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Unread 24-11-2003, 09:34
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Sachiel7 Sachiel7 is offline
<Yes I managed to flip it
AKA: Shayne Helms
FRC #1132 (RAPTAR Robotics)
 
Join Date: Sep 2002
Rookie Year: 2002
Location: Richmond, VA
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Sounds cool.

Quote:
BTW - If you right-click on the joystick it recenters both axis.
Heh, I just figured that out last night. Helps alot!
I have a few questions though:
What did you use to program this?
I'm trying to understand the communications a bit more. I don't have very much experience in serial or COM communications at all. From what I understand, the PC puts together a data packet of all 4 joysticks. This is 8 bytes in length. I'm assuming it's 2 bytes per joystick, 1 byte per axis. When Its got a new packet ready, it sends out a signal to the RC. When the RC is ready to receive, it sends a signal back. The RC receives the packet, then sends out its 10 byte, 2 integer packet back.
But I'm having trouble with the inner workings of this routine. I browsed through the pc_interface.c file included in the packet, and found the Wait4TXEmpty function call. I noticed that when I tried to compile the project, I couldn't, because the alias.h was referred to as IFI_aliases.h and the IFI_default.h (i think) was missing something. I'm guessing you updated the default code with that function.
Anyway, I'm guessing that it means wait until the PC has pulled this value.
So, when I load up my program (the one I wrote for the joysticks ) and it starts transmitting data, the RC gets stuck in an infinite loop. Now, my PC recognizes if the RC goes offline, so I know it's seeing it right. I just don't think I'm handling everything correctly. Could you give a C code example (even though I'm using Qbasic ...for now...) of how the data's put together and sent/received. Anyway, I have got the joystick input working aok. I've got one flight stick hooked up, and I can pull all the axis, wheel, and buttons from it. The program I have currently calibrates the joystick at startup, then filers the values every cycle, so they range from 0-254, and the axis are lined up correctly. So far so good. I just need an idea of what to do after that. After 1 PC cycle, the next packet is ready. So, I'm supposed to send a small byte to the RC, right? Or do I pull a value?
That's where most of my confusion sets in.
Oh, and another quick question:
What's the setup of the COM connection?
9600baud, no parity, 7 databits, 1 stopbit ?
That also may be where I'm off. Anyway, thank's for the help.
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Look for Team #1132, RAPTAR Robotics at the VCU Regional this year!
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