usb microcontroller with software uart without interrupts

[Jens Bretschneider]

Hi,

has anybody ever tried to write a *software* uart (txd & rxd, using any
gpio-pins) for an usb microcontroller (e.g. TI TUSB3410) *without* using any
external interrupt lines? Is this possible for at least 9600 baud?

Jens

 

[Al Klein]

has anybody ever tried to write a *software* uart (txd & rxd, using any
gpio-pins) for an usb microcontroller (e.g. TI TUSB3410) *without* using any
external interrupt lines? Is this possible for at least 9600 baud?

That would depend on the clock speed, among other things.

 

[Jens Bretschneider]

has anybody ever tried to write a *software* uart (txd & rxd, using any

That would depend on the clock speed, among other things.

Yes, certainly... I've not yet decided which µC to use, so if anyone already
tried this....

Jens

 

[Jens Bretschneider]

Hi Mark,

thanks a lot! I think I'll give it a try.

Jens

 

[Jens Bretschneider]

Hi,

one more question:

On the 8088 project, I had this problem (three bi-directional serial
ports,
and *no* hardware UARTs - only one with unsolicited inputs, though). I
set
up a tight foreground loop, and anytime I saw the first bit of a
character,
I dropped everything else and went to read it in.

Did you continue sending a character if you were "in the middle of one" as
soon as you noticed an incoming character, or did you stop sending
immediately and start sending the character again after receiving a complete
character?

Jens

 

[Jens Bretschneider]

Hi Mark,

thanks a lot for your helpful suggestions!

Jens