>The New York Times: Chuck Peddle Dies at 82; His $25 Chip Helped Start the PC Age.
https://www.nytimes.com/2019/12/24/technology/chuck-peddle-dead.html

>6502 microprocessor.

I was a fan of the Z80 microprocessor, which I viewed as 'the 8080 done right'.  https://en.wikipedia.org/wiki/Zilog_Z80     Single +5 supply, single-phase clock, TTL compatible I/O (except for the CLK, which was pulled to +5 with a resistor), and a decoded memory and I/O system.  I also thought the relatively large number of internal registers, much more than 6800 or 6502, was more efficient, minimizing memory accesses.   The Z80 also had a mirrored set of registers, and an enhanced instruction set, including relative-addressing. 

 It also generated a 7-bit refresh address, making use of DRAM easy.  This, however led to a problem when some DRAM manufacturers of 64K DRAMs (I think, including Micron Technology) built DRAM chips needing an 8-bit refresh address.  It meant that those DRAMs simply would not work (reliably) if they depended on Z-80 refreshing.   If Zilog had only added another counter to that chip in the beginning!

Starting in the summer of 1978, I built my homebrew "Bellyache I", the name parodied from the "Illiac IV".  https://en.wikipedia.org/wiki/ILLIAC_IV    I used what would look like S-100 bus hardware, but I was so disgusted by the (lack of) 'architecture' in the S-100 that I merely used a motherboard and prototype boards, and I completely re-defined the bus.  This meant that I only could add functions I myself had designed and constructed.  The Bellyache I eventually had as many as 600 IC's, and this included my prototype "SemiDisk", a S-100 prototype card with 32 memory sockets, each with 8, 2118 (16K, 5-volt only) DRAMs in CERDIP packages, stacked 8 chips high.  This was completed in about October 1980.  (I started work at Intel early July 1980)  It looked like a brick, and weighed just about as half of one!   In implementing that, I had just invented the Disk Emulator, or semiconductor disk.  Technically, there may have been a similar thing for mainframes, but mine was the first for Personal Computers.  

My company, SemiDisk Systems, Inc, eventually built boards for the S-100 bus, Radio Shack Model 2, IBM PC (8-bit bus), IBM AT (16-bit bus), and the Epson QX-10.

         Jim Bell