Just wanted to let you know I finished putting together my Wise Clock 4 and it looks and works great! Only took me about 6 months to get started it J . Thanks for putting together such a nice kit. I didn�t install an xbee on it yet but hope to experiment with that sometime this year. I really like all the different modes � and have to read up on what they all do. Is there a good link you can point me to that describes them? Hope you are still working on new clock ideas. Think I saw your name as a supporter of the word clock out on kickstarter? Bill On the 3216 LED display from Sure Electronics: I did look at the clocking relationships on the scope. The clock to data hold timing on the HC164 was marginal, 2ns, versus -2ns typical and 4ns minimum. Meaning it will probably work, but it's not certain. CLK, DATA and WR are buffered through 2 sections of an HC04, with a delay of 11ns, but CS_OUT is not, so with every successive board in a chain this timing degrades.