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USB hosts hubs transceivers

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I have two USB camera need to connect to PC by one chip. I also need some GPIO to realize simple control logic.


Firstly, I selected the USB Hub----CY7C65113C, but then I found it is not recommend to use in new design.


So I want to change to another way which use USB Host----CY7C67300, two usb host interfaces connected with camera, usb otg connected to PC. See picture as attached.


But it is only a idea, I really don'y know whether it is feasible. Please suggested. Thanks!

3 Replies
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Hello  Wei,


In 67300  there are 2 Serial-Interface-Engines -SIE


                     SIE1--> Host,OTG,Peripheral functions


                    SIE2-->Host,Peripheral functions 


Only one of the functions per SIE can be used at a given instant.Each function is mutually exclusive to another.


For e.g:  When you use SIE1 as Host you cannot use it as OTG or Peripheral. Similar is SIE2.


As per the system diagram attached OTG cannot be implemented in the same chip when 2 hosts are active on SIE1 and SIE2.


In that case  you need to use 2 chips.1st chip for 2 Host functionality and a second chip for  OTG port connected to PC.In second chip OTG port acts as purely  a USB peripheral.


Do you intend to view/copy  digital images from between Camera and PC?Will the cameras be used as Mass storage FAT32 formatted drives to view the content?.




Thanks                                                                                                                                                                                                Narayana Murthy M

First like received Welcome!

In the CY7C67300 datasheet, you can see the Table 3. USB Port Configuration Options in page 3.


There is a option One OTG + Two Hosts. It can configure SIE1 as one OTG and SIE2 as two Host. It seems it is feasible.

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Forgot to say SIE1- 2hosts 1 OTG and SIE2-2 hosts .Assigning 2 Host ports on SIE2 for 2 cameras and other SIE1 acting as OTG (infact peripheral to PC) it is possible as Zhao  mentioned .


You can connect 2 cameras to SIE2 as Mass storage drives .There is a Reference design CY4640(http://www.cypress.com/?rID=14383) in  which


msc firmware folder will do this task.This firmware can talk to FAT32 formatted Pen drives.


It is a combination of USB Enumeration API +  USB Mass storage BOT class API + File IO API + FAT32/16/12 API + Volume management API + UART application N debug Command line API.The total size of firmware is 53KB.


Total available RAM memory in 67300 is 56KB. Remaining 8KB is used by BIOS ROM code(0XE000-0xFFFF).


You need to do the following  to realise this implementation


1. .See the CY4640 1_1 ReleaseNotes.pdf after installing the RDK . Remove unused sections of msc firmware code like UART functions in -cy_printf.o app.o . This will reduce the code around 5KB


2.msc firmware currently works on SIE1 . Please shift the code base to SIE2.You need to replace SIE1 functions and register definitions with equivalent SIE2 entries.


3. Implement peripheral  functionality on SIE2  and GPIO control logic can also be added to this existing code.


It looks like a feasible solution if memory usage is taken care properly. Sorry for the eariler description.




Narayana Murthy M