Let's Make Robots!

Mr. General questions

I've been looking into building a robot, and I found the Start Here robot and this site.  I liked it, but after looking around more I discovered the Mr. General kit, which seems to be more versatile for about the same price.  It's also more complicated and doesn't come with a handy step-by-step set of instructions to completion.  I'm not that experienced, but not a complete novice at this sort of thing-- I've made a 555 based dice roller and a (mostly nonworking due to wheel issues) simple light follower.  I can solder, read resistors, and know not to put LEDs in backwards.  I've done BASIC programming, but it was years ago in high school.

I've basically got two questions:  First, what sort of difficulties am I going to run into with the Mr. General that I'd avoid with the Start Here Robot. Second, know I need a CPU, and I was planning on getting a PICAXE chip (what version would be best? 28x1?) and a cable for it.  What else will I need?  Do I need a recieving plug for the USB cord?  Any other parts to connect the chip to the servos or the sensors?  I've got resistors, diodes, and caps. 

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I bought an Atmega328 with the optiboot bootloader installed.  The Mr. General kit came with a USB card (Silicon Labs CP2102) whichseems to be working fine.  I can see packets moving up and down with serial io monitor.  ONly problem is the Arduino IDE won't upload a sketch.  I always get the "avrdude: stk500_getsync(): not in sync: resp=0x00" error. I have been asked for a photo of the wiring, and am attempting to include the link as instructed.  If it isn't readable, here is the link (minus the https prefix): dl.dropboxusercontent.com/u/4203055/IMG_0810.JPG.

Thanks,

Bob

Breadboard Wiring 

I purchased the Mr. General kit along with an Atmega chip, but there was no indication of whether or not the chip had a bootloader already on it.  I'm very new to this, so I would like a link to the information that will let me a) find out whether it's there or not and b) burn it on if it's not there.

I'm sure this seems like a stupid question, but I've tried to research it and not had any joy.  The large number of variations is confusing and I would like something that will work with the Mr. General setup.

 

Thanks.

Bob

Originally DAGU sold the kit with an ATmega8A that had the bootloader installed. However some distributors have bought the kit without a processor and then added their own so It is hard to say if the bootloader is installed or not.

Start by looking at the tutorial here: http://letsmakerobots.com/content/understanding-mr-general-robot-kit

Check the wiring diagram to see if you have wired everything up correctly.

it will help if you post a high resolution photo of your wiring and the USB interface you are using.

Here's the photo. The USB interface is the one that came with the kit. I get a red LED on the USB board and on the robot when I plug the cable into it. The Serial port monitor shows packets both directions, but Arduino IDE won't do the upload.

Sorry, no photo. Start a new forum topic then you can add photos.

And it's HUGE.

Ok, must be a China thing, I can only see a comment.

Further to this issue, I have determined that the Atmega chip is actually an Atmega328 and that it has an optiboot bootloader installed.

I still can't get the Arduino IDE to upload a sketch though. At the end I get "avrdude: stk500_getsync(): not in sync: resp=0x00" which seems to have as many causes as there people with this problem.

I have a monitor on the serial port and packets are being exchanged, so I know the cable is good and the USB interface is communicating.  I am using the Arduino Uno board selection.

Any help would be appreciated.

Thanks

Bob

Try swapping the tx/rx pair.