[En-Nut-Discussion] UART flow control

[Harald Kipp]

Tarmo,

In fact there are some changes planned. One is handshake
(HW and SW), the other part are some optimizations like
splitting interrupt routines for UART0 and UART1.

On the new Rev-F boards, which we started shipping now,
two pads are on the bottom side for connecting PD2 and
PD3 to the RS232 driver. This has been changed from
Rev-D boards, which use PE2 and PE3.

Sorry for the trouble that this change may cause. Using
PE2/PE3 offers the ability to use either RTS/CTS or
UART0/UART1 on the DB-9 connector. Using PE3 for handshake
input was a bad idea, even for the previously used ATmega103.
The handshake input typically requires an interrupt. It should
be not too difficult to modify existing boards. And the new
include/cfg subdir will allow to use different hardware
designs. I'd recommend to move a copy to mod/include/cfg and
modify that copy.

You can check the schematics of Rev-F at
http://www.ethernut.de/pdf/enhwm16.pdf

Harald