[Gumstix-users] BT on BTUART

[Benny S. <ben...@ma...>]

Hi

I have to use both serial ports on the waysmall so I'm still trying to ge=
t=20
the BT module working on the BTUART instead of the HWUART.
Someone from the list did send me a data sheet for the ROK 104101 module,=
=20
but in that data sheet I can't find any specific things about the UART=20
except from the fact that UART 1 has a 128 bytes FIFO, but nothing regard=
ing=20
how many bytes it will accept after setting RTS low.



The data sheet is marked:

-------------------------------

Preliminary Data Sheet
EN/LZT 146 130 R1C
=A9 Ericsson Microelectronics AB, May 2002

-------------------------------

If someone should have another datasheet for the module and did not sign =
a=20
NDA then please send it to me.



Until now I have tried different things with limited success. I have amon=
g=20
other things tried to limit the use of the TX FIFO to one byte (I will fi=
rst=20
insert a new byte when the previous has been send). With this approach a=20
change on CTS should prevent further bytes to be transmitted (normally up=
 to=20
64 bytes could be transmitted after the BT module say "stop").

It does work better, but still I see the BT crash occasionally. Another r=
eal=20
"funny" thing is that CTS on the gumstix change state every time I send j=
ust=20
one byte to the BT module. I thought it was an error in the serial driver=
,=20
but when I use the HWUART on the waysmall it seems to behave as expected.



Suggestion to what to do (and or a datasheet which might explain the funn=
y=20
behaviour of the flow ctrl signals) will be appreciated.





BR

Benny=20