I decided to start the new year with some PCB Layout. Can you tell what it is? I am not sure if it is a good or a bad thing if you can recognize the footprint, but you are definitely in good company I recognize them pretty much instantly on other boards. :)

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Finished layout keeping the board pinout backward compatible to the original single Hyperram Pmod. It is not good though as the traces to the Hyperram chips are not even remotely length matched. Need to redo it...

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Thanks to @tnt encouragement. I have re-routed the board. While I could not keep pinout backward compatibility, the data, RWDS and clock signals are length matched. Not sure how important the length matching will be in practice, but "what is worth doing is worth overdoing!" :D

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Now also added an optional 1v8 regulator to the Hyperram Pmod, to allow the use of S27KS parts. You still have to change the host IO voltage to 1v8 too but at least you don't have to rewire the host Pmod supply voltage. Thanks for prototyping the solution @ln :D

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Placed the pinout silkscreen legend on the board. I think we are ready to place an order for a few Quad Hyperram Pmod PCBs! :D

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And here we go! Placed an order for a few prototype Quad Hyperram Pmod boards with oshpark and for a stencil from OSHStencils ! If everything goes well they should arrive around the same time when I arrive home. :D (I am still mesmerized by the "snek" layer, more cleanup later)

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@esden that's too easy. once you place a hyperram, you see them instantly on any pcb.

@ln hehe, judging by the twitter comments it was harder than I anticipated. :D But yes, you are correct! Need to make a new batch of hyperram pmod for the store so why not work on an improved version at the same time? :D

@esden haha, same :D i just added an ldo for the 1.8V version because I wasn't sure how much of a hassle it would be to get it from the icebreaker ^^

@ln Nice! Let me know how that works out. I guess you will rewire the iCEBreaker IO to 1v8 to use that hyperram Pmod? I am also curious how much speed you will be able to squeeze out of the ice40up5k. Looking forward to your updates on this! Maybe I should add the vreg footprint to my design to make it future proof? :D

@esden I can recommend putting one on it ;) though i have to look for the project files, because i forgot which one i put on it ^^ and yeah, i'll need to rewire the IO for it. good thing we have two at home so we can have one for 3.3V and one for 1.8V.

unfortunately it's on my "projects to finish" pile, so it might take a few weeks until i have an update on it :D but i will post about it!

@eqe @uint8_t you are welcome! There is always something new to learn out there :)

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