motor step

[fox_53]

Unless all

specify that are a beginner to the first arms with picbasic pro

I intezione an engine to move step by step with classical schedina STEP and DIR
and there are successful but when you want to see a given (acceleration) on LCD
the frequency of work decreases paurosamente
Almost as I understood the pic can not 'make girasre the engine and at the same time see a given
and so?
there is' a way around the obstacle?
I thank you for helping me understand you can afford

this and 'what I could do with a 16F877


Code:

DEFINE OSC 20
DEFINE  LCD_DREG        PORTD   ' Define LCD connections
DEFINE  LCD_DBIT        4
DEFINE  LCD_RSREG       PORTD
DEFINE  LCD_RSBIT       2
DEFINE  LCD_EREG        PORTD
DEFINE  LCD_EBIT        3
DEFINE LCD_LINES 4
DEFINE LCD_DATAUS 50
VEL  VAR  WORD    ' Velocita''
VELOCITA VAR WORD       
ACC VAR WORD            ' Accellerazio/decellerazione
ACCELL VAR WORD
servo1  VAR  PORTC.1 ' Uscita step motore 1     

         TRISA = 255     ' Enable first button row
         PORTA = %11111111  
        ADCON1 = 7      ' PORTA and PORTE to digital
        Low servo1      ' Servo output low
Main:
    
 READ 0 ,VEL
 'read 1, VELOCITA
  READ 2, ACC
     READ 3, ACCELL
      LCDOut $fe, $80, "VEL =  ", #VEL 
      'LCDOut $fe, $c0, "VELOCITA =  ", #VELOCITA 
      LCDOut $fe, $94, "ACC =  ", #ACC 
      LCDOut $fe, $D4, "ACCELL =  ", #ACCELL 
     GOTO MAINLOOP
     
 
UNO:
 IF PORTA.0 = 1 THEN
 ACC= ACC+1
 PAUSE 10
 ENDIF
 IF PORTA.1 = 1 THEN
 ACC = ACC-1
 PAUSE 10
        ENDIF
    Lcdout $fe, 1   ' Clear screen
        LCDOut $fe, $94, "ACC =  ", #ACC  
 WRITE 2, ACC
   IF PORTA.2 = 1 THEN GOTO DUE
 GOTO UNO
 
 DUE:
   IF PORTA.0 = 1 THEN
 VEL= VEL+1
 PAUSE 10
 ENDIF
 IF PORTA.1 = 1 THEN
 VEL = VEL-1
 PAUSE 10
 ENDIF
 Lcdout $fe, 1   ' Clear screen
        LCDOut $fe, $80, "VEL =  ", #VEL 
 WRITE 0 , VEL
  
   IF PORTA.3 = 1 THEN 
    GOTO MAINLOOP 
   ENDIF  
   GOTO DUE
    
Mainloop:
      
       TRISB = $fe    
         PORTB = 1       
         
       IF PORTB.1 = 1 Then
       GoSUB MOTOR
     ELSE
     GOSUB MOTOR2
          ENDIF
     
               
       IF PORTA.2 = 1 THEN
    Lcdout $fe, 1   ' Clear screen
        LCDOut $fe, $c0, "ENTRATA SETUP "
        PAUSE 1000
                              
        GOTO UNO
        ELSE 
        GOTO MAINLOOP
        ENDIF
                                                    
    MOTOR:
    IF VELOCITA < VEL THEN
         VELOCITA = VEL
           ENDIF 
           
     servo1 = 1      ' Start servo pulse
        PauseUs VELocita
        servo1 = 0      ' End servo pulse
        PauseUs VELOCITA 
             
          velocita = velocita - 1 
               Lcdout $fe, 1   ' Clear screen
       LCDOut $fe, $c0, "VEL ",#VELOCITA  
           
           RETURN
     GOTO MAINLOOP 
     
  MOTOR2:
  
  
     IF VELOCITA < (VEL*3)  THEN         
     servo1 = 1      ' Start servo pulse
        PauseUs VELocita
        servo1 = 0      ' End servo pulse
        PauseUs VELOCITA 
         ELSE      
         VELOCITA = (VEL * 3)
          LOW SERVO1
           ENDIF 
      velocita = velocita + 1 
             RETURN
     GOTO MAINLOOP 
   
  END

[Acetronics2]

Hi,

It's quite simple: your LCD needs some time to work ...

and you can't go against that need of time ...

GLCD tinkerers just begin to understand that ...


the "simple" solution : one pic reads and writes WHILE another drives ...
one "other" solution : use multiplexed 7 segments LEDS ... ( a 4x 16, 20, or 40 display might be funny ... I admit ! )

Alain

[jderson]

Alain-

I am intrigued by the concept of having a dedicated LCD controller PIC. Then, one would send characters serially from the master PIC to the controller PIC? How much time does it take to send a string of characters, relative to the time waiting on the LCD? Is there a way to measure with a scope to determine when the LCD is done?

I guess I'm trying to determine the "trade-offs" here.

Dave