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コントローラー Cypress AN2131SCのPDF 製品マニュアルをオンラインで閲覧またはダウンロードできます。Cypress AN2131SC 16 ページ。 Ez-usb series 2100 usb controller
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Automatically Handles Low-Level USB Overhead
A USB hardware connection
is simpler than current
interface standards (ISA,
PCI, serial, parallel, and
SCSI). For example, there
are no IRQs or DMAs to set.
USB does not use direct
connections like RS232 or
EPP (Enhanced Parallel
Port). Instead, USB is a
packetized protocol similar
to telecommunication
standards such as X.25 or
frame relay. This makes
software development
complex.
EZ-USB Series 2100
The EZ-USB chip family reduces
the complexity of USB. It has a
predefined default descriptor
that causes it to function as a
generic USB device. Very little
code is required to operate the
EZ-USB chip when configured in
this default state. The default
descriptor can be replaced as the
peripheral manufacturer devel-
ops customized firmware.
Four Major Benefits of
Smart USB Core
1
The firmware code is
smaller and more
efficient than alternate
USB solutions. In the EZ-USB
family, the memory requirement
is reduced by a factor of two to
five times as compared to other
solutions. And, since less memory
is needed for firmware, board
size and system cost are reduced.
Efficient EZ-USB Code
Firmware
EZ-USB Family
File Type
Source
730 lines of C code
Binary
< 1 Kbyte
Test Code Supports:
·
USB Chapter 9
·
String descriptors
·
USB suspend/resume
·
Remote wake-up
·
Bulk endpoint loopback
2
USB firmware develop-
ment is faster since there
is less code to write. This
reduction in firmware allows the
design team to concentrate more
on software development for the
peripheral function.
3
Fewer 8051 MIPs are
dedicated to USB
processing. With the
EZ-USB family, as little as 10% of
8051 processing time is dedicated
to USB. That makes 90% of the
enhanced 8051 core's processing
time available for peripheral
functions. Alternate solutions
dedicate more of their micro-
controller bandwidth to USB
processing.
4
The EZ-USB family
handles most low-level
USB overhead automati-
cally. Therefore, the learning
curve to understand all the
nuances of USB is reduced,
yielding fewer code errors and
faster product development.
Alternate Solutions
5445 lines of assembly code
> 5 Kbytes