To LUGNET HomepageTo LUGNET News HomepageTo LUGNET Guide Homepage
 Help on Searching
 
Post new message to lugnet.robotics.rcxOpen lugnet.robotics.rcx in your NNTP NewsreaderTo LUGNET News Traffic PageSign In (Members)
 Robotics / RCX / *9430 (-20)
  Swan scheduling bug?
 
I'm starting to use the swan firmware and I'm having a problem with the scheduling. It seems like a task with a long wait does not yield properly to other tasks. Here the NQC code sample: task taska() { WaitMS(150); AddToDatalog(9900); } task main() (...) (19 years ago, 22-Sep-05, to lugnet.robotics.rcx)
 
  pbrick and firmware
 
Palm 130, pbrick, rcx 1.0 Can the palm 130 with pbrick be used to control an rcx that doesn't have firmware downloaded? My suspicion is that it won't work without the firmware. Tammy (19 years ago, 22-Sep-05, to lugnet.robotics.rcx)
 
  Re: time sampling under the rcx standard OS
 
(...) Here's a code byte from my LegWay code. ---- int MotorSpeedArray[32] = {1,3,2,0}; // Speeds // ... later in the program... if (sys_time>CheckTime) // check system timer - is it time to check sensors again? { L1 = ReadSensor(SENSOR_1); L3 = (...) (19 years ago, 21-Sep-05, to lugnet.robotics.rcx.nqc)
 
  Re: time sampling under the rcx standard OS
 
Hi Steve, As I'm quite new to BrickOS and to C programming, I'm sorry I'm not sure I understood what you meant, neither how you do this : (...) - Do you check the sensor at a higher rate, and only send a command to the motor at 1kHz ? - How do you (...) (19 years ago, 21-Sep-05, to lugnet.robotics.rcx.nqc)
 
  position servoing under BrickOS
 
Thanks to your advices, Dick, Matt, and Steve, I've been very happy to solve my time sampling problems, installing BrickOS, which runs the rcx fast enough to get a proper position servoing (using rotation or light sensor, and a PID controller). I (...) (19 years ago, 20-Sep-05, to lugnet.robotics.rcx)
 
  error in using brickOS under Bricx Command Center
 
Dear all, I am new to Lego Mindstorms programming. Recently I installed Bricx Command Center in Windows XP Home following the instructions in (URL) I am able to use NQC and leJOS but not brickOS under Bricx Command Center. (Downloading the brickOS (...) (19 years ago, 17-Sep-05, to lugnet.robotics.rcx.legos)
 
  Re: time sampling under the rcx standard OS
 
(...) Well, in BrickOS, my loops usually execute at > 1kHz, so I usually just set it to check the sensor, and set the motor every 1ms. So it just keeps checking the clock. (...) Yes. There's an option that lets you download an "SREC" type of file. I (...) (19 years ago, 19-Sep-05, to lugnet.robotics.rcx.nqc)
 
  Re: time sampling under the rcx standard OS
 
(...) Sorry, I didn't explain. This program only aims at checking the loop frequency capability of the rcx firmware, implementing a PWM. The rotation sensor is only used as a potentiometer knob, allowing me to determine by hand the PWM pulse as (...) (19 years ago, 19-Sep-05, to lugnet.robotics.rcx.nqc)
 
  Re: time sampling under the rcx standard OS
 
Thank you Matt, the RCX loops much faster with your advices : about 10 loops per second. But as this frequency depends on the calculations included in the loop, I’m afraid this will not be enough. So I tried to download (URL) but it just appears as (...) (19 years ago, 18-Sep-05, to lugnet.robotics.rcx.nqc)
 
  Re: time sampling under the rcx standard OS
 
Thank you Dick, for advicing me to switch to the faster firmware, I’m sure I need both a 1-millisecond basic clock, and the 128 power level capability. So I tried to download it from (URL) but it just appears as a text file, which I don’t know how (...) (19 years ago, 18-Sep-05, to lugnet.robotics.rcx.nqc)
 
  RE: time sampling under the rcx standard OS
 
Here are some comments on how to improve your code for real-time performance. 1. Move the "SetUserDisplay" out of the loop and put it just before the loop. 2. I think the "OnFwd" macro is actually two instructions: "Fwd" and then "On". Replace this (...) (19 years ago, 17-Sep-05, to lugnet.robotics.rcx.nqc)
 
  Re: time sampling under the rcx standard OS
 
(...) From what I've seen, the standard firmware takes about 3ms per command, and the same program will run on BrickOS about 100 times faster. I usually set up my BrickOS programs so they use the internal timer, and only update the motor setting (...) (19 years ago, 17-Sep-05, to lugnet.robotics.rcx.nqc)
 
  Re: time sampling under the rcx standard OS
 
(...) Francois, I think you should be able to get much faster sampling. I can easily get 10-20 Hz, and others have claimed to get down to 3 ms. Whether it can be done at a constant rate, I'm not sure, and think it probably depends on what else is in (...) (19 years ago, 17-Sep-05, to lugnet.robotics.rcx.nqc)
 
  time sampling under the rcx standard OS
 
Hi list, I'm trying to implement a position regulation (using a motor and a rotation sensor), using for instance a PID (Proportional-Integr...erivative) regulation. I tried to code it in NQC, using the standard OS, but it seems that the RCX loops at (...) (19 years ago, 17-Sep-05, to lugnet.robotics.rcx.nqc)
 
  time control : BrickOS versus the RCX standard OS ?
 
Hi list, I'm trying to implement a position regulation (using a motor and a rotation sensor), using for instance a PID (Proportional-Integr...erivative) regulation. I tried to code it in NQC, using the standard OS, but it seems that the RCX standard (...) (19 years ago, 17-Sep-05, to lugnet.robotics.rcx.legos)
 
  IR-based proximity measurement
 
I'm changing the subject line in the middle of the thread. Wonder what the server will do with that... I tried out Brian's "Max-picking" ping method, as well as a few other things. Here's a summary of what I found: 1) If the active sensor readings (...) (19 years ago, 16-Sep-05, to lugnet.robotics.rcx.nqc)
 
  Re: direct manipulation of bits in RCX registers using NQC
 
(...) Correct. A NQC command (say, "Wait(10);") is converted to one or more "bytecodes" (in this case, one bytecode, namely a string of 4 bytes (0x43 0x02 0x0a 0x00), the first of which is a command (0x43) while the following three are information (...) (19 years ago, 16-Sep-05, to lugnet.robotics.rcx.nqc)
 
  Re: direct manipulation of bits in RCX registers using NQC
 
Hey, Thanks for all the helpful responses, everyone. Brian: (...) I guess that "firmware" must be the code that tells RCX how to interpret user instructions (NQC, C, IC, opcodes, or whatever), and convert them to binary machine-specific code. Right? (...) (19 years ago, 16-Sep-05, to lugnet.robotics.rcx.nqc)
 
  Re: RCX to RCX NQC
 
(...) And that explains why I was having so much trouble with my custom Tcl based uploader in high speed mode. I fixed it a while ago by adding a slight bit of extra time between messages, but never got to the root of the problem. Thanks Dick! (...) (19 years ago, 15-Sep-05, to lugnet.robotics.rcx)
 
  RCX to RCX NQC
 
One last email on this topic. There's new opcodes in the Swan firmware to support many data bytes in a single "mailbox" message. The standard firmware supports "mailbox" messages with a single byte parm. I found this very restrictive in building RCX (...) (19 years ago, 15-Sep-05, to lugnet.robotics.rcx)


Next Page:  5 more | 10 more | 20 more

Redisplay Messages:  All | Compact

©2005 LUGNET. All rights reserved. - hosted by steinbruch.info GbR