PPDB: SerialTtransfer of 2 ServoValues from LinuxBox to the Board

nomad

hi
i am working with Extended_FDSerial and Servo32

i want transfer 2 different ServoValues from my linuxBox to the Board via RS232.
values: 11_500, 21_150
1n_nnn = servoPort 0
2n_nnn = servoPort 1

with the linuxBox i can transfer the values
a) as: send :11500:21500:
acknowledge from Board "5"
b) or: repeat
send 11500
send 21500
acknowledge from board "5"

My questions:
is this possible with the Spin-Prog to receive 2 different Values
in one call
or must i do this with 2 calls

please give me some help or hints for this problem.
excuse my bad english
regards nomad

StefanL38

Hello Nomad,

Im not really sure if I understand right what you want to do.
For checking my understanding I write how I understand you

You have a RS232-serial device called "Linuxbox"

You can configure the Linuxbox to send the following string: ":11500:21500:"
all in all 13 characters (the double-points included)

Your questions is:

a) Can I send the string ":11500:21500:" to the propeller ?

b) Can the propeller acknowledge the receiving of such a string by sending the character "5" ?

answer to both questions is YES.

If you can make the Linuxbox send a different delimiter at the end example ":11500:21500#"
you can use the method RxStr from the Extended_FDSerial-object (ExtFDS) to receive that string

Sending single characters and sending complete strings is one main purpose of ExtFDS.

If you use the following mouseclicks: Mainmenu of Propellertool
file - archive - project ...

You can easily create a zipfile with all your code that is needed to compile your project.
We can take a look into your code and make detailed suggestions.

nomad

hi StefanL_38
thanks for your answer

b) yes i can make different delimetesr in the linuxBox as: $11500:21500#
this is no problem.

the problem is in the propeller:

1) propeller receive the string: $11500:21500#
2) now the problem:
how can i assign the string into 2 variables:
as: long variable nickservo = 11_500
long variable turnsservo = 21_500

now the propeller works with this 2 variables.
if ok, propeller send the acknowledge "5"

i hope its now clear.


i attached the spin-source for this project
the linux-source is about 10_000 lines, in C++ and for my linux 64bit with a IntelQuad
t
thanks for help
regards nomad

l

StefanL38

Hello nomad,

please create an archive of your project by using

propeller-tool main-menu file - archive - project ...

to create a ZIP-file that contains ALL files that are nescessary to compile your project.
For you this is two clicks away and makes it comfortable for the people that are helping you
that they are not forced to download objects from the obex or comment them out to make
the project compile

anyway:

can you reconfige your linuxbox to send two SEPERATE strings which both start with the port without the "$" or the ":" ?
or leave out the "$" and change the ":" and the "#" to a carriage-return

so the string looks like that "11500<13>21500<13>"

where <13> means ASCII_code decimal 13 which is the carriage return

the method rxDec uses the carriagereturn as the delimiter

see code of

PUB rxDec : Value | place, ptr, x
{{
   Accepts and returns serial decimal values, such as "1234" as a number.
   String must end in a carriage return (ASCII 13)
   x:= Serial.rxDec     ' accept string of digits for value
}}   
    place := 1                                           
    ptr := 0
    value :=0                                             
    dataIn[noparse][[/noparse]ptr] := RX       
    ptr++                           x---here it checks for carriagereturn
    repeat while (DataIn[noparse][[/noparse]ptr-1] <> 13) and (DataIn[noparse][[/noparse]ptr-1] <> Delimiter)                     

then your construction with using

  myInput := Serial.rxDec       ' receive bigNumbers as ServoCommands

will work this way

  myInput1 := Serial.rxDec       ' receive bigNumbers as ServoCommands
  myInput2 := Serial.rxDec       ' receive bigNumbers as ServoCommands

If you cant change the linuxboxstring this way:
Every string is stored in a bytearray

 bytes MyString[noparse][[/noparse]14]  '13 characters and a zero to terminate the string

Your string has always the SAME structure.
Let's assume you string contains "$11500:21500#"

this means:

MyString[noparse][[/noparse] 0 ] = "$"
MyString[noparse][[/noparse] 1 ] = "1"
MyString[noparse][[/noparse] 2 ] = "1"
MyString[noparse][[/noparse] 3 ] = "5"
MyString[noparse][[/noparse] 4 ] = "0"
MyString[noparse][[/noparse] 5 ] = "0"
MyString[noparse][[/noparse] 6 ] = ":"
MyString[noparse][[/noparse] 7 ] = "2"
MyString[noparse][[/noparse] 8 ] = "1"
MyString[noparse][[/noparse] 9 ] = "5"
MyString[noparse][[/noparse] 10 ] = "0"
MyString[noparse][[/noparse] 11 ] = "0"
MyString[noparse][[/noparse] 12 ] = "#"
MyString[noparse][[/noparse] 13 ] = $00 'to terminate the string

Now you can take each single byte and convert to an integer value and do with it whatever you want.

Example:

  Servoport := (MyString[noparse][[/noparse] 1 ] - "0")
   ServoPulse := 0
   ServoPulse := ServoPulse + (MyString[noparse][[/noparse] 2 ] - "0") * 1000  'substract "0"=48 to calculate decimal value out of ASCII-Code-value
   ServoPulse := ServoPulse + (MyString[noparse][[/noparse] 3 ] - "0") * 100
   ServoPulse := ServoPulse + (MyString[noparse][[/noparse] 4 ] - "0") * 10
   ServoPulse := ServoPulse + (MyString[noparse][[/noparse] 5 ] - "0")

in the obex there is also a string-object for string-manipulation-operations
as extract a substring etc. and then convert the substring "11500" to an integervalue

best regards

Stefan

Post Edited (StefanL38) : 9/29/2009 7:33:33 PM GMT

nomad

hi StefanL38,
OK
thanks a lot
but i think, its simple, when i done my original code on linux and on spin.
your way is slower, i must this done in realTime.
also:
linux send (1) propBox receive (1) send acknoledge
linux send (2) propBox receive (2) send acknowledge
this is faster
but thanks for your help
regards nomad

StefanL38

Aha important information dataprocessing has to be a fast as possible.

Then my suggestion is to increase the baudrate up to 115200 baud this is more than 10 times faster than 9600 baud.
and then you have time for all kinds of processing the data in spin.

At 9600 baud the bottleneck is the baudrate not the dataprocessing

best regards

Stefan

Post Edited (StefanL38) : 9/30/2009 3:59:09 PM GMT

nomad

hi
i know
thanks for your replay
regards nomad