How to support two (dual) USB ports?

[Demon]

I'm curious why complicate matters (that's IF a Pic exists that has dual USB)?

Why not use a master PIC that supports the Wifi module, and have it send messages to two 18F4550 (or whatever USB Pic you prefer)?

Robert

[gadelhas]

I think there is no PIC with 2 UBS, however you can use the serial port and a converter like FTDI, or any other.

[ScaleRobotics]

Curious if you can tell us a little more. Like others have said, either multiple USB PIC chips, or one PIC USB + something like this: http://www.maxim-ic.com/datasheet/index.mvp/id/3639

[rsocor01]

The USB channels option in the Microchip Advanced Part Selector, MAPS, only has the option of 1 USB channel per chip. Why don't you use two 18F4550 like Robert suggested above?

[jellis00]

The USB channels option in the Microchip Advanced Part Selector, MAPS, only has the option of 1 USB channel per chip. Why don't you use two 18F4550 like Robert suggested above?

Thanks for that...I didn't think of using MAPS to see if there was a PIC chip with dual USB. Since there isn't I guess my only choices are as follows:

1) Two PIC 18F2550 chips that each manage a USB port, and one of them to also collect the data from the otherone and to send both data elements to the WiFi module for transmission to the internet.
OR
2) Two MAX3421E Chips for thetwo USB ports and a PIC chip to collect the data from both MAX3214 chips and to manage the iWiFi module transmissions.

Have any of you actually created an app with one or the other of these approaches? Which approach do each of you think is the easiest to implement? I have a lot of experience with 18F2550 but no experience with MAX3421E so I tend to think I should go with 18F2550.

[gadelhas]

HI;

I made it with one 18F4550 using the USB module and one CP2102( UART<->USB converter).

[Darrel Taylor]

Why would you need two USB ports?
Are you connecting your device to two computers at the same time?

If you are thinking of plugging USB devices into your project and relaying the information to the ethernet adapter ... you can't do it with the on-board USB peripheral.
PIC chips don't do USB "Host" mode. At least not the PIC's that PBP can work with.

I think your best bet is the VNC2 - Vinculum-II Programmable USB 2.0 Host

[jellis00]

Thanks for that, Gadelhas. I reviewed the CP2102. It looks like it is a it is a bridge between a USB host and UART microcontroller like a PIC 18F2550/4550, in a similar manner to the VFC chips recommended by Darrel Taylor and spcw1234 in their below postings. Do you concur?

I guess a USB host bridge is the way I have to go to get two USB ports supported to meet my requirement. My decision on which chip to use (CP2102 or VNC) then boils down to which is the simpler to program and implement. Since the VNC chips can be provided with a pre-compiled firmware to support different USB interfaces, that is definitely a speedup on my development. However, if you already have code that implements the USB interface between an 18F4550 and CP2102 and are willing to share the code, that would be a rapid development process also.

Are you willing to share your code? I don't need the pincount of an 18F4550, so would probably use 18F2550 as smalleer chips, but the code should be almost identical.

Regards, John