l*******k 发帖数: 1974 | 1 各位高人,
要做一个USB与I2C接口的电路。
有什么芯片可以用吗?
谢谢 |
t*********g 发帖数: 124 | 2 phillips has this kind of chip. I don't remember the chip number, but I
think it was called I2C USB conversion bridge. probably under the UART
bridge catalog. you might need micro-controller to go with these conversion
depends on the specific application. The easiest way is to call them and
tell them what you need. |
l*******k 发帖数: 1974 | |
f*****0 发帖数: 489 | 4 or get a PIC12F675 and just program a few pins. |
l*******k 发帖数: 1974 | 5 PIC12F675 只比 PIC12F629多了4个A/D通道。PIC12F629应该也可以完成这个转换功能
吧。
大概看了看PIC12F629/75的datasheet。I2C可以用GP0和GP1实现。
usb的数据传输用哪几个pin如何实现呢。
谢谢
【在 f*****0 的大作中提到】 : or get a PIC12F675 and just program a few pins.
|
l*******k 发帖数: 1974 | 6 相比较PIC12F675,
好象PDIUSBD12专用于USB,比较容易开发?
另外看到一个Atmel的8位单片机,ATTINY 45-20PU。尺寸还要小。
http://www.harbaum.org/till/i2c_tiny_usb/index.shtml
这个星期要订好方案。没做过,不知道各个解决方法的优势劣势。做过的指点一下吧。 |
f*****0 发帖数: 489 | 7 pretty much any pic will do.
pic675/629 is a dip8 device and has 6 GPIO pins. however, gp3 is input only
and others are all bi-directional. so if your chip is to be used in one
direction, it is not a problem.
I would use gp0/gp1 in one direction (i2c or usb), and gp5/gp4 in another
direction (usb or i2c) for easier layout.
if you do this, you are limited to use just the internal oscillator.
another approach, if you want to save one of the clock pins, is to use gp3
for i2c's scl if it is input on |
l*******k 发帖数: 1974 | 8 这个Project的大致意思是用usb连接到PC。用户可以用PC调节一个数字可调电阻阻值。
I2C用来控制Analog Devices的数字可调电阻。比如AD5241。所以,I2C应该要发送数据
的。
另外,大概用pic675/629开发要多久呢?3,4个星期够了吧。
以前用过8051和Mortorola的DSP。主要用来做采样和控制。数据传输的学校学过,忘了
,没有实际没做过。 |
l*******k 发帖数: 1974 | 9 这个Project的大致意思是用usb连接到PC。用户可以用PC调节一个数字可调电阻阻值。
I2C用来控制Analog Devices的数字可调电阻。比如AD5241。所以,I2C应该要发送数据
的。
另外,大概用pic675/629开发要多久呢?3,4个星期够了吧。
以前用过8051和Mortorola的DSP。主要用来做采样和控制。数据传输的学校学过,忘了
,没有实际没做过。 |
f*****0 发帖数: 489 | 10 sounds like it is one way.
there may be more efficient software solutions. check linear, ti, nxp, maxim
/ dallas or national if you can. I am not aware of any usb->i2c
transceivers but quite a few usb->spi transceivers (max3420) and you can
find plenty of spi-interfaced digital pot.
if you intend to go down the up approach, and has familiarity with 8051, you
may try keil C51 which is a 8051 c development environment. 8051 is a more
complete solution but may be an overkill for this project. with |
l*******k 发帖数: 1974 | 11 It is very helpful.
Thanks a lot, |
l*******k 发帖数: 1974 | 12 It is very helpful.
Thanks a lot, |
e*****a 发帖数: 2 | 13 USB2I2C直接硬件实现USB转I2C接口,无需写任何固件代码,PC机驱动丰富,我手头上
有一个,调试电路非常好使:-) |
e*****a 发帖数: 2 | |