Cypress 8x930Ax - Manual

Cypress Semiconductor Corporation

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3901 North First Street

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San Jose

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CA 95134

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408-943-2600

February 25, 2000

Converting from Intel 8x930Ax to Cypress EZ-USB

Introduction

In 1999, Cypress partnered with Intel in an exclusive product
licensing agreement for the USB Intel product family. As a
leader in USB peripheral solutions, Cypress pursued this op-
por tunity for two reasons, to provide another option for the
Intel customer base and to promote the USB technology.

This product licensing agreement consisted of two phases.
The first phase was an exclusive buy/resale agreement be-
tween Cypress and Intel. As previously agreed to by both par-
ties in the product licensing agreement, the buy/resale phase
will expire in October of 2000.

The second phase is an option to manufacture these former
Intel USB devices in Cypress fabs. After several months of
conducting market research, the overall demand for the
former N8x93x family of USB microcontrollers does not offset
the costs associated with transferring and manufacturing of
these devices in Cypress fabs. As a result, Cypress is official-
ly announcing the obsolescence of these former Intel USB
microcontroller devices. Cypress will accept lifetime buys on
all of the listed products per the following schedule:

All par ts are for commercial temperature.

Cypress will accept end-of-life buys on the affected products
through May 12, 2000, for delivery from now until October 12,
2000. In addition to offering a lifetime buy opportunity, Cypress
will provide design conversion assistance for transitioning your
design to a comparable Cypress USB microcontroller.

The Cypress family of USB microcontrollers can offer a num-
ber of benefits relative to the former Intel N8x93x family, in-
cluding improved USB performance, greater flexibility, gener-
ally lower system costs and greater availability with short
lead-times. In addition, many applications may benefit from a
nearly seamless transfer to our equivalent 8051-based USB
microcontroller family. For instance, a MJPEG reference de-
sign by Zoran was converted in four weeks with an increased
performance of 40% and still achieved a 15% reduction in
system cost. This white paper provides pointers on how to
convert the 8x930AX design into an EZ-USB family member,
along with comparisons between the two USB microcontroller
families.

Intel 8x930Ax vs. EZ-USB Family Architectural
Differences

The Intel 8x930Ax device is a first-generation generic USB
microcontroller, merging existing MCS 51/251 controllers with
standard USB SIE technology. To make it easier for peripheral
manufacturers to ease into the complex world of USB,
EZ-USB took the concept of the general-purpose USB micro-
controller further by implementing a Smart USB Engine Core.
This Smart USB Engine Core is so intelligent that it can re-
spond to host controller commands and pass a USB Chapter
9 compliance test without the need for the microcontroller.
EZ-USB handles USB protocol commands more efficiently
than the earlier Intel architecture, as the majority of USB re-
quests are handled without the involvement of the internal
microcontroller.

With this architecture, USB peripheral developers can mini-
mize their knowledge about USB and concentrate on their
application firmware, while still achieving the benefits of a ge-
neric USB microcontroller. The diagrams below illustrate the
efficiency of EZ-USB by comparing how the two USB micro-
controllers handle the “Get Descriptor” host controller com-
mand.

Figure 1 shows how conventional USB controllers, such as
the Intel 8x930Ax, handle a three-stage USB SETUP transfer
called “Get Descriptor”. The serial data flowing over the USB
is shown as three stages: Setup, Data, and Status. The num-
bered arrows indicate transfers between the USB, endpoint
FIFOs, and microprocessor memory. Significant CPU over-
head is required to transfer the data to and from the endpoint
FIFOs (2,3,5) and to divide the descriptor table data into pack-
ets for transmission using multiple USB data packets (4,6).

Figure 2 shows how the EZ-USB handles the same “Get De-
scriptor” command. The EZ-USB core directly transfers setup
packet data into a dedicated eight-byte setup data buffer for
CPU inspection (1). Then the 8051 loads an EZ-USB pointer
with the start address of the requested descriptor data (2).
The EZ-USB Smart Engine Core does the rest. The Smart
Engine Core automatically takes care of error checking and
retries, dividing the table into packets for the various IN trans-
fer and responding to the Status stage.

A good way to measure the efficiency of the Cypress solution
is to compare the firmware sizes between EZ-USB and Intel
for the same function. The following functions were download-
ed from Intel website and compiled.

• USB Chapter 9 Test

• String Descriptors

• USB Suspend and Resume

• Remote Wake-up

• Bulk Endpoint Loopback

Pruned Cypress

Part Number

Corresponding

Former Intel Part

Number

Package

Hub

CY7C69300AD-JC

N80930AD

68 PLCC

No

CY7C69300HF-JC

N80930HF

68 PLCC

Yes

CY7C69310AA-JC

N80931AA

68 PLCC

No

CY7C69310AA-NC

S80931AA

64 MQFP

No

CY7C69310HA-JC

N80931HA

68 PLCC

Yes

CY7C69310HA-NC

S80931HA

64 MQFP

Yes