Serial Communication Problem

Alright, so I prototyped a project I’m working on with my arduino uno R3; everything checked out. Then I bought a 5v 328 arduino pro mini for casing in the actual finished project and a CA-42 nokia phone cord to hack into an “FTDI” cable for uploading the sketch onto the pro mini. I soldered everything together inside the cable for the mod, installed the correct drivers successfully (took forever), assigned the cable to an empty COM port, plugged the cable into my arduino R3 (i’m using the R3 to trouble shoot the cable), and uploaded a sketch using Arduino IDE 1.0.1. The arduino powers up, but upon upload I get the common communication error: avrdude: stk500_getsync(): not in sync: resp=0x00.

This is my cable:
http://www.dealextreme.com/p/ca-42-compatible-usb-2-0-data-cable-for-nokia-2110-2112-2115-more-45715

These are the tutorials I used:

I check’d and made sure all my solder joints have proper continuity and don’t touch. I “loopback’d” the RX and TX pins on the arduino R3 by itself and they check out. I then loopback’d the RX and TX pins on the actual “FTDI” cable using hyper terminal and they check out. When I alligator clip the RX end of the “FTDI” cable to the arduino’s TX pin and the TX pin of the “FTDI” to the arduino’s RX pin the serial monitor show’s no communication. They both check out separately, but when I put alligator clips between the two they no longer communicate…i’ve tried multiple alligator clips and multiple COM ports as well!

Not sure if this is in the right place, but please heeelp!!! I can post pictures if need be.

Funny how saving a few dollars ends up costing so much time, isn't it?

Slump: When I alligator clip the RX end of the "FTDI" cable to the arduino's TX pin and the TX pin of the "FTDI" to the arduino's RX pin the serial monitor show's no communication.

What about Ground?

I tried using arduino IDE 0023 and to get rid of the sync error, but the serial monitor still shows nothing upon loopback and the actual sketches don’t show signs of upload.

There are 5 solder pads on the FTDI cable; VCC->5v pin, TX->RX, DTR->Reset, RX->TX, GND->GND

Is it possible to upload sketches to a 5v 328 pro mini using an R3? I've heard conflicting responses on this and upon trying it I get the same 0x00 sync error.

Slump:
Is it possible to upload sketches to a 5v 328 pro mini using an R3? I’ve heard conflicting responses on this and upon trying it I get the same 0x00 sync error.

If you remove the ATmega328 from the board.

The first time I built an amp I accidentally put the IC in the DIP socket wrong, but noticed it before I turned it on; when I went to switch it around it ended up being harder to take out then I thought. With a quick jerk I yanked it free and bent every pin of the IC with it, rendering it useless!!

I'll try and take it out carefully, but I read that taking it out shouldn't matter, it will just program both chips instead, which is no problem because the uno R3 is very easy to re-program. But of course there is the sync error, do you think the uno chip causes that?

Slump: but I read that taking it out shouldn't matter, it will just program both chips instead, which is no problem because the uno R3 is very easy to re-program. But of course there is the sync error, do you think the uno chip causes that?

Don't believe everything you read on the Internet, because that is not true.

avrdude must be able to read from the chip. Two chips talking at the same time are going to disrupt the communication.

ha, yea I guess the internet can be hit-or-miss. So do I just plug in 5v, GND, RESET into the pro mini and then UNO TX->Mini RX and UNO RX->Mini TX. Click Arduino as ISP, and 5v 328 pro mini from the drop down in the IDE? I'm taking out the chip right now, but it's putting up a fight...

Slump: So do I just plug in 5v, GND, RESET into the pro mini

Yes

Slump: and then UNO TX->Mini RX and UNO RX->Mini TX.

No. Connect TX of the Uno to TX of the Mini. Same for RX.

Slump: Click Arduino as ISP, and 5v 328 pro mini from the drop down in the IDE?

No. You aren't doing this as an ISP. You are using the Uno's on-board Serial to USB converter. So set the board type to 5V Pro Mini and the Serial Port to whatever your Uno normally is, then click upload.

Still getting the sync error 0x00; serial monotor shows no communication. I remember reading somewhere that the UNO has an upgraded chipset which rendered it useless for this and that you can only use older boards. Hopefully it’s just another internet myth…

Slump: I remember reading somewhere that the UNO has an upgraded chipset which rendered it useless for this and that you can only use older boards. Hopefully it's just another internet myth...

"Upgraded chipset" doesn't make sense. Sounds like another under-informed comment. It was difficult (impossible?) to use the SMD-Version of the Uno in this manner, since you couldn't remove the chip.

Given how the Auto-RESET works, it is possible the Pro Mini isn't being reset correctly. You may have to practice a few times manually reset the Pro Mini. Press the RESET button (on the Mini) 1-2 seconds after the "Binary Sketch Size" message appears int the IDE.

Still no use, but i'll keep trying to press reset at the right time, although I've been doing this maneuver to no avail with the CA-42 cord as well.

You’re far more patient than I. I would have placed an order for a proper FTDI cable quite some time ago.

Haha, well 20 days ago when I had money to spend the DIY cable from china didn't look to hard...regretting that decision now though.

This is the guide i'm using: http://arduino.cc/en/Tutorial/ArduinoToBreadboard

This is the pro mini:

There are 2 TX0's and RX1's.... Also isn't GRN for auto-reset?

I got good news and bad news. I FINALLY GOT IT WORKING!!!!!!!!!!!!!!!!!!!!!!! Unfortunately, I have no idea why it works now. It's a catch-22 because i'm a philosophy major and being accidentally right is just as bad as being wrong, haha. Although, I was trying to isolate my problem very scientifically so that I could explain what went wrong in my case and how to fix it just in case others encounter a similar problem, but oh shwell, I'll take this win and buy a breakout board for next time instead!

Now to put my atmega back in my uno and hope that it's alright...

[quote author=James C4S link=topic=119193.msg896896#msg896896 date=1345353578] Funny how saving a few dollars ends up costing so much time, isn't it? [/quote] And you may be right there, but this was actually a very good learning experience for me! I've learnt a lot from troubleshooting this (although I do concede that it was frustrating as all hell) and am now ready to make my own "arduino" for my next project. (and of course i'm ready for the headaches that go along with that as well :p )