"escuderon" <godfather@datafull.com> skrev i meddelandet 
news:59GdnduXps-9MkzYnZ2dnUVZ_tWhnZ2d@giganews.com...
> I'm in problems!! please Help Me!!!
>
> I'm interfacing an 8051 from Atmel (AT89s8252) with an USB to serial
> converter from FTDI (FT232BM).
>
> The FT232BM is Bus Powered and the 8051 is powered through the BUS too.
>
> The interfacing i use is simply through the UART of 8051 directly to the
> TXD
> and RXD pins of FT232BM.
>
> Just for testing, I've programmed the 8051 t osend a byte to the port
> continuously at 9600,8,n,1.
>
> When the 8051 is connected directly via Serial port (COM1) it works
> properly
> (monitoring data with Hyperterminal), but if it's connected through the
> FT232BM, i only see a character received continuously that there is not
> the
> one I've programmed to send.
>
> The same happens when i use a testing code that only sends to the port
> what
> the 8051 receives, like a Loop. But in this case i only receive garbage
>
> My doubt is that maybe a handshake has to be done when the FT232BM is
> connected, or something like??? please, if you suspect something, tell
> me!!!
>
> Lot of Thanks, and sorry about my English, its very poor!!!
>
> Best Regards, thanks!
>
> Nicolas
>


Why not use an AT89C5131 with built in USB device?
You can get CDC (Communication Device Class) S/W for the 5131!
CDC is also available with the AT91SAM7Sxxx and the AT90USBxxx chips.
No need for extra circuits...

-- 
Best Regards,
Ulf Samuelsson
This is intended to be my personal opinion which may,
or may not be shared by my employer Atmel Nordic AB 

I'm in problems!! please Help Me!!!

I'm interfacing an 8051 from Atmel (AT89s8252) with an USB to serial
converter from FTDI (FT232BM).

The FT232BM is Bus Powered and the 8051 is powered through the BUS too.

The interfacing i use is simply through the UART of 8051 directly to the
TXD
and RXD pins of FT232BM.

Just for testing, I've programmed the 8051 t osend a byte to the port
continuously at 9600,8,n,1.

When the 8051 is connected directly via Serial port (COM1) it works
properly
(monitoring data with Hyperterminal), but if it's connected through the
FT232BM, i only see a character received continuously that there is not
the
one I've programmed to send.

The same happens when i use a testing code that only sends to the port
what
the 8051 receives, like a Loop. But in this case i only receive garbage

My doubt is that maybe a handshake has to be done when the FT232BM is
connected, or something like??? please, if you suspect something, tell
me!!!

Lot of Thanks, and sorry about my English, its very poor!!!

Best Regards, thanks!

Nicolas