Soft USB on PIC

[ldril]

Hi!

There is a project that uses an Atmel chip to communicate with a PC on USB. All the communication is handled in software.

The link is: http://www.cesko.host.sk/IgorPlugUSB_RS232/IgorPlug-USB%20(AVR)%20RS232_eng.htm

Does anyone know of a similar project using a PIC? The user says PICs are too slow for this, even when slighly overclocked. Has anyone tried to overclock a PIC more agressively? I've seen an account of a 20MHz PIC that seemed to run fine at 36MHz. Do you think 40MHz is possible?

BR,
ldril

 

[Matt(Pic progger)]

Hello,

The 18F452 has a clock quadrupaling (is that spelt right??!!) feature on it, this is rated up to 10Mhz (int clock 40Mhz), so you may be able to hammer this some more, I remember talking to a guy a PIC seminar about 5years ago that was running PIC's at 50Mhz (the 4wire powered can varity of xtal, like you seen on PC Mobo's) he said he had to run the PIC at 7V to make em work :wink:

The 452 has no usb uart tho, let me know please if you/anyone has any usb code for a standard PIC I could do with some direction....

 

[gtrman1992]

How about the USB-UART chip CP2101EK. It transparently gives you USB using the PICS UART.

 

[tavib]

:lol:
You can use a PIC with USB support build in like PIC16C745/765 but this
PICs have support only for low speed mode USB(up to 1.5Mb/s).
As a better alternative you can use an external chip special designed for offer USB support, like FT245BM this is USB to parallel which support low and full speed USB mode up to 12Mb/s. Your app view this chip as a 8 bit bidirectional parallel port, and the chip resolve inside all USB comunication