Stupid Question <FullDuplexSerial>

grasshopper · 2008-09-15 20:54

This is a stupid question but i cant seem to figure it out


Main
  StartBit := "0"  
  SorC := "-"  
  Sor3 := "+"

ser.str(string(startbit))

It wont send the data "0" out the serial port. I guess i need to send various conditions of my program i.e startbit and Sorc etc...

Help is appreciated

Paul Baker · 2008-09-15 22:36

The reason it doesn't work is that string() requires an inline string constant, meaning the string literally has to be inside the parenthesis.

Without knowing more background on what you are trying to do, it's hard to point you in the right direction. The answer may be as simple as ser.tx(StartBit).

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Paul Baker
Propeller Applications Engineer

Parallax, Inc.

Post Edited (Paul Baker (Parallax)) : 9/15/2008 11:51:44 PM GMT

Mike Green · 2008-09-15 22:43

If a variable X is a WORD or LONG, you can do X := "0" then you can do ser.str(@X) and it will transmit the character "0". This works because the character "0" is stored in the lowest address of the WORD or LONG and the next byte will be a zero. If X is a LONG, you can even do X := "0" + ("1" << 8) or X := "A" + ("B" << 8) + ("C" << 16) and this will display as "01" or "ABC".

grasshopper · 2008-09-16 05:37

Sorry Paul for not being more specific.

I will have my variables as a byte. I not only want to use the "+" and "-" but also a "0" and"1". these variables will be toggled in my program and then "glued" together in one long string for a user to note the current condition of the device I am designing.

i.e a returned string would look something like this on the computer side

[noparse][[/noparse]Condition = 1--0]

The pseudo propeller code would look like this


Var
  byte StartBit, SorC ,SorC, SorE

OBJ 
  ser  = "Fullduplexserial"

Pub Main

  SorB := "0"  
  SorC := "-"  
  SorD := "+"
  SorE := "+"

Pub Running

  ser.str(String("[noparse][[/noparse]Condition = "))
  ser.str(SorB)
  ser.str(SorC)
  ser.str(SorD)
  ser.str(SorE) 
  ser.str)string("]")

Mike I will try some thing like you demonstrated.

grasshopper · 2008-09-16 05:45

Mike Green said...
If a variable X is a WORD or LONG, you can do X := "0" then you can do ser.str(@X) and it will transmit the character "0". This works because the character "0" is stored in the lowest address of the WORD or LONG and the next byte will be a zero. If X is a LONG, you can even do X := "0" + ("1" << 8) or X := "A" + ("B" << 8) + ("C" << 16) and this will display as "01" or "ABC".

After reading this over and over I ask you this...

A character is how many bits? I am imagining 8 bits, not sure but 1111 = 15 so this is directly related to hex or F or 1/2 a byte since "A" = $41

A Long can hold how many characters? perhaps 32 bit? thus = 1111 1111 1111 1111 1111 1111 1111 1111 or 4 characters?

and while i am asking may as well ask what the hell a <<8 is doing? Bit shifting left? Why left? Why not right?

Thanks for any help ...

Mike Green · 2008-09-16 05:51

You can just use the single character output routines: ser.tx(SorB)
What you wrote will also work if you change everything to WORDs (with VAR WORD SorB, SorC, SorD, SorE)
and put "@" in front of the variable names like: ser.str(@SorB)
Again, this is because a single character stored in a WORD looks the same as a byte with the character
followed by a zero byte (which makes it a string to Spin).

StefanL38 · 2008-09-16 08:25

hello grasshopper,

as you send single bytes i would prefer the command for sending a single byte

so your code posted above would be changed to

Var
  byte StartBit, SorC ,SorC, SorE

OBJ 
  ser  = "Fullduplexserial"

Pub Main

  SorB := "0"  
  SorC := "-"  
  SorD := "+"
  SorE := "+"

Pub Running

  ser.str(String("[noparse][[/noparse]Condition = "))
  ser.tx(SorB)
  ser.tx(SorC)
  ser.tx(SorD)
  ser.tx(SorE) 
  ser.str(string("]"))

best regards

Stefan

grasshopper · 2008-09-16 15:01

StefanL38 said...
hello grasshopper,

as you send single bytes i would prefer the command for sending a single byte

so your code posted above would be changed to
Var
  byte StartBit, SorC ,SorC, SorE

OBJ 
  ser  = "Fullduplexserial"

Pub Main

  SorB := "0"  
  SorC := "-"  
  SorD := "+"
  SorE := "+"

Pub Running

  ser.str(String("[noparse][[/noparse]Condition = "))
  ser.tx(SorB)
  ser.tx(SorC)
  ser.tx(SorD)
  ser.tx(SorE) 
  ser.str(string("]"))
best regards

Stefan

This does not work... Hum

I even tried making the variables a long as well

Mike Green · 2008-09-16 15:31

Saying "This does not work" is not very useful. You're more likely to get useful information if you describe what happened.

That said, why do you have "Pub Running"? That creates a separate method (subroutine) which is never called.
Try putting "Running" after the 'SorE := "+"' line or simply removing the "Pub Running".

grasshopper · 2008-09-16 15:45

Sorry Mike your right I was quick to complain without a clear discription

Here is the code that works but not efficient.

Var
   long SorB, SorC, SorD, SorE

Pub Main

  SorB := "0"  
  SorC := "-"  
  SorD := "+"
  SorE := "+"

Pub Running 

      ser.str(String("[noparse][[/noparse]Condition = "))
                                                              
     IF (SorB == "0")
           ser.str(string("0")) 
     IF (SorB == "1")
           ser.str(string("1"))
                                
     IF (SorC == "-")
           ser.str(string("-")) 
     IF (SorC == "+")
           ser.str(string("+"))
                                                                                                                                          
     IF (SorD == "+")
           ser.str(string("+")) 
     IF (SorD =="-")
           ser.str(string("-"))
                                                         
     IF (SorE == "C")
           ser.str(string("C")) 
     IF (SorE == "S")
           ser.str(string("S"))
 
  ser.str(string("[noparse][[/noparse]Condition = "))

I have tried all of the examples listed but no luck, The one i posted works but it is not a great way to go about it. The variables will change during run time

Mike Green · 2008-09-16 15:49

What you've posted can't possibly work (because of the "Pub Running").

How about posting what you really used? Try attaching the file to your message so there's no possibility of the forum software "eating" some of it.

StefanL38 · 2008-09-16 18:13

hello grashopper,

the following code IS running on my propeller

So if it does not run on yours it's NOT a coding-problem
Then the problem must be somewhere else


'Use F11 to store program into the EEPROM.
'If you open the COM-Port with a terminalsoftware this may cause
'a reset of the propellerchip and then
'the content of RAM will be overwritten by the content of the EEPROM

CON
  _clkmode = xtal1 + pll16x
  _xinfreq = 5_000_000

Var
  byte StartBit, SorB, SorC ,SorD, SorE


OBJ
  'give the serialdriver object wich is defined in the file "FullDuplexSerial.SPIN"
  'the name "Ser" 

  Ser : "FullDuplexSerial"  


Pub Main

  SorB := "0"  
  SorC := "-"  
  SorD := "+"
  SorE := "+"

  Ser.start(31, 30, 0, 9600)                    ' start serialdriver in a new cog with parameters Rx-Pin is Pin 31 Tx-Pin is Pin 30, mode 0, 9600 baud
  
  repeat 
    Running
    WaitCnt(clkfreq + cnt)

Pub Running

  ser.str(String("[noparse][[/noparse]Condition = "))
  ser.tx(SorB)
  ser.tx(SorC)
  ser.tx(SorD)
  ser.tx(SorE) 
  ser.str(string("]"))
  ser.tx(13)

best regards

Stefan

Stupid Question <FullDuplexSerial>

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