On Oct 23, 2005, at 7:57 PM, Dave Hylands wrote:
> Hi Brian
> On 10/23/05, Chris Baechle <cbaechle@...> wrote:
>> Thank you, that was very helpful. I think I'm straight on that. =20
>> One more
>> question. I searched the wiki and found information, but it's a bit
>> confusing to me. What's the difference between ffuart, hwuart, and
>> stuart? Is it going to affect what type of serial devices I can =20
>> to the gumstix?
> FFUART is the one used for the console. I would only try to use it for
> something other than the console as a last ditch thing.
> BTUART was originally intended to hook up to the the Bluetooth chip,
> but the flow control didn't work very well, so the HWUART was used
> instead, which unfortunatley leaves the BTUART lines unavailable.
We are revising the gumstix though to bring these lines to the 60-pin =20=
connector if there's no bluetooth module on the gumstix, so non-BT =20
gumstix will have a new UART available soon.
> The original waysmall boards had FFUART and HWUART brought out. The
> new waysmall boards have FFUART and STUART brought out.
> Other than that, I'm not sure what the differences are, perhaps
> somebody else on the list knows?
=46rom the PXA docs:
10.2.1 Full Function UART
The FFUART supports modem control capability. The maximum tested baud =20=
rate on this UART is
230.4 kbps. The divisor programmed in the divisor latch registers =20
must be equal to or greater than
10.2.2 Bluetooth UART
The BTUART is a high speed UART that supports baud rates up to 921.6 =20
kbps and can be
connected to a Bluetooth module. It supports the functions in the =20
feature list, (see Section 10.1) but
only supports two modem control pins (nCTS, nRTS).
10.2.3 Standard UART
The STUART supports all functions in the feature list (see Section =20
10.1), but does not support
modem control capability. The UART=92s maximum tested baud rate is =20
230.4 kbps. The divisors
programmed in divisor latch registers must be equal to or greater =20
HWUART: max baud rate of 921600, and supports full hardware flow =20
control (see PXA docs chapter 17 which is all about the HWUART).