You can make your own and just buy some of the parts from them.  Then you will
save some money and learn from the experence.  If you would like some ideas
email me and I could send you a picture of my version.


Eric Engler <englere.geo@...> wrote:
           I've got wall-to-wall shag carpet in my living room. Can the
Robodyssey work on this, or does it prefer a flat surface?

Some 2 wheel robots (2 main wheels, sometimes with a small third
wheel) get hung up on shag carpet and I'd hate to spend $250 without
knowing how well this might work.

Eric






---------------------------------
Don't get soaked.  Take a quick peak at the forecast
  with theYahoo! Search weather shortcut.

[Non-text portions of this message have been removed]

> ... I need the exponent of a loop counter, but I get a "float
mantissa" error when I do so.

What is an exponent of a loop counter?  What code produces this error?


Tom

I have a working BasicX-24 system which takes keyboard on/off
messages and creates MIDI messages to an electronic keyboard. This
has worked fine for over a year.

I am creating a 2nd system to convert MIDI messages on the fly for a
friend who has a non-MIDI Standard system.

On booting the BasicX-24 I successfully generate a bunch of test note
on then note off messages.

Code below:
==================================
Dim ScanClockCount As Byte
Call ClearQueue(InComm)
Call ClearQueue(OutComm)
   For ScanClockCount = 35 To 55
     Delay (0.1)
     OutputData(1) = 144
       OutputData(2) = ScanClockCount
       OutputData(3) = 64
       Call PutQueue(OutComm, OutputData, 3) 'send all data for this
note
     Delay (0.1)
       OutputData(1) = 144
       OutputData(2) = ScanClockCount
       OutputData(3) = 0
       Call PutQueue(OutComm, OutputData, 3) 'send all data for this
note
     Next

=============================

Again, the code above works fine. I cannot seem to get the parsing
code to work so I simply tried to take whatever came in and send it
right back out. This does not work either. At most maybe a single
note will play and never turn off.

It is almost like when I do the "GetQueue" for the current byte count
I may be disturbing any bytes which may still be coming in. I did not
think that would happen.

Note: I have verified that I am safe with RAM usage and the code is
minimal. (much less than the working system)

  InComm and OutComm are dimensioned (1 to 59) and InputData is (1 to
45). I am only sending single notes (3 bytes each) so I am no where
near buffer overflow.

See code below:
======================================
Do
Count = GetQueueCount(InComm) 'look for number of bytes in input
queue.
       If Count > 0 Then 'data in input buffer ready to process
         Call GetQueue(InComm, InputData, Count) 'transfer data from
input queue to array
         For Lc = 1 To Count
           OutputData(Lc) = InputData(Lc)
         Next
          Call PutQueue(OutComm, OutputData, CInt(Count))
        End If
Loop
===========================================
Any help would be appreciated.
Thanks,
Craig

> ... InComm and OutComm are dimensioned (1 to 59) and InputData is (1
to 45). I am only sending single notes (3 bytes each) ...

I don't know much about MIDI on the BX-24 beyond the rate issue, but I
have an unrelated suggestion.  If you don't need to have large buffers,
save the RAM space to eliminate the possibility - perhaps likelihood -
that you've crashed the stack.

For testing, if you only need to send three bytes, try three-byte
stacks, or maybe six, but there's no need to allocate 59 bytes in early
code testing.

Another simple technique is to insert a line here or there that simply
turns on, or toggles, one of the processor LEDs to determine where the
code is failing or looping.


Tom

Should read:

For testing, if you only need to send three bytes, try three-byte
_queues_, or maybe six...


Tom

Hello
I need to multiplex one of the ADC pins of BasicX in order to receive
signals from 4 analog devices...(Of course using 2 digital pins for
address purposes)
Can anyone suggest a mux to use in such application?
Cheers

David

I have 3 sources/destinations using serial I/O

So I have defined 3 different I/O queues.

Is there anything I have to do when switching the com3 port to a
different queue? Do I have to wait and make sure the queues are empty?

What haves when data comes in into a certain active input queue and I
do a OpenCom to a different Queue and a re-DefineCom?

Wim

> Can anyone suggest a mux to use in such application?

74HC4066?  CD4066?


Tom

Hi,

  Check LTC 1390 from Linear technology If your are not limited by I/O pins. This
mux is driven by 3 lines and is control serially by software control.


  rosarite

  -----Original Message-----
  From: davidsousamendes@...
  To: basicx@yahoogroups.com
  Sent: Mon, 5 Mar 2007 5:07 AM
  Subject: [BasicX] MUX

      Hello
  I need to multiplex one of the ADC pins of BasicX in order to receive
  signals from 4 analog devices...(Of course using 2 digital pins for
  address purposes)
  Can anyone suggest a mux to use in such application?
  Cheers

  David


________________________________________________________________________
AOL now offers free email to everyone.  Find out more about what's free from AOL
at AOL.com.


[Non-text portions of this message have been removed]

--- In basicx@yahoogroups.com, "davidsousamendes"
<davidsousamendes@...> wrote:
>
> Hello
> I need to multiplex one of the ADC pins of BasicX in order to receive
> signals from 4 analog devices...(Of course using 2 digital pins for
> address purposes)
> Can anyone suggest a mux to use in such application?
> Cheers
>
> David
>
You can also use an outboard A/D converter, like the Microchip
MCP3204.  This has an SPI interface so it uses only one of the general
IO pins on the BX plus the 3 hardware SPI pins.

Data sheet:
http://ww1.microchip.com/downloads/en/DeviceDoc/21298c.pdf

I just finished testing its 8-chan brother, I am putting an example
program in the Files area.

I don't know much about your application, but on my robot I will be
using a few 4052's.

Gary T

>Hello
>I need to multiplex one of the ADC pins of BasicX in order to receive
>signals from 4 analog devices...(Of course using 2 digital pins for
>address purposes)
>Can anyone suggest a mux to use in such application?
>Cheers
>
>David
>
>

I am considering using a BX-35 for a project and I have a few questions.

First, from posts in this newgroups, it looks like to use more than 2
UART's you simply share COM3 between the second and subsequent UART's
calling DEFINE COM3 and OPEN COM each time you want to switch between
them.  Does this significantly slow down the processor?  Do you know
how big a performance hit this incurs?  If this does make for
performance issues, are there any alternatives to this?

Second, I have read some posts about overclocking the BX-35 to get its
performance up to the BX-24p's level.  The post I read said that 10Mhz
works fairly reliably.  Do you have any experience with this?  Is there
a particular crystal that you would recommend?  Would the values of the
22pF capacitors need to be changed when using a different crystal?

Third, I saw another post that talked about using a 64K EEPROM for
extra code space with the BX-35.  Do you have a specific 64K EEPROM
that you would recommend for this?  The post talked about letting the
BASICX IDE know about using the 64K EEPROM.  Is the entire 64K
available for use by BASICX code?

Is there any 'unofficial' documentation that covers any of these topics?

I would greatly appreciate any help you can give on these questions.

Thanks,
Rich

Hello,

I'm working on a project to connect the BasicX-24 to an eb505
Bluetooth transceiver from A7 Engineering. I am trying to issue
a "connect to the MAC address of another Bluetooth device" command to
the eb505 from the bx-24 and have been unsuccessful. I've tried
sending strings and individual ASCII characters followed by a
carriage return with no success.

The device I am trying to connect to is an eb500 connected via a
serial cable to a PC running Hyper Terminal. If I issue the command
to connect the 500 to the 505, a connection is established; however,
issuing the same command (with the other devices MAC address) from
the bx-24 to the 505, a connection is not established.

I've verified that the bx-24 is outputting the correct command by
connecting the output to Hyper Terminal and reading the result. Has
anyone had a similar experience with this? What could I being doing
wrong? I've attached my code incase the error is in it. I'd
appreciate any help that can be offered.

Dim Com1In(1 to 40) As Byte
Dim Com1Out(1 to 40) As Byte

Sub Main()

'OpenQueue(Queue, Size)
Call OpenQueue(Com1In, 40)
Call OpenQueue(Com1Out, 40)

'OpenCom(PortNumber, BaudRate, InputQueue, OutputQueue)
Call OpenCom(1, 9600, Com1In, Com1Out)

Call ConnectCommand

End Sub

Sub ConnectCommand()

'Wait 2 sec for eb505 to initialize
Call Sleep(2000)

'Send CON 00:0C:84:00:1A:B9 to the output queue
Call PutQueueStr(Com1Out,Chr(67) & Chr(79) & Chr(78) & Chr(32) &
Chr(48) & Chr(48) & Chr(58) & Chr(48) _
& Chr(67) & Chr(58) & Chr(56) & Chr(52) & Chr(58) & Chr(48) & Chr(48)
& Chr(58) & Chr(49) & Chr(65) _
& Chr(58) & Chr(66) & Chr(57) & Chr(13))

Call Sleep(500)

End Sub

> ... issuing the same command [] from the bx-24 to the 505, a connection is not
established.

Try reversing RX and TX when connecting the BX-24 to the radio.


Tom

Rich,

One thing that has been mentioned with respect to changing the clock
frequency is that the serial baud rates will change as well.  Unless
you can set the counters or establish a relationship with the clock
frequency that shifts one baud rate up to another (say 14400 for 9600)
there will be problems with serial I/O.

Other timer-based commands will change as well.

If the standard clock frequency doesn't do it for this otherwise very
capable chip, there are other products that run faster.

Good luck,

Dennis


--- In basicx@yahoogroups.com, "Rich Mays" <rich_mays@...> wrote:
.....

> Second, I have read some posts about overclocking the BX-35 to get its
> performance up to the BX-24p's level.  The post I read said that 10Mhz
> works fairly reliably.  Do you have any experience with this?  Is there
> a particular crystal that you would recommend?  Would the values of the
> 22pF capacitors need to be changed when using a different crystal?
>

--- In basicx@yahoogroups.com, "tombhandley" <gr13tbs@...> wrote:
>
> I've posted a Parallax/Hitachi HM55B Compass module with a test
> example, calibration routine, and instructions on my web site at
> [HM55B.zip]:
>
> http://home.comcast.net/~tomhandley/bx-24/bx-24.html
>
> - Tom
>

Anyone got this saved? We are working on trying to calibrate our compass
(HM55B), but no luck so far...

Google HM55B.zip

Is this it?

http://pruim037.proboards107.com/index.cgi?board=technicalmb&action=display&thre\
ad=1104250898&page=13


Tom

--- In basicx@yahoogroups.com, Tom Becker <gtbecker@...> wrote:
>
> Google HM55B.zip
>
> Is this it?
>
> http://pruim037.proboards107.com/index.cgi?
board=technicalmb&action=display&thread=1104250898&page=13
>
>
> Tom
>

googled it, got 2 replys, one 404 and the other one you posted,
thatone referrs to http://home.comcast.net/~tomhandley/bx-24/bx-
24.html wich is down.

the code is posted on that page, but I want the calibtarion program
and maybe some guidelines howto calibrate it.


Anders

> ... I want the calibration program and maybe some guidelines how to
calibrate it.

Tom Handley vanished in late 2005 and his work seems to have vaporized, too.

The Hitachi HB55B is similar to other two-axis magnetometers applied to
compassing, so the calibration techniques of other sensors will guide
you well.  I'm currently working with Honeywell parts and have found
their application notes very helpful.  At http://www.magneticsensors.com
(a Honeywell site), find AN214, for example, which suggests the general
method of rotating the _level_ compass while sampling to find the
maximum and minimum of X and Y, which are then plugged into a simple
compassing algorithm.  Other methods achieve similar results by
interpolating between X/Y magnitude pairs taken and stored in a table
while rotating at a constant rate.

These methods assume that the sensor is level.  You will find that tilt
will introduce large errors so, if you are building a hill-climbing
robot, for example, you must also incorporate tilt sensors to correct
the compass outputs.


Tom

Is it possible to use a mechanical gimbal<http://en.wikipedia.org/wiki/Gimbal>
to keep the compass level?

On 3/7/07, Tom Becker <gtbecker@...> wrote:
>
>    > ... I want the calibration program and maybe some guidelines how to
> calibrate it.
>
> Tom Handley vanished in late 2005 and his work seems to have vaporized,
> too.
>
> The Hitachi HB55B is similar to other two-axis magnetometers applied to
> compassing, so the calibration techniques of other sensors will guide
> you well. I'm currently working with Honeywell parts and have found
> their application notes very helpful. At http://www.magneticsensors.com
> (a Honeywell site), find AN214, for example, which suggests the general
> method of rotating the _level_ compass while sampling to find the
> maximum and minimum of X and Y, which are then plugged into a simple
> compassing algorithm. Other methods achieve similar results by
> interpolating between X/Y magnitude pairs taken and stored in a table
> while rotating at a constant rate.
>
> These methods assume that the sensor is level. You will find that tilt
> will introduce large errors so, if you are building a hill-climbing
> robot, for example, you must also incorporate tilt sensors to correct
> the compass outputs.
>
> Tom
>
>
>



--
Scott
http://robotbuilding.blogspot.com/

Minds are like parachutes, they only function when they are open.


[Non-text portions of this message have been removed]

I tried our suggestion, however I was pretty sure I hooked them up
properly before, and the result did not change. I'm going to connect a
new 505 chip and see if that is the problem.



--- In basicx@yahoogroups.com, Tom Becker <gtbecker@...> wrote:
>
> > ... issuing the same command [] from the bx-24 to the 505, a
connection is not established.
>
> Try reversing RX and TX when connecting the BX-24 to the radio.
>
>
> Tom
>

I guess I answered my own question by reading the info on the honeywell
website.  I had no idea there was so much stuff out there for compassing.

I am currently working on creating a GPS/compass navigating rover.  Does
anyone have any good suggestions on how to get started?  I am looking for
suggestions on chips and stuff.  For example, I was just looking at the
hrm3200, which looks great.

I am planning on using a ZX-24a and the main microcontroller for navigation,
servos, etc....  I also have a BS2, which may be used for some sensors and
stuff.

If you have not already guessed, I am a newbie to this stuff.

On 3/7/07, Scott <hacktorious@...> wrote:
>
> Is it possible to use a mechanical gimbal<http://en.wikipedia.org/wiki/Gimbal>
> to keep the compass level?


[Non-text portions of this message have been removed]

Hi everyone. I am currently developing a distributed wireless acquisition
system based upon a Basicx BX-24P. Each acquistion point has essentially one
BX-24P, one AD7710 24 bit A/D converter and one MaxStream XBee radiomodem
module. There are several acquistion points, each of which sends its sampled
data to a laptop computer for data logging and real-time visualization.
Unfortunately, it seems to me that the available amount of RAM for the
BX-24P is quite small for such an application, which is strange because if
this processor can run a quite sophisticated robot I do not understand why
it cannot handle a relatively simple acquisition node. Each BX-24P runs the
main program, a task to handle interrupts and a task to blink a led with
different modes to show the user what state the acquisition point is
currently in (initialization, calibration, acquisition, transmission, ecc
...). The whole program is about 8000 lines of code. Have you ever
experienced RAM limitation problems in your applications ? How did you solve
the riddle ? How can I compute the exact amout of RAM memory used by my
application in order to check if the problem is really related to RAM
limitation ?

Thanks,

Fabrizio

_________________________________________________________________
Ogni ricerca da questo sito, una donazione per i bambini rifugiati
http://click4thecause.live.com/Search/Charity/Default.aspx?locale=it-it

> ... Is it possible to use a mechanical gimbal  ...?

Yes, with difficulty, IMO. You can also steer a level compass module
with a servo, though, itself controlled by a tilt sensor.  Here's an
approach I tried:
http://tech.ph.groups.yahoo.com/group/basicx/photos/browse/a646

This is a Honeywell HMC6352 on a Sparkfun breakout board, mounted to a
brass tube that is held in teflon-plumbing tape in nylon clamps, steered
by a hobby servo via a pair of identical cranks and a carbon-fiber
control rod.  The servo is driven by a BX-24 that takes signals from an
ADXL203 accelerometer and an ADXRS401 rate gyro, combined in a
pseudo-Kalman filter, implemented in code.  Compass data comes off the
breadboard via the Bluetooth radio near the batteries, whose steel
shells, along with the servo motor magnets, are as far from the compass
as possible, hence the control rod.

For single-axis levelling, this works very well.  For two-axes, it
becomes more complicated.


Tom

--- In basicx@yahoogroups.com, Tom Becker <gtbecker@...> wrote:
>
>  > ... I want the calibration program and maybe some guidelines
how to
> calibrate it.
>
> Tom Handley vanished in late 2005 and his work seems to have
vaporized, too.
>
> The Hitachi HB55B is similar to other two-axis magnetometers
applied to
> compassing, so the calibration techniques of other sensors will
guide
> you well.  I'm currently working with Honeywell parts and have
found
> their application notes very helpful.  At
http://www.magneticsensors.com
> (a Honeywell site), find AN214, for example, which suggests the
general
> method of rotating the _level_ compass while sampling to find the
> maximum and minimum of X and Y, which are then plugged into a
simple
> compassing algorithm.  Other methods achieve similar results by
> interpolating between X/Y magnitude pairs taken and stored in a
table
> while rotating at a constant rate.
>
> These methods assume that the sensor is level.  You will find that
tilt
> will introduce large errors so, if you are building a hill-
climbing
> robot, for example, you must also incorporate tilt sensors to
correct
> the compass outputs.
>
>
> Tom
>


Okay, looked at that datasheet and tried that calibration
approach...but not very succesful...maybe the environment is just to
noisy...

when I turn 90 degrees i eithert get around 70 or 120 on the
compass...but always 360(+- a few) when turning a full circle...

sounded like calibration to be, but I dont know...

anyway, I'll try another module tomorrow...with greater accuracy

here are a few photos of the robot btw.
Autonomus, rescue inpired (send into (burning) building, locate
objects, return with map of building).

http://193.11.222.247:8080/skolarbeten/mekatronik/docu/RobotBygge0702
29%20007.JPG
http://193.11.222.247:8080/skolarbeten/mekatronik/docu/RobotBygge0702
29%20004.JPG

neither compass or, IR or ultrasound is mounted on those pics...
(compass placed ~20cm above chassis)

Anders

> ... neither compass or, IR or ultrasound is mounted on those pics...

The top photo looks like a Parallax HM55B is in the BOE breadboard.
With a drive motor or two only 10cm or 20cm from it, you will not see
good compass results.

It is not noise that is affecting your results, I suspect, just a heavy
local magnetic bias from the motor magnets, and, perhaps, a varying
magnetic field from the motor coils as they rotate in two directions,
driven by a varying current.

A more accurate compass will not improve that.  Mµ-metal shielding and
distance will; magnetic fields decrease according to the inverse of the
squared distance.  If you look around online at other small compassed
robot vehicles, you'll often see the compass sitting atop a mast of some
considerable height to reduce the bias that the vehicle produces.

Welcome to compassing.


Tom

--- In basicx@yahoogroups.com, Tom Becker <gtbecker@...> wrote:
>
> > ... neither compass or, IR or ultrasound is mounted on those
pics...
>
> The top photo looks like a Parallax HM55B is in the BOE
breadboard.
> With a drive motor or two only 10cm or 20cm from it, you will not
see
> good compass results.
>
> It is not noise that is affecting your results, I suspect, just a
heavy
> local magnetic bias from the motor magnets, and, perhaps, a
varying
> magnetic field from the motor coils as they rotate in two
directions,
> driven by a varying current.
>
> A more accurate compass will not improve that.  Mµ-metal shielding
and
> distance will; magnetic fields decrease according to the inverse
of the
> squared distance.  If you look around online at other small
compassed
> robot vehicles, you'll often see the compass sitting atop a mast
of some
> considerable height to reduce the bias that the vehicle produces.
>
> Welcome to compassing.
>
>
> Tom
>

probably only there for testing at that moment, or I put it there so
I would not loose it...=)

It's located 20cm above the 3mm alu plate, on the opposite side of
the motors...

and I always have eveything turned off while measuring...

> It's located 20cm above the 3mm alu plate, on the opposite side of
the motors... and I always have everything turned off while measuring...

The aluminum won't offer much protection.  The motors are just too
close, I think you'll find.


Tom

The basic algorithm is as follows:

  for t = 1 to 16
number = 2^t
next

  I can post the actual code at some point soon, but the basic
relevant info is above.



--- In basicx@yahoogroups.com, "Tom Becker" <gtbecker@...> wrote:
>
> > ... I need the exponent of a loop counter, but I get a "float
> mantissa" error when I do so.
>
> What is an exponent of a loop counter?  What code produces this
error?
>
>
> Tom
>

> for t = 1 to 16
> number = 2^t
> next

Oh!  The loop count as an exponent!  All parameters must be floats.

Try:

sub Main()
   dim t as byte, number as single
   for t = 1 to 16
    number = 2.0 ^ csng(t)
    debug.print cstr(t) &": "& cstr(number)
    next
end sub


Tom