Here is a faster Blue August:
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I think this might just squeak by at 16MHz. This is pretty close to having my cake and eating it, but I did have to give up the ability to move the I/O window into high RAM. When you're trying to cut close to the bone, one gate delay can be the difference between a 60ns (16MHz) and a 70ns (14MHz) cycle time!
I can actually build this version on the existing Blue August board, with some extensive rewrapping. I would need to combine the LO_RAM and HI_RAM signals into a single RAM_CS, but that wouldn't be a problem.
But, while I've been working on this, I've also been building something else... call it SPC for Standard Pag Computer.
Whenever I get into trouble with one of these projects, it seems like it always happens because I've deviated from some general some design principle in order to build some specific thing. Or, maybe a better way to put it is, focusing on building a specific design (from a schematic or whatever) distracts me from the abstract model of good practice. So, I built a kind of philosophical prototype board. With no specific 6502 system in mind, I took one of the same prototype boards that Blue August and Peanutbutter-1 are made of, and I started by tying the VCC and GND buses together in a grid, and putting on a generic pin-header edge connector.
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Then I started adding IC sockets; not with any particular design in mind, but just trying to fill in the VCC / GND grid in a consistent way that would maximize the use of space:
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There are five general 14-pin sockets, plus one 14-pin socket wired up to hold a full- or half-can oscillator. There are five 16-pin sockets, and two 20-pin sockets. I included two 28-pin narrow sockets and one 28-pin wide socket, and a socket for a 6502, of course! I desoldered the DS1813 from the first (failed!) Blue August build - no sense in letting it go to waste - and moved it over. I also put on a resistor bank (47k) and some single resistors (3.3k) that can be used for pull-ups/downs. I still need to add some bulk power supply decoupling and some wire-wrap pin headers.
I quite like how it's looking. It may sound silly, but one reason I like it is that the 28-pin socket will let me use my Aries ZIF socket again (I only have a 28-pin one, not a 32-pin one). It just makes a hobbyist's life better!