REQUEST: REPORT
ID:N8CUDX
P-NAME: SPANKY
Fab-ID: 56998/67
P-P:
REPORT:

Overview of Chip Functionality:

	We received 5 fully fabricated and packaged chips from MOSIS.  Each
package showed proper power-to-ground resistance upon receipt.  Confusion over
the proper orientation of the padframe brought about the failure of four of
the five chips before proper testing.  By connecting the power rails
backwards, we shorted power to ground in some chips and disconnected the Vdd
rail completely in others.
	Using the one remaining chip, we verified near complete
functionality.  As a CPU, our chip design included several 8bit buses.  One of
the main register buses proved unable to properly carry a high signal.
Testing suggests that the error is due to weak driving signals on two of the
eight bits, or gates which did not properly switch to high-impedance.  We were
unable, with only a single chip, to ascertain whether the error was due to a
fabrication error or a design flaw.

Speed testing:

	We tested the speed performance of our near-functional chip using the
omnilab test equipment.  With the exception of the faulty two bits on the
register bus mentioned above, our chip maintained full functionality up to a
speed of 6.8MHz.  At 17MHz, some signals were slow to switch, although the
chip was still functional.  At 34MHz, the chip no longer produced reasonable
output. 

Chip design overview:

	SPANKy is an eight-bit RISC CPU, designed as part of the VLSI course
here at Rice University.  It has a full range of basic arithmetic and logical
operations, can address a total of 512 bytes of memory, and allows for limited
user interaction.

	We designed the architecture with functionality and simplicity as the
two main goals.  In keeping with the RISC tradition, SPANKy is a load-store
architecture, has uniform-length instructions, and even comes with extremely
short mnemonics for the SPANKy assembly language.

Contact information:

A full web-based report on our chip is available at

<http://www.owlnet.rice.edu/~geels/spanky/spanky.html>

Team members:

Victoria Smith (vics@rice.edu) 
Mara Prandi-Abrams (mabrams@rice.edu)
Dennis Geels (geels@rice.edu) 


REQUEST: END