free the rx/tx on fio

hello everyone, I am currently doing something with xbee and arduino fio. here i have a question about how to free the serial communication while xbee is still on the fio board.

we all know that when xbee is on the fio board we cant write any sketch to the board. I want to keep the xbee still on while using RXI/TXO pins is also possible. so I cut the pin 2 and 3 of the xbee and connected them to the d3 and d3 pin on the fio board. I plan to use the softwareserial library to transmit xbee signal.

however after my soldering the uploading still failed. the message is “avrdude: stk500_getsync(): not in sync: resp=0x00”

It would be great if someone could show me what’s wrong with my plan and why it is not working.
Thank you so much!

here is the pic.(ignore the 3 wires I held in my fingers, they r for LEDs,:P)

Did you also cut the DTR line going to auto-reset? Perhaps that is interfering with the reset from the serial cable.

hi john,

no I didnt cut that. If i did that, will the xbee still be transmitting data?

thank you !

jifei:
No I didnt cut that. If i did that, will the xbee still be transmitting data?

Yes. The DTR signal is only used to reset the Arduino so you can do an upload through the XBee. If the XBee is disconnected from the serial pins you might as well disconnect the DTR signal too because you wouldn't be able to upload through the XBee anyway.

hi John

I just removed the DTR pin. however I still got the same error. :frowning:

when I try to write the sketch to the fio, only the TX blinks(red) the FTDI adapter. the RX does not, and after comes the error "avrdude: stk500_getsync(): not in sync: resp=0x00".

any other suggestions?

thank you!

What serial cable are you using? It sounds like maybe the auto-reset isn't working. Try a manual reset (hold down the reset button until you see the RX light blink).

hello john,

what do u mean by “hold down the reset button”? should i do it while uploading or before? I tried both but that didnt help much.

here is the serial cable

any other ideas?

thank you :slight_smile:

jifei:
any other ideas?

Hold down the Reset button.
Click on the Upload icon.
When you see the RX light blink, release the Reset button.

hello John
Thx again for the reply

I did exactly what you mentioned. however I still got the same error.
the DTR pin is the pin 9 on the xbee right? I think I?cut the correct pin.

johnwasser:
Hold down the Reset button.
Click on the Upload icon.
When you see the RX light blink, release the Reset button.

or do I need to put the dtr pin back when I’m doing the manual reset?

jifei:
hello John
Thx again for the reply

I did exactly what you mentioned. however I still got the same error.
the DTR pin is the pin 9 on the xbee right? I think I?cut the correct pin.

From the FIO schematic it looks like they get the DTR signal from the DIO3 pin (17) not the DTR pin (9).

The schematic shows a jumper of some kind between XBee pin 17 and the DTR line. I don't see it on the picture of the top of the board so it may be on the bottom.

Hi Jifei,
how about using wireless programming instead?
Have a look at the Fio programming tutorials if that would work for you:

(You have to scroll down to the Wireless Programming section)

Cheers,
Kofi