Need help with Schmartboard connection

NoWay

I have a Parallax·schmartboard·with a·Parallax usb prop plug connected to it.· It works perfect and I am able to connect to it via the Parallax Propeller tool software.
I also have a Freescale mc56f8006vlc dsc/microcontroller.· I need to interface the schmartboard with the mc56f8006vlc.· The freescale chip is on a badge used for a security conference.
Here is what I know.· There are labels on the badge to identify some of the Freescale pins, I know that I need to connect to the TX, RX and GND·pins, which are labeled.·What I don't know is can I just use the Parallax USB tap and connect it directly to the·TX, RX, and GND·freescale pins, or do I need to wire the Parallax·schmartboard·to the freescale chip.··To program the·freescale chip I have the Codewarrior software installed, so I just need to figure out how to connect to it. I am having a lot of trouble finding information.· Just for clarification, this isn't the Freescale demo board, it's just the single chip (mc56f8006vlc) used in a circuit board worn as a badge.· Any help is much appreciated.

Thanks
·

kwinn

First, I am going to assume the prop is running at the standard 3.3V, and that the Freescale chip is running at a similar (2.8-3.6V) voltage. I would suggest powering the badge from the schmartboard power supply if possible. I connect the grounds directly and use a ~1K resistors to cross connect TX-RX, RX-TX. No reason you can't take the signals from the USB tap as long as the USB cable is not connected at the same time.

kwinn

PS - It is possible that the logic levels of the serial data from the two chips are opposite polarity, in which case you will need to invert them using either hardware or software.

NoWay

Thank you for the reply.· The badge runs off of a 3v CR2025 lithium battery.
I have tried the method you mention and I can't connect.· I know the Parallax USB prop plug works because I can access the schmartboard with it.· I know the badge works because it lights up as expected. So it must either be·the way I have it connected or the Codewarrior software (I'm not too familiar with Codewarrior, but it seems all of the funtions to read from the Freescale are greyed out).· Can you tell me how to do a definite test once connected to the Freescale chip?· Can I just open up Hyperterminal in Windows XP and get some kind of feedback from the Freescale chip?

Thanks

kwinn

With the 3V CR2025 connection through the 1K resistors should be ok.

re: Can I just open up Hyperterminal in Windows XP and get some kind of feedback from the Freescale chip?

This would depend on what the Freescale software does. If it is written to respond to serial input you should see something. Is it possible the security is set on the freescale chip so the software can not be copied?

NoWay

The link at the bottom has the information about the badge.·The second·photo from the top shows the back of it and the circuit.·It was designed to be "hacked" and in fact there is a badge hacking contest.· So I don't think it's a security setting, but I may be wrong. Clearly I don't have much experience with the Freescale products.· I am tempted to buy the Freescale demo board that contains the same chip to learn more about it.· I guess I will read up more on Codewarrior and find out if there is a diagnostic or some other test to immediately confirm connection with the Freescale microcontroller.· I still can't tell if it's wiring or the software.· Thanks again for your time and input.

http://www.wired.com/threatlevel/2009/07/defcon-badge/

StefanL38

seems to be for really hackers to hack as the firmware is written in C and seems to be quite complex

how about "hacking" off the freescale-chip replacing it by a propeller
demonstrating what a propeller can do ?

best regards

Stefan

CounterRotatingProps

Well Joe Grand certainly won't be posting any help here ;-P

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NoWay

Yeah, I'm not sure why Joe went with Freescale, considering he has a business relationship with Parallax.· Maybe it was cheaper. The hardware hacking kit sold at Defcon included the Parallax schmartboard kit(customized by being black with the Defcon logo) and the Parallax USB prop plug.· Joe provided the code and other software to load on the Freescale using the schmartboard. I wish I could get that far.· I have done projects with the basic stamp and the javelin and sure do wish·Joe would have used the Propeller on the badge.·This year he made very small red, green, and blue leds light up·with the color and intensity based on the frequency of the sound picked·up by a microphone on the badge.· If a certain frequency is received, the leds·start blinking morse code which gives a web site url.· I don't know what the website is yet.·Maybe some of you guys should come to Defcon next year and enter the badge hacking contest. There is was is called a Hardware Hacking Village in one of the Skybox conference rooms.

Here is a link to the Defcon customized Parallax schmartboard if anyone is interested.

http://blog.schmartboard.com/blogschmartboard/2009/07/defcon-17.html

kwinn

Joe probably chose freescale because it is more difficult to hack. I thought you might just be having a problem making the right connections to communicate between the prop and the freescale.

I am afraid I don't have the freescale expertise to help in hacking a system that was most likely designed to be difficult for the unauthorized masses to hack.

Good Luck,

Kurt

NoWay

I finally got it working. It worked with the Parallax USB prop plug connected directly to the Freescale TX, RX, GND pins. I didn't use a resistor. Using Hyperterminal in Windows you can read from the Freescale after resetting it by removing and replacing the battery. So at least I have established that the connection is working. Thanks for your help.

kwinn

Always a pleasure to help out. Congratulations on getting it to work, and good luck with your hacking.