connect avr rs232 to usb of pc ?

[omidsht]

hi ,
i want to convert the avr rs232 to usb of pc , because i need to use the baud rate more than 115.2kbps of avr rs232 (ex . 230.4 kbps) and pc does not support that , so i want to connect rs232 of avr(atmega16) to usb of pc to have higher baud rate , what shall i do and which IC should i use ?

waiting for your guide

omid

[8K51]

Hi
FT232 from FTDI does the job.
http://www.ftdichip.com/Products/FT232BM.htm

Single chip USB <=> asynchronous serial data transfer
Full handshaking & modem interface signals
UART interface supports 7/8 data bits, 1/2 stop bits and Odd/Even/Mark/Space/No Parity
Data transfer rate of 300 Baud => 3M Baud (TTL)
Data transfer rate of 300 Baud => 1M Baud (RS232)
Data transfer rate of 300 Baud => 3M Baud (RS422/RS485)
384 Byte Rx buffer/128 Byte Tx buffer for high data throughput
Adjustable Rx buffer timeout
Fully assisted hardware or X-On/X-Off handshaking
Available in standard 32 pin LQFP (FT232BM) and lead(Pb)-free LQFP package

Regards

[s_ch]

FT232R from FTDI. Have minimum external elements (no need external rezonator,eeprom).very easy circuit.

[zetd]

Yes, FT232XX, is best choice,

also there is an AVR based project, which translate USB <> RS232, called AVR Communication Device Class (CDC). no other chip to process USB stack, processing is done by software trick.

check this, but may not satisfied your requirement :
http://www.recursion.jp/avrcdc/
http://www.cesko.host.sk/IgorPlugUSB/IgorPlug-USB%20(AVR)_eng.htm
AVR309 http://www.atmel.com/dyn/resources/prod_documents/AVR309.zip
http://www.obdev.at/products/avrusb/index.html

[8K51]

AVR only USB from 'obdev' is good for HID class but very limited for CDC serial class.
-CDC on USB1.1 is not standard, so not well supported by some OS.
-4800 bauds is max speed : http://www.recursion.jp/avrcdc/

If FTDI package is a problem then DIP PIC 18F2550 could serve.

[omidsht]

thanks to all.
if i use ft232r , then which software i should use in pc to send and receive data from usb port ?
omid

[8K51]

Your chip will install a new serial port (virtual port), so every terminal (hyperterminal....) will send/get data !
CDC profile will work on XP, Linux...... without special software.
You just have to put the good driver at first time.
(Many USB to RS232 adaptators use FT232, others uses a Prolific chip.)
Regards

[omidsht]

thanks 8k51
do you have a cdc or ft232 project to give me as an example ?
omid

Your chip will install a new serial port (virtual port), so every terminal (hyperterminal....) will send/get data !
CDC profile will work on XP, Linux...... without special software.
You just have to put the good driver at first time.
(Many USB to RS232 adaptators use FT232, others uses a Prolific chip.)
Regards

[id2]

You can use TUSB3410 (from TI) too,
it's same function as FTDI
I use both FT232BM and TUSB3410 to make my programmer
there are no any problem

[Martin]

Other type of conection AVR to USB you can found here
http://www.embedded-projects.net/index.php?page_id=165

[vibrex2007]

Try it. SILICON LABS CP2101 or CP2103. No XTAL required. The best!  www.silabs.com/public/documents/tpub_doc/dsheet/Microcontrollers/Interface/en/CP2101.pdf

[whoami]

FTDI FT232RL use a few component. easy to implement.

[demorphica]

try sunrom.com, they have a tiny usb converter board, which you can connect to avr using db9 plug, and usb patch cable at other end. you will also get libraries and code from them