fig 1. (serial connection)
http://jimmi.zoto.com/img/original/497f1f4fa561690f91354f9fe587c746-.jpg
fig 2. (button)
http://jimmi.zoto.com/img/original/0fc753cda690d505da44329ed14c469c-.jpg
how do i connect this button to serial connections, so it will work
for me?
Whould I use resistor or something? Or maybe I have to use some
additional chip?
Sorry if questions is lame, but haven't done that before.
Any advice would be very helpful for me.
Cheers,
Jim
Since you have only one button, I'd connect it across an output like DTR on
pin
4 and input like DSR on pin 6. It won't swing +v to -v but as it should but
many devices, especially laptops, don't adhere to the standard.
The status register will be what you read for the button push.
Connector pin assignments
http://www.aggsoft.com/rs232-pinout-cable/serial-cable-connections.htm
Specific instructions from a similar box + software to ease the task
http://www.psy.vu.nl/download/menu/xml/eprime_howto_port_com.xml
com1 is at 3F8, its status register is + 4 ports from there or 3FC...Windows
generally make direct port manipulations difficult.
Another good place to visit is Jan Axelson's page, I'd recommend you buy
her book.
I've done something similar making a simple rotation counter. I
connected the RTS to a 10k resistor, then to the switch, and then
to then Rx pin. When ever the switch made contact, jibberish was
put in the serial port input buffer. My program checked the input
buffer on a periodic basis to see if anything was in the buffer.
If there was anything in the buffer, the switch had made conact.
If the buffer was empty, then no switch action.
thanks a lot,
jim