DW  0,0,0, 0,0,0,    0,0,0,    0,0,0,    0,0,0,    0,0,0, 0,0,0, 0,0,0
  @ DW  0,0,0, 0,0,0,    0,0,0,    0,0,0,    0,0,0,    0,0,0, 0,0,0, 0,0,0
  @ DW  0,0,0, 0,0,0,    0,0,0,    0,0,0,    0,0,0,    0,0,0, 0,0,0, 0,0,0
  @ DW  0,0,0, 0,0,0,    0,0,0,    0,0,0,    0,0,0,    0,0,0, 0,0,0, 0,0,0
  @ DW  0,0,0, 0,0,0,    0,0,0,    0,0,0,    0,0,0,    0,0,0, 0,0,0, 0,0,0
  @ DW  0,0,0, 0,0,0,    0,0,0,    0,0,0,    0,0,0,    0,0,0, 0,0,0, 0,0,0
  @ DW  0,0,0, 0,0,0,    0,0,0,    0,0,0,    0,0,0,    0,0,0, 0,0,0, 0,0,0
  @ DW  0,0,0, 0,0,0,    0,0,0,    0,0,0,    0,0,0,    0,0,0, 0,0,0, 0,0,0
  @ DW  0,0,0, 0,0,0,    0,0,0,    0,0,0,    0,0,0,    0,0,0, 0,0,0, 0,0,0

[mark_s]

Richard

I changed the crystal to 20mhz and added the scroll code above. It's now working, so thanks for your efforts.

I'll study the other code and see what I can do.

Mark

[Ioannis]

Similar to WS2811/2812 is the APA102C led chip, produced as a strip too.

The Datasheet is unclear of the timing specs.

I tried many hours to make it work but in vein. No led so far is under my control. Any ideas, welcome.

An example code is this:

arraywrite leds,[0,0,0,0,$f0,128,128,128,255,255,255,255]

shiftout led_data,led_clock,1,[leds[0],leds[1],leds[2],leds[3],leds[4],leds[5],leds[6],leds[7],leds[8],leds[9],leds[10],leds[11]]

Lcdout  $fe,$1,"Stoped"
stop

Any help?
Ioannis

[richard]

this may help

[Ioannis]

Hi Richard.

Thanks for the link. The real help was ... the color of the cables. On my strip the ground is Blue and +5V is Black. Really! They made +5V Black!

Of course I used Black as ground and that was the problem.

Be careful if color is not red then,

Black is +5, NOT ground.
Blue is Ground.

Chinese people might have a different color preferences...

I had it working now. Almost got crazy, since logic analyzer was showing all was OK!

This type of LED's is more easy to control since they do not need strict timings. Just spit out at whatever pace you like or can and LED's follow. Very easy for any MCU.

People have reported driving SPI up to 60MHz on these strips.

Ioannis

[Ioannis]

The following is a simple test program to demonstrate how to use of APA-102 leds.

It lights the Blue led and shifts it ten places in 100ms interval.

To successfully manage this, tens of hours were spent... Datasheet sucks.

But in general is much easier to control as the timings are those of an SPI interface and can be really fast driven if you have the resources.

arraywrite red_a,[0,0,0,0,0,0,0,0,0,0,0]
arraywrite green_a,[0,0,0,0,0,0,0,0,0,0,0]
arraywrite blue_a,[255,0,0,0,0,0,0,0,0,0,0]

gosub display_led

stop

display_led:
    for k=0 to led_num
        for i=0 to led_num
            shiftout led_data,led_clock,1,[lum,blue_a[i],green_a[i],red_a[i]]
        next i
    gosub shift_sub
    next k
    pause 1000 'delay from one color to another
return

shift_sub:
    shiftout led_data,led_clock,1,[%11100011,0,0,0,0,0] 'END of Frame
    pause 100'led move step delay
    temp=red_a[k]:RED_A[k]=RED_A[k+1]:RED_A[k+1]=temp
    temp=green_a[k]:green_a[k]=green_a[k+1]:green_a[k+1]=temp
    temp=blue_a[k]:blue_a[k]=blue_a[k+1]:blue_a[k+1]=temp
return

Ioannis

[richard]

But in general is much easier to control as the timings are those of an SPI interface and can be really fast driven if you have the resources.

I had 3 in the parts bin , so I had a go using mssp module . @64mhz with the fastest spi clk its no problem at all .
a complete 3 led frame is less than 80uS . heaps easier than ws2812