PBP projects for R/C models

**rmteo** · - 27th January 2010, 22:50

Ken,

Can you do a LED blinky without using PAUSE (or any other delay commands)? Try to do a 1 second blinky using a timer. When you can do that, you will be well on your way to solving your motor ESC problem.

**Kenjones1935** · - 28th January 2010, 04:45

Guys and maybe Gals,

I am getting frustrated. I can not find the documentation that I need. I need Assembler Language details for the 16-bit chips. I need 16-bit BASIC libraries (Microchip talks C, not Basic). Darrel Taylor is rebuilding his site. He is not accepting new members.

Microchip has screwed up on this link:

MPLAB Assembler, Linker and Utilities for 16-Bit Devices User's Guide
which points to-->
http://ww1.microchip.com/downloads/e...Doc/51317G.pdf

But when you download51317G you discover it is about the 24-BIt devices. It is the same document that -->

DS51317 - MPLAB Assembler, Linker and Utilities for PIC24 MCUs and dsPIC DSCs User's Guide

points to.

What is the number for the 16-Bit devices user's guide?? I have not found a complete list of Assembly language code, syntax, structure whatever! Without that I do not see how I can understand what this 16F887 is doing.

Also it is late. I am going to bed.

Ken

**mackrackit** · - 28th January 2010, 05:02

Ken,

Darrel's site must have been down for what evere reason. It seems to work now.
http://www.PBPgroup.com/

ASM instuctions are normally in the devices data sheet. But... Please do not take this the wrong way. If you are having trouble with Basic I doubt it ASM will do much good.

I like remto's sugesstion about blinky. Give that a shot.

**rmteo** · - 28th January 2010, 19:34

Originally Posted by mackrackit

Ken,

....ASM instuctions are normally in the devices data sheet. But... Please do not take this the wrong way. If you are having trouble with Basic I doubt it ASM will do much good.

I like remto's sugesstion about blinky. Give that a shot.

Ken, I highly recommend taking Dave's advise. You need a better understanding of what makes a PIC tick (hint, read the free book I linked to). When you have that under your belt, then the coding is the really easy part. It doesn't matter whether you use C, BASIC (PBP or some other variant) or ASM - the situation is the same.

**ScaleRobotics** · - 29th January 2010, 10:40

Here is some code that will measure an RC receiver pulse width coming in on GPIO.2, perform a little math on the value, and put out the wave form out on GPIO.1, using DT Interrupts.

It's on a little 12F683 and was written for 8mhz internal. Looks pretty good on the scope. I need to test it on a motor controller though. But time for bed.....

Code:

<html>
<head></head>
<body><!--StartFragment--><pre><code><font color="#000080"><i>
</i></font><b>DEFINE </b>OSC 8
<b>INCLUDE </b><font color="#FF0000">&quot;DT_INTS-14.bas&quot;</font><font color="#000080"><i>;interrupt routines
</i></font><b>INCLUDE </b><font color="#FF0000">&quot;sub16.inc&quot;     </font><font color="#000080"><i>; subtract 16 bit macro

</i></font><b>DEFINE </b>DEBUG_REG	GPIO
<b>DEFINE </b>DEBUG_BIT	0
<b>DEFINE </b>DEBUGIN_BIT	1

<b>DEFINE </b>DEBUG_BAUD	38400
<b>DEFINE </b>DEBUG_MODE	0

INTCON = %10101000      <font color="#000080"><i>'
</i></font>OSCCON = %01110000      <font color="#000080"><i>'set for 8mhz internal
</i></font>CMCON0 = 7              <font color="#000080"><i>'TURN COMPARITORS OFF
</i></font>ANSEL  = %00000000      <font color="#000080"><i>'Set A/D OFF
</i></font>ADCON0 = %00000000      <font color="#000080"><i>'Analog converter OFF 
</i></font>TRISIO = %010100        <font color="#000080"><i>'Set GSIO 4 and 2 to INPUT, others to OUTPUT
</i></font>OPTION_REG = %11000010
T1CON  = %00110001
T2CON  = %01001110
CCP1CON = %00000101

risetime <b>VAR WORD       </b><font color="#000080"><i>;used for pulse width measure start of pw

</i></font>falltime <b>VAR WORD       </b><font color="#000080"><i>;time at end of pulse width
</i></font>falltime_l <b>VAR </b>falltime.Byte0
falltime_h <b>VAR </b>falltime.Byte1
risetime_l <b>VAR </b>risetime.Byte0
risetime_h <b>VAR </b>risetime.Byte1
pulsewidth <b>VAR WORD
</b>pulsewidth_l <b>VAR </b>pulsewidth.Byte0
pulsewidth_h <b>VAR </b>pulsewidth.Byte1

ServoOut <b>VAR </b>GPIO.1
ServoOut = 0
pulse <b>VAR BYTE

</b>TMR0 = 0
pulse = 255
bittest <b>VAR BIT

ASM
</b><font color="#008000">INT_LIST  macro    </font><font color="#000080"><i>; IntSource,        Label,  Type, ResetFlag?
        </i></font><font color="#008000">INT_Handler   TMR0_INT,   PulseOut,   ASM,  yes
        INT_Handler   TMR2_INT,   period,     ASM,  yes
        INT_Handler   CCP1_INT,   PWMeasure,  ASM,  yes
    endm
    INT_CREATE               </font><font color="#000080"><i>; Creates the interrupt processor

    </i></font><font color="#008000">INT_ENABLE  TMR0_INT     </font><font color="#000080"><i>; Enable pulseout interrupts  
    </i></font><font color="#008000">INT_ENABLE  TMR2_INT     </font><font color="#000080"><i>; enable period interrupt (20ms)
    </i></font><font color="#008000">INT_ENABLE  CCP1_INT     </font><font color="#000080"><i>; enable interrupt to increment pulse width (test)
</i></font><b>ENDASM
    PAUSE </b>200
Main:
    <b>PAUSE </b>20
    <font color="#000080"><i>;debug dec pulsewidth,&quot; &quot;,10,13
    </i></font>pulse = ((pulsewidth * 8)/10)-167 <font color="#000080"><i>;scale to fit into a byte
    </i></font>pulse = 255 - pulse               <font color="#000080"><i>;reverse the stick 
    

</i></font><b>GOTO </b>Main

<font color="#000080"><i>'---[TMR0_INT - interrupt handler]------------------------------------------

</i></font><b>ASM
</b><font color="#008000">PulseOut
    btfsc _bittest      </font><font color="#000080"><i>;test status of bittest bit
    </i></font><font color="#008000">goto $+7            </font><font color="#000080"><i>;if high skip 7 lines
    </i></font><font color="#008000">bcf INTCON,5        </font><font color="#000080"><i>;stop timer
    </i></font><font color="#008000">movf _pulse,w       </font><font color="#000080"><i>;load TMR0 with value of pulse variable
    </i></font><font color="#008000">movwf TMR0
    bsf _bittest        </font><font color="#000080"><i>;set bittest bit, indicating we are on second half
    </i></font><font color="#008000">bsf INTCON,5        </font><font color="#000080"><i>;start timer again for second interrupt
    </i></font><font color="#008000">goto $+3            </font><font color="#000080"><i>;skip to return from interrupt
    </i></font><font color="#008000">bcf INTCON,5        </font><font color="#000080"><i>;stop timer
    </i></font><font color="#008000">bcf _ServoOut       </font><font color="#000080"><i>;bring ServoOut pin low for end of pulse width
    </i></font><font color="#008000">INT_RETURN



</font><b>ENDASM
</b><font color="#000080"><i>'---[TMR2_INT - interrupt handler]------------------------------------------
</i></font><b>ASM
</b><font color="#008000">period
    movlw d'72'          </font><font color="#000080"><i>;fine tune timer2 period
    </i></font><font color="#008000">movwf TMR2    
    bcf INTCON,2         </font><font color="#000080"><i>;clear timer flag if set
    </i></font><font color="#008000">movlw d'17'          </font><font color="#000080"><i>;set timer0 first 1ms time base
    </i></font><font color="#008000">movwf TMR0    
    bsf INTCON,5         </font><font color="#000080"><i>;enable timer0 interrupt 
    </i></font><font color="#008000">bsf _ServoOut        </font><font color="#000080"><i>;set ServoOut pin high (begin pulse width)
    </i></font><font color="#008000">bcf _bittest
    INT_RETURN
</font><b>ENDASM
</b><font color="#000080"><i>'---[CCP1_INT - interrupt handler]------------------------------------------
</i></font><b>ASM

</b><font color="#008000">PWMeasure

    BTFSS   CCP1CON, CCP1M0 </font><font color="#000080"><i>; Check for falling edge watch
    </i></font><font color="#008000">GOTO    FALL_EDGE       </font><font color="#000080"><i>; Go pick up the falling edge
    </i></font><font color="#008000">MOVF    CCPR1L,W        </font><font color="#000080"><i>; else store leading edge value
    </i></font><font color="#008000">MOVWF   _risetime_l         </font><font color="#000080"><i>; into 16 bit word risetime
    </i></font><font color="#008000">MOVF    CCPR1H,W
    MOVWF   _risetime_h
    BCF     CCP1CON, CCP1M0 </font><font color="#000080"><i>; Now capture the trailing edge
    </i></font><font color="#008000">GOTO    ISR_2           </font><font color="#000080"><i>; Exit the interrupt service routine
        
</i></font><font color="#008000">FALL_EDGE:
    BSF     CCP1CON, CCP1M0 </font><font color="#000080"><i>; Re-set for trailing edge capture
    </i></font><font color="#008000">MOVF    CCPR1L,W        </font><font color="#000080"><i>; Store the captured value into
    </i></font><font color="#008000">MOVWF   _falltime_l         </font><font color="#000080"><i>; falltime_l and ...
    </i></font><font color="#008000">MOVF    CCPR1H,W
    MOVWF   _falltime_h       </font><font color="#000080"><i>;             ... falltime_h
    ;
    ; 16 bit subtract 
    ;     falltime = falltime - risetime
    ;
    </i></font><font color="#008000">SUB16   _falltime, _risetime   </font><font color="#000080"><i>;do 16 bit subtraction to find width
    </i></font><font color="#008000">movf _falltime_l,w
    movwf _pulsewidth_l
    movf _falltime_h,w
    movwf _pulsewidth_h
ISR_2
    INT_RETURN


</font><b>ENDASM


</b></code></pre><!--EndFragment--></body>
</html>

**Kenjones1935** · - 30th January 2010, 01:43

At last I am getting the correct reference materials.

DS33014K is telling me about MPASM Assembler, Library and Linker.

I have ordered from Belgrade "PIC Microcontrollers". It is being shipped by air. That alone is pretty amazing. Just a little paperback book.

I have also found an online book at:

http://www.mikroe.com/en/books/picmcubook/ch0/

It may be the same book only on line. I am old fashioned. I like to read from paper.

I have plenty of studying to do. Thank you again and again.

Ken

**Kenjones1935** · - 1st February 2010, 02:46

I copied your code snip from POST #73 at 3:02 on the 28th of January.

I noticed in the .asm code that it wanted to:

INCLUDE "MACKRA~1.MAC"

There is no such file in my computer. Do I need a copy? May I have one?

Also the compiler complained that:

Error 118: "Overwriting previous address contents (2007)

Page 157 of DS33014K says that Error 118 occurred because "Code was previously generated for this address" I assume it is talking about address (2007). I do not see where in the .asm code this is happening. I do not even know what to look for.

Ken

**Kenjones1935** · - 1st February 2010, 04:11

Mackrackit,

From what I understand your code will do a PWM every time TMR0 overflows.

What I need to do is make this overflow happen every 20ms. That is 50 pulses per second. We have a 4 meg oscillator. If I were designing this counter I think I would have it set to 20,000 each time it overflows. I gather from page 74 of the Data Sheet that this is not possible. The biggest prescaler is 256.

How about a routine that counts these interrupts until 1/50 of a second has elapsed then calls PWM? I would have it send one pulse out pin 1 with the duty as defined by "duty". It would look like

PWM 1,duty,1

I have found a section on Timers in a book called Running Small Motors with PIC Microcontrollers that has an example of MicroEngineering Labs code that makes an eight digit LCD display the time in hours, minutes and seconds. I think this code must do something like I need.

Ken

**mackrackit** · - 1st February 2010, 11:54

Originally Posted by Kenjones1935

I copied your code snip from POST #73 at 3:02 on the 28th of January.
I noticed in the .asm code that it wanted to:
INCLUDE "MACKRA~1.MAC"
There is no such file in my computer. Do I need a copy? May I have one?

Looks like you have the code named MACKRACKIT?
The *.MAC file is the macro file generated by PBP. It will be in your project directory. The name is chopped to the 8.1? standards.

Also the compiler complained that:
Error 118: "Overwriting previous address contents (2007)
Page 157 of DS33014K says that Error 118 occurred because "Code was previously generated for this address" I assume it is talking about address (2007). I do not see where in the .asm code this is happening. I do not even know what to look for.

Ken

Looks like you are setting the configs in the *.inc file. I have them in the code. Just comment that line out and it should be OK.

**rmteo** · - 28th January 2010, 05:14

Firstly, your PIC16F887 is a 14-bit core device and the ASM manual is here MPASM™ Assembler, MPLINK™ Object
Linker MPLIB™ Object Librarian User’s Guide

Next thing you really need to download is the data sheet PIC16F887

Also, download this FREE book and read it to understand how a PIC works PIC Microcontrollers

The last one is the most useful - I pointed this out to you in an earlier post.

**mackrackit** · - 28th January 2010, 08:02

Ken,
I do not know anything about RC stuff, but here is something to play with.

Code:

<font color="#000080"><i>'16F887 INT RUPT
'44 PIN DEMO BOARD
   </i></font>@ <font color="#0000FF"><b>__config _CONFIG1</b></font>, <font color="#0000FF"><b>_INTRC_OSC_NOCLKOUT </b></font>&amp; <font color="#0000FF"><b>_WDT_ON </b></font>&amp; <font color="#0000FF"><b>_MCLRE_OFF </b></font>&amp; <font color="#0000FF"><b>_LVP_OFF </b></font>&amp; <font color="#0000FF"><b>_CP_OFF
   INTCON</b></font>.<font color="#800000"><b>5 </b></font>= <font color="#800000"><b>1    </b></font><font color="#000080"><i>'ENABLE TMR0  DATA SHEET SECTION 14.3.2
   </i></font><font color="#0000FF"><b>OSCCON </b></font>= <font color="#800000"><b>%01110000 </b></font><font color="#000080"><i>'8 Mhz
   </i></font><font color="#0000FF"><b>OPTION_REG </b></font>= <font color="#800000"><b>%10000111  </b></font><font color="#000080"><i>' 1:256 PRESCALE
   </i></font><font color="#FF0000"><b>ON INTERRUPT GOTO </b></font><font color="#0000FF"><b>TLOOP
   CNT  </b></font><font color="#FF0000"><b>VAR BYTE
   </b></font><font color="#0000FF"><b>D    </b></font><font color="#FF0000"><b>VAR BYTE
   </b></font><font color="#0000FF"><b>D </b></font>= <font color="#800000"><b>0
   
   </b></font><font color="#0000FF"><b>START</b></font>:
   <font color="#FF0000"><b>FOR </b></font><font color="#0000FF"><b>CNT </b></font>= <font color="#800000"><b>0 </b></font><font color="#FF0000"><b>TO </b></font><font color="#800000"><b>150
   </b></font><font color="#FF0000"><b>PWM </b></font><font color="#0000FF"><b>PORTD</b></font>.<font color="#800000"><b>7</b></font>,<font color="#0000FF"><b>D</b></font>,<font color="#800000"><b>100
   </b></font><font color="#0000FF"><b>D </b></font>= <font color="#0000FF"><b>D </b></font>+ <font color="#800000"><b>2
   </b></font><font color="#FF0000"><b>NEXT </b></font><font color="#0000FF"><b>CNT
   </b></font><font color="#FF0000"><b>GOTO </b></font><font color="#0000FF"><b>START
   
   </b></font><font color="#FF0000"><b>DISABLE
   </b></font><font color="#0000FF"><b>TLOOP</b></font>:
   <font color="#0000FF"><b>INTCON</b></font>.<font color="#800000"><b>2</b></font>=<font color="#800000"><b>0 </b></font><font color="#000080"><i>' DATA SHEET SECTION 14.3.2
   </i></font><font color="#FF0000"><b>TOGGLE </b></font><font color="#0000FF"><b>PORTD</b></font>.<font color="#800000"><b>4
   </b></font><font color="#FF0000"><b>RESUME
   ENABLE
</b></font>

**mackrackit** · - 28th January 2010, 08:39

http://www.picbasic.co.uk/forum/showthread.php?t=222
Might also help??

**ScaleRobotics** · - 28th January 2010, 09:34

I had earlier success in getting a servo pulse width to be smooth on a Pic18F2520. But I am now trying to make DT_INTS servo pulse width for a PIC12F683. I have it sweeping from about .95ms to 1.9 ms, but it is not smooth at all. In fact, on the scope, it sometimes switches direction (starts to get wider instead of narrower for a fraction of a second). It is pretty darn ugly in fact.

Any ideas what I might have done (or not done) to cause this?

PIC12f683

Code:

</i></font><b>DEFINE </b>OSC 8
<b>INCLUDE </b><font color="#FF0000">&quot;DT_INTS-14.bas&quot; </font><font color="#000080"><i>;interrupt routines
</i></font><b>INCLUDE </b><font color="#FF0000">&quot;sub16.inc&quot;       </font><font color="#000080"><i>; subtract 16 bit macro

</i></font><b>DEFINE </b>DEBUG_REG	GPIO
<b>DEFINE </b>DEBUG_BIT	0

<b>DEFINE </b>DEBUGIN_BIT	1
<b>DEFINE </b>DEBUG_BAUD	38400
<b>DEFINE </b>DEBUG_MODE	0

INTCON = %10101000 <font color="#000080"><i>'internal oscillator
</i></font>OSCCON = %01110000 <font color="#000080"><i>'set for 8mhz internal
</i></font>CMCON0 = 7 <font color="#000080"><i>'TURN COMPARITORS OFF
</i></font>TRISIO = %010000 <font color="#000080"><i>'Set GSIO 4 INPUT, others to OUTPUT
</i></font>OPTION_REG = %11000010
T1CON = %01000001
T2CON = %01001110
servo <b>VAR </b>GPIO.2
servo = 0
pulse <b>VAR BYTE

</b>pulse = 0
bittest <b>VAR BIT

ASM
</b><font color="#008000">INT_LIST  macro    </font><font color="#000080"><i>; IntSource,        Label,  Type, ResetFlag?
        </i></font><font color="#008000">INT_Handler   TMR0_INT,   PulseOut,   ASM,  yes
        INT_Handler   TMR2_INT,   period,     ASM,  yes
        INT_Handler   TMR1_INT,   test,       ASM,  yes
    endm
    INT_CREATE               </font><font color="#000080"><i>; Creates the interrupt processor

    </i></font><font color="#008000">INT_ENABLE  TMR0_INT     </font><font color="#000080"><i>; Enable pulseout interrupts  
    </i></font><font color="#008000">INT_ENABLE  TMR2_INT     </font><font color="#000080"><i>; enable period interrupt (20ms)
    </i></font><font color="#008000">INT_ENABLE  TMR1_INT     </font><font color="#000080"><i>; enable interrupt to increment pulse width (test)
</i></font><b>ENDASM

</b>Main:
    nop
<b>GOTO </b>Main

<font color="#000080"><i>'---[TMR0_INT - interrupt handler]------------------------------------------

</i></font><b>ASM
</b><font color="#008000">PulseOut
    btfsc _bittest      </font><font color="#000080"><i>;test status of bittest bit
    </i></font><font color="#008000">goto $+7            </font><font color="#000080"><i>;if high skip 7 lines
    </i></font><font color="#008000">bcf OPTION_REG,5    </font><font color="#000080"><i>;stop timer
    </i></font><font color="#008000">movf _pulse,w       </font><font color="#000080"><i>;load TMR0 with value of pulse variable
    </i></font><font color="#008000">movwf TMR0
    bsf _bittest        </font><font color="#000080"><i>;set bittest bit, indicating we are on second half
    </i></font><font color="#008000">bsf OPTION_REG,5    </font><font color="#000080"><i>;start timer again for second interrupt
    </i></font><font color="#008000">goto $+3            </font><font color="#000080"><i>;skip to return from interrupt
    </i></font><font color="#008000">bcf OPTION_REG,5    </font><font color="#000080"><i>;stop timer
    </i></font><font color="#008000">bcf _servo          </font><font color="#000080"><i>;bring servo pin low for end of pulse width
    </i></font><font color="#008000">INT_RETURN

</font><b>ENDASM
</b><font color="#000080"><i>'---[TMR2_INT - interrupt handler]------------------------------------------
</i></font><b>ASM
</b><font color="#008000">period
    bsf _servo          </font><font color="#000080"><i>;set servo pin high (begin pulse width)
    </i></font><font color="#008000">movlw d'0'          </font><font color="#000080"><i>;set timer0 to 0 (full length of timer)
    </i></font><font color="#008000">movwf TMR0    
    bsf OPTION_REG,5    </font><font color="#000080"><i>;start timer0, now PulseOut interrupt will occur
    </i></font><font color="#008000">bcf _bittest        </font><font color="#000080"><i>;clear bittest bit
    </i></font><font color="#008000">INT_RETURN
</font><b>ENDASM
</b><font color="#000080"><i>'---[TMR1_INT - interrupt handler]------------------------------------------
</i></font><b>ASM
</b><font color="#008000">test 
    incf _pulse
    INT_RETURN
</font><b>ENDASM

</b></code></pre><!--EndFragment--></body>
</html>

**Acetronics2** · - 28th January 2010, 12:35

Hi,

I remember some batches of 12F683 did not like the duty value to be changed " on the fly " and needed to stop and restart the CCP module.

Was written on the µChip datasheet ( prior to D release )...

I think some lines about it exist on this forum.

But you don't use the CCP module ...

What I see more is you want to stop Timer0

Code:

bcf OPTION_REG,5    ;stop timer

Option.5 is the TOCS bit ... and that's not a good thing to switch clock to TockI pin ...

Alain

Thread: PBP projects for R/C models

Thread Tools

Search Thread

Display

Hybrid View

I need documentation

12f683 servo pass through

Up to page 19 in DS33014K

mackrackit: where do I get your .INC

I need to send one pulse every 20ms

Why is the pulse width jumping all over?

one idea

Similar Threads

PBP Book

PBP Extensions, What are they?

Compiler differences between PBP 2.33 & 2.46

Newby- PBP wont compile for 18F (MPLAB)

Making PBP code more modular

Members who have read this thread : 1

Bookmarks

Bookmarks

Posting Permissions