A tour inside the RC
 

I posted this already, but the host went down and the forum software wouldn't let me edit the URLS so i am posting it again. I will try to get a mod to delete the old thread

click any of the pics for a high res version
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I did some warranty vioding on the RC. Here are the results:
Here you can see the Hidden ISCP headers for the master and user processor as well as some pins labled TX and RX. I presume this is a tap to the data to the radio modem or a serial port on the master proc. Also visible is an unsoldered mystery header. I will trace these as well as the TX and RX pins when i have time. You can also see that ther is space for 3 more LEDs. That thing in the top middle is the user processor. Those two dimpled chips on the left are buffers which allow the mater processor to disable the user processor from controlling the relay outputs.



Here you can see the back of the board. Nothing too interesting here. More or less one big groundplane.




Here is an overview of the whole thing. At the right of the pic is the power supply circuirty which consists of three regulators, some diodes so that it doesn't explode when hooked up backwards, and some auto resetting fuses. The top regulator provides power 5v power to all the external pins such as the digital and analog IO ports. The middle regulator provides power to the internal curcuits of the RC itself. The circuitry which switches from main to backup power is at the top right around the orange fuse. The bottom regulator powers the OI when it is connected to the RC through tether. Intermingled with the power supply circuitry are the rs232 and rs485 converters for the program port, tether and the radio modem. In the middle of the image you can see the master processor and the user processor. They are the big square chips. The one on top is the master. It looks like they share a single crystal oscillator as a clock source(the little metal thing to the top right of the master processor.

Re: A tour inside the RC
 

Hey Rickertsen2, thanks for all of the great pictures lately, I've always wanted a peek inside of the RC but my team would kill me if I opened it up.

Re: A tour inside the RC
 

If you have the right kinda of paper for you printer you can print new stickers. :D

Re: A tour inside the RC
 

Except you would most likely be asked by an inspector to remove the stickers to show you're using the standard RC.

Re: A tour inside the RC
 

And why bother to use an old RC when a purty new one will be arriving in the mail shortly?

Re: A tour inside the RC
 

nicely done once again :D I always wondered what was in there...

Re: A tour inside the RC
 

Do you still have access to the guts of that RC? Could you see what processor pins the Master and User headers go to? I am curious what their function is.

Here is a link to the datasheet for the processors if anyone is interested:
http://robotics.dyndns.org/PIC18F8520.pdf

Thanks for posting the pictures!

Re: A tour inside the RC
 

My best guess would be ICSP, which would be RB5, VCC, GND, RB7, and RB6. Not necessarially in that order.

Re: A tour inside the RC
 

Pardon my ignorance, but what does ICSP stand for? :o

Re: A tour inside the RC
 

In Circuit Serial Programming, iirc.

Re: A tour inside the RC
 

Thanks, Google confirms this. (If you just type in ISCP, a whole bunch of unrelated stuff comes up).

Re: A tour inside the RC
 

They are ISCP. They use the standard pinout. I traced them already. For those of you who do not know what ICSP is it stands for In Circuit Serial Programming. It allows you to hook up a PIC programmer and upload code to a PIC while it is in a circuit. There is one for the master processor and one for the user processor.

I figured out what the RX and TX pins were, but i don't remember. I think it is a tap on the link btw the master and user. My question is what the blank space that looks like there should be a connector is for. I seem to remmeber the pins going to some GPIO on the master processor.

I still have the thing disassembled in a drawer if anybody wants me to elaborate on anything.

Re: A tour inside the RC
 

Could you tell me what the pinout on the Competition port is? I have heard rumors that IFI uses a serial interface; just curious if there were pins going to a UART or something.

You could try booting it up with an oscilloscope on each of those pins and see if they are even active or not. Maybe they're just for future expansion, and the software doesn't even use them right now.

Re: A tour inside the RC
 

just curious while you have it apart can you tell me which pins in the competition port are the power inputs? I know they are there somewhere but the team would kill me if I removed those d@mn stickers!!! thanks in advance for any help

Re: A tour inside the RC
 

Need help with RC "initializing".

The Program State LED on the RC is solid yellow and can't get it reset
The RC Mode LED is solid yellow

The Code Error LED on the OI is solid red

Nothing seems to be working. Can't download program to RC. I did notice that the "User code" in the display window of the OI reads "012".

Any help is appreciated.

Re: A tour inside the RC
 

http://www2.usfirst.org/2006comp/oth..._Practices.pdf

Check out page 29.. I think it will help :)