Cyrix Foundry Agreements

Cyrix extended its wafer supply agreement with SGS-Thomson in 1994 (Originally
formed in 1990). Under the new arrangement,
SGS-Thomson increased the number of wafers it produces for Cyrix and
is allowed to make a certain
percentage of those same wafers for itself. In addition, Cyrix granted
SGS-Thomson the right to use
certain Cyrix-designed chips as part of SGS-Thomson’s ASIC libraries.
SGS-Thomson is allowed to
produce and sell such ASIC products under its own name in unlimited
quantities, with Cyrix receiving
royalties from the sale of the devices. Also, Cyrix has the right to
sell the SGS Thomson-designed ASICs
under its own name.

IBM and Cyrix announced a five-year agreement in (Sept 1993) calling
for IBM to manufacture Cyrix’s 486, 5×86,
and 6×86 MPUs. The two companies equally share the output of the Cyrix-designed
chips. (Terminated in 1998 after The National Buy Out)

Differentiating between Cyrix and IBM Blue Lightning

It is difficult to distinguish IBM Blue Lightning CPU from Cyrix CPU.
The behavior of both CPU is very similar to each other. The deference
is that IBM Blue Lightning CPU supports MSR but Cyrix 486, 5×86 and
6×86 do not support it. This means that wrmsr instruction cause invalid
opcode fault on Cyrix 486, 5×86 and 6×86, but does not on IBM Blue Lightning
CPU. To detect invalid opcode by wrmsr, the following handler is prepared:

If we have Cyrix 486, 5×86 or 6×86, the variable trap_by_wrmsr will
be change by this handler. Once Cyrix CPU is detected by this method,
we will check device ID register to distinguish it.

Time Line

CYRIX
CORPORATION, Plaintiff, v. INTEL CORPORATION, Defendant, v. TEXAS INSTRUMENTS,
INC., Intervenor.

NO. 4:92cv52
UNITED STATES DISTRICT COURT FOR THE EASTERN DISTRICT OF TEXAS, SHERMAN
DIVISION
846 F. Supp. 522; 1994 U.S. Dist. LEXIS 3477; 32 U.S.P.Q.2D (BNA) 1890

January 21, 1994, Decided

CONCLUSION

Cyrix is entitled to judgment in its favor on its affirmative defenses
of patent exhaustion and implied license based on the use or resale
of its claim 1 microprocessors purchased from TI and ST.

Signed this day of January, 1994.

UNITED STATES DISTRICT JUDGE

See Also
Cyrix Corp. v. SGS-Thomson Microelectronics, Inc., 77 F3d 1381 (Fed.
Cir. 1996).

Cyrix Corporation and SGS-Thomson Microelectronics, Inc. v. Intel Corporation,
803 F. Supp. 1200, 1205-06 (E.D. Tex. 1992),

Cyrix CX486 S Series (TI Produced)	Cyrix DRx2 Clock Doubled 386 Design	Cyrix Cx486DX DX2 and DX2 ST Produced	Ca486DX2 v-XX IBM Made	Cyrix Cx486DX4 Cyrix 5×86 (and ST) IBM Produced
	(these can be on the tops as well)	DX2-50DX-33 DX 40 DX-2 80GP		DX4-100 5×86 Cyrix AND ST
FFMYWWL			GPFMYWWL	GPFMYWWL
			G IBM P Process 1 3.6V 3 3.45V 4 3.6V F Fab B Burlington, Vermont C Corbeil France F Fish Kill, NY J ? K Bromont, Quebec M Mask Revision J N Q S B Y Year 4 1994 5 1995 WW Week L Die Lot Code	G IBM P Process 3 486 5 586 0.65u F Fab F K L M Mask Revision U 7 8 9 B Y Year 5 1995 6 1996 WW Week L Die Lot Code

586-120 Samples October 30, production Nov 1995

1990 SGS-Thomson agreement
1995 .35u AT 586/686 5 Layer Phoenix