Faster COSMAC ELF

FASTER COSMAC ELF

What do you get with a COSMAC ELF in FPGA? You get an Elf that's 100 times faster than the original.

Project by Eric Smith. "The original COSMAC Elf ran at 1 to 2 MHz.  Every machine cycle required eight oscillator cycles, and each instruction required two or three machine cycles, so each instruction took 8 to 12 microseconds at 2 MHz, or 16 to 24 microseconds at 1 MHz.

The FPGA-Elf runs at 25 MHz when using a Spartan-3E FPGA in the slow speed grade, but it also needs only one oscillator cycle per machine cycle.  That means that each instruction takes 80 to 120 nanoseconds.  That’s 100 times the speed of a 2 MHz COSMAC Elf!"

http://whats.all.this.brouhaha.com/2010/07/30/fpga-elf-is-100-times-faster-than-original-cosmac-elf/

http://whats.all.this.brouhaha.com/2010/07/30/video-of-demo-of-fpga-elf/ 

http://www.youtube.com/watch?v=4IhDMDVBYio

http://www.youtube.com/watch?v=Hmko_V0tQrc

BASIC Stamp Hacking

BS1 ceramic resonator pins

HACK A BASIC STAMP & HOTROD THE SPEED 2X AND 4X FASTER!

Build the Turbonizer Basic Stamp

BASIC STAMP HACKING
Hack a BASIC Stamp, like the BS1 for example, to increase its speed, either doubling the clock or making it four times faster! This is a substantial improvement over the standard Stamp's clock.

POWER TURBO This powerful TURBO mode is created by replacing the 4MHz resonator with 8 OR 16MHZ high speed ceramic resonators or crystals, to double or quadruple the Stamp's speed. It's suggested to move the resonators for various speed functions with jumpers.

HACKING The faster resonator is connected across OSC1 and OSC2 as seen in the schematic. Keep the leads as short as possible.

PROGRAMMING The caveat is programming requires the original 4MHz clock, so the use of jumpers will be needed for the extra crystal(s).

OPERATIONS Keep in mind, timing, such as Baud rates, PAUSE and other time dependent programming statements and operations will be modified. For example, a serial output command may specify 2400 Baud, however, running with 16MHz resonator will create an actual Baud rate of 9,600.

RESONATORS Only one resonator is used at a time. Jumpers could switch three resonators for three speeds, one standard at 4MHz, and two turbo modes at 8MHz and 16MHz.

BLAZING SPEEDS ATTEMPTED
The lab is attempting much higher speed with a variety of ceramics, many of which were offered by Parallax. It's unknown which frequencies will work and not work. A limit is currently being investigated.

PARALLAX RESONATORS AND CRYTALS 
20 MHz Industrial Resonator
20 MHz resonator (DIP)
32.768 kHz Series Crystal
32MHz Resonator 
4 MHz Industrial Resonator (DIP)
5 MHz Crystal
50 MHz Industrial Resonator (DIP)
6.25 MHz Crystal
8 MHz Resonator