P2 firmware bug

AAH

I love blinky lights :)
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A bit of background first. I used my P2 all Xmas 2013 with 1 output driving my 170 2811 pixels. Yesterday a legend in Xmas lighting did some damage to her P2 while testing so I am now very gun shy when connecting up. As a result I hooked my oscilloscope to my P2 in preparation to testing my new 2801DC boards. I was going to leave output 1 as 2811 and run 2801 on output 2. I checked that I was getting an output in preparation to hook up my board. I noticed that the 2811 output had both data and clock being pumped out (2811 doesn't need this) and the 2801 output had data only (it needs data and clock). I swapped backwards and forwards between 2801 and 2811 several times on both outputs and each time I got the result. It was getting late last night so I thought I may have been a bit punchy so I gave up. Today I have tested and tested further and even reflashed the P2. It had and has the latest version which is 2.7. I didn't erase the P2 first but after getting the same results I will whilst waiting for a reply. Below are some terrible photos which show the output waveforms of the data and clock outputs followed by the string config. The 1st is what I got with 2811 and then with 2801.
The cro photo was taken seconds before the lappy picture in each case and I had done the save and reboot process to make the changes stick.
 

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No bug. WS281x does indeed create a clock signal that is unused.

2801 does have both or it won't work. On a P2 it is a physical connection through a 541 driver and 300 ohm current limiter. Perhaps your output is blown on one string.

I personally test all ports on all pixel devices before shipping with a string of 8 2801 pixels that hangs by my computer. If it works, both clock and data have to be working.

Ed
 
I've checked on both sides of the 300R resistor and other than a bit of rounding the signal is the same. With more testing I worked out to replicate the bug. When all zeroes are getting sent to the P2 it turns off the clock regardless of packets being sent to it. If I wasn't being so cautious with connecting up to the board I wouldn't have even noticed that this occurs.
 
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