[En-Nut-Discussion] Ethernut 3.1 RS232 hardware handshake

[Paul Govers]

Hello,

i am working on a application for a ethernut 3.1 that has to read data from RS232. I experiance some problems with reading data from the rs232 port.
i have running the demo application rs232d, so all data that received on the rs232 port will be displayed on the TCP channel. When i connect my laptop to the rs232 port of the ethernut and make a tcp connection to the tcp service on the ethenut board i see al the data (thats on the RS232 port) on the TCP channel. it works just fine!

but now i want to connect my Remeha Heating system to the ethernut with a serial cable, both devices has a comport. When i connect my laptop to the remeha heating system i get data from it(rs232|9600baud|no flowcontrol), i can see the data with a serial program called "Advanced Serial Port Terminal". But when i connect my remeha heating system to the ethernut i receive nothing :-(  i connected a scoop to pin 2 and pin 3 but still no data

iam using a fully wired nullmodem cabel, and i allways connect with 9600 baud, with no flow control.

i think the solution can be found to enable hardware handshake on ethernut.
i found the webpage http://www.ethernut.de/nutwiki/UART_Hardware_Handshake where there is a description how i can enable hardware handshake, but my nut/os configurator has other settings the the wiki page. i have a option to select "Harware Handshake" but this one is grayed out, so i can't select this option.

the question is how i can enable hardware handshake on my ethernut 3.1 board?
or maybe someone have a great tip for me?

Greetings
Paul