Society of Robots - Robot Forum

Electronics => Electronics => Topic started by: mr_kobayashi on April 12, 2007, 11:19:02 PM

Title: $50 Robot - Problem with Connecting Chip to PC
Post by: mr_kobayashi on April 12, 2007, 11:19:02 PM
Hi,

I'm trying to build the $50 robot pretty much following the instructions exactly, except I'm using a 9V battery for the circuit and 4xAAs for the servos. I've finished building the circuit and I'm relatively confident it's OK because I used a multimeter on it and its reading 9V on the sensor power bus and 5V on pin 1 of the AVR ISP connector.

The problem now is that when I connect the cord into the serial port of my PC nothing happens. I'm using the AVR ISP kit, the one where there is a cord connecting my chip to the kit, then another cord connecting the kit to the PC via the serial port.

So I open up AVR Studio, follow the instructions in Step 4 then I click on 'Connect to the Selected AVR Programmer' and it can't find the connection!

I'm sure the cables are connected and lined up properly as in Pin 1 aligns with Pin 1, etc... I've checked this a dozen times.

Any ideas on what is going wrong?

Thanks
Title: Re: $50 Robot - Problem with Connecting Chip to PC
Post by: ed1380 on April 13, 2007, 05:31:57 AM
Are you trying to connect with ponyprog2000?

I'm having the same exact problem with ponyprog2000.
Title: Re: $50 Robot - Problem with Connecting Chip to PC
Post by: JonHylands on April 13, 2007, 06:50:52 AM
I've done a number of AVR boards from scratch over the last couple months, and the biggest problem I've run into is the programming header. Its really easy to screw it up.

I almost never get it wired correctly the first time. Heck, for my first IMU board, I had a couple copies of a professional PCB printed with two of the pins in the programming header swapped.

Take a piece of paper, and write down exactly which pin on the programming header is supposed to be what. Then figure out (from the datasheet) which pin on the AVR chip that corresponds to, and write that down as well. Then take your multimeter, in continuity mode, and check that the right pins on the header are connected to the right pins on the chip. Finally, make sure the "orientation" of the header is correct.

(http://www.bioloid.info/10-pin-AVR.png)

- Jon
Title: Re: $50 Robot - Problem with Connecting Chip to PC
Post by: mr_kobayashi on April 13, 2007, 05:09:18 PM
Thanks for the help but I've checked the pins with a multimeter and made sure it lines up with the schematic in the instructions... its a kit so it's pretty easy to follow and hard to make mistakes on that part of the circuit. :)

It STILL doesn't work though... any more ideas? Oh and "ed1380" I am not using PongProg2000 because I have the AVR ISP kit so thats not needed.
Title: Re: $50 Robot - Problem with Connecting Chip to PC
Post by: JonHylands on April 13, 2007, 06:50:20 PM
Download AVR Studio 4 (if you don't already have it), and try programming from there. It typically gives you much better diagnostic information.

- Jon
Title: Re: $50 Robot - Problem with Connecting Chip to PC
Post by: mr_kobayashi on April 14, 2007, 12:38:09 AM
Download AVR Studio 4 (if you don't already have it), and try programming from there. It typically gives you much better diagnostic information.

- Jon


Yes that's the problem. I have AVR Studio 4 and when I click on "Connect to the selected AVR Programmer" it doesn't work because my PC isn't recognising the serial port connection. I'm sure the problem is not with the serial port... I've checked it and it is clearly on COM1, I suspect it is to do with either the chip, the AVR ISP kit or the cables.
Title: Re: $50 Robot - Problem with Connecting Chip to PC
Post by: Admin on May 05, 2007, 01:28:26 PM
(sorry for the delay, still going through messages since my trip)

Did you solve the problem yet?

Does the green LED on the AVR ISP light up when everything is plugged in and turned on? If not, there is a problem with your circuit. If it does, there is a problem with your computer connecting to the COM.

Quote
I used a multimeter on it and its reading 9V on the sensor power bus and 5V on pin 1 of the AVR ISP connector.
The sensor bus should read 5V, and the servo bus should have the same voltage as your batteries. Is this what you meant?