USB slave <-> serial conector chip - Raspberry Pi Forums

hi,

i'm trying program raspberry 2 usb slave.
(like other people on net, nobody seems have succed yet ...)

need handle full usb protocol negociation => create descriptors myself !
i've read many things usb protocol, etc ...

so here know :
pi can't used slave, because of hardware (usb ports connected hub, forcing host mode)
=> there usb otg port (the mini usb port in fact) : pins not connected , used, neeed hardware modification on board itself, ... not solution me.

usb on dead, pi has serials interfaces (i2c , uart @ least).
thinking connecting 1 of these "magical external chip" (here trick) convert serial usb
=> many chips (ttl cable example), theses handle usb protocol themselfs (needs driver on windows, etc ...)
=> not need.

need teensy (see there : https://www.pjrc.com/teensy/) : can used create usb peripherical , let user program full usb protocol himself. that's perfect, i'd programm full stuff on raspberry.
may have understood teensy have serial port too, maybe like
pi <= serial => teensy <= usb => ...
i'm looking simpler.

i again : need simple bridge between uart & usb : no intelligence : receive 1 side, transmit other. that's all.

may have found these maybe stuff, understood :
http://www.microchip.com/wwwproducts/de ... e=en533924
http://www.st.com/web/catalog/sense_pow ... 4/pf122777

i'm not sure that's need ...

know chip / card stuff ?

ps :
note i'm experienced in computer programming, kernel stuff , drivers not problem.
sorry many grammar mistakes may/must have done : french guy talking ! feel free correct them.

the rpi model & a+ not use usb/lan hub on usb bus

https://www.raspberrypi.org/documentati ... /readme.md

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