PBP projects for R/C models

[cncmachineguy]

see, this is one of the reasons I love this stuff. To do what Walter describes, with the same resources (1 interupt and pulsout), I would set my timer for 20 ms. My int handler would set a flag, and I would get out. Then in my Main, if the flag is set, hit my pulseout routine and clear the flag. This way I would get a new pulse every 20 ms on the dot. But mostly cuz I just always want to get out of the handler. I seem to feel like by name "Interupt" I was busy doing something before I went there. Maybe it was important and I need to get back to it.

As for PBP being guess work, I don't think thats the case. Pulseout/in serout/in and the rest of them, take exactly as long as you think. if you PULSEOUT for 1 ms, thats how long it will take.

[cncmachineguy]

Walter, I like your idea of the 18.5 ms plus servo out to make up the 20ms loop. I need just that for my project. I will want to use 1 timer to control the loop and the pulse, so that seems the best idea to me.

[Kenjones1935]

"Verification of Program Memory failed at address 0x00000000"

I tried some old code that I KNOW loaded. Not today.

I swapped out the PIC. That was not the problem. I reseated all the patch wires. That made no difference.

I restarted the PICKIT2 programmer. That did not help.

I tried with a PICKIT2 board - the one on which I ran the blinkys - no problem. It liked to load and blink.

Where do I start?

Ken

[Kenjones1935]

It was a wire I had added to give the LOGIC TOOL more information. I do not understand why the PICKIT objected. But all is well.

The interrupt driven system sort of works. We'll see more tomorrow.

Thanks again for your help and support.

Ken

[Kenjones1935]

I've got the system working interrupt driven. I do not have proportional controls implemented - yet.

On the bench the car seems as responsive as before. We'll see when I take it to the gym.

One thing I have not figured. How, now, to I disable interrupts when the radio transmitter has been
turned ON? At the very end of this code pack is my old WHILE loop that worked - in the day.

symbol trigright = PORTB.0 ' Define output pin for Trigger pulse
symbol trigfront = PORTB.1 ' Define output pin for Trigger pulse
symbol trigleft  = PORTB.3 ' Define output pin for TRigger pulse
symbol echoright = PORTC.6 ' Define input pin for Echo pulse
symbol echofront = PORTC.5 ' Define input pin for Echo pulse
symbol echoleft  = PORTC.7 ' Define input pin for Echo pulse
SYMBOL channel3  = PORTC.4 ' Define input pin for Channel 3 PWM
' PORTC.0 'High is R/C.  Low is PIC control
TRISC = %11110000
DATA $C0,$0C 'his version's checksum goes here.
define ADC_BITS 8
TRISA.0 = 1 'PORTA.0 as analog input for POT
ANSEL.0 = 1
ADCON1 = %00000000  'left justified 
' We use low eight bits.  0 -> 255.
ADCON0 = %01000001  'divide 4Mhz clock by 8.

'------------
OSCCON = %01100000 '4 Mhz
DEFINE OSC 4

LED1    VAR PORTD.4
wsave VAR BYTE $70 SYSTEM
INCLUDE "DT_INTS-14.bas"     ' Base Interrupt System
INCLUDE "ReEnterPBP.bas"     ' Include if using PBP interrupts

ASM
INT_LIST  macro    ; IntSource,        Label,  Type, ResetFlag?
        INT_Handler   TMR1_INT,  _ToggleLED1,   PBP,  yes
    endm
    INT_CREATE               ; Creates the interrupt processor
ENDASM
      
'------------

'5.0 mSec OR 200 Hz INTERRUPTS
T1CON = %00000001         'Prescaler = 1:1, TMR1ON
'PRELOAD 60543
PreLoad     VAR WORD
PreLoad =  60543
TMR1L = PreLoad.LowByte
TMR1H = PreLoad.HighByte
'@ INT_ENABLE  TMR1_INT     ; enable Timer 1 interrupts

'------------
WHEELS VAR WORD
STEERING VAR WORD

'The following may be a big part of the wall hugging probllem
Potread var word
Forward var word ' was fixed 122. Now sweeps 7 steps. See Checkpot
HalfForward VAR WORD ' Potread/2 +x + 1. See Checkpot
Back VAR WORD 'See Checkpot
HalfBack VAR WORD 'See Checkpot
Brake con 100 'Only used just before Main.

Straight con 150 '?
Right CON 130     '?
HalfRight con 135 '?
QuarterRight CON 140 '?
Left con 170     '?
HalfLeft con 165 '?
QuarterLeft con 160 '?

'---------------------------
frontdanger var word
stopreversing var word
frontfree var word
desiredtrack var word
outertrack var word 

'---------------------------

'some of the following are not used.
CNT  VAR BYTE 'counts interrupts for TRIGGERS
cnt = 0
CNT2  var byte ' counts interrups for wheels and steering
CNT2 = 0
b0 VAR word
rangeright var word
rangeright = 100  'about 6 inches preset
rangefront var word
oldrangeright var word
oldrangefront var word
reversing VAR WORD
reversing = 0
switchtoPIC VAR WORD
switchtoPIC = 1
radiocontrol var word
radiocontrol = 0
steeringleft var word
steeringleft = 0
steeringright var word
steeringright = 0

'-------------------
Checkpot:
' I think Potread goes from 0 to 6.
adcin PORTA.0, Potread
Potread = Potread/37
Forward = 160+Potread
HalfForward = 155+(Potread/2)  'seems to work.
Back = 140-Potread
HalfBack = 145-(Potread/2)
'----------
frontdanger = 210 + Potread*55 '210-540, 14-36 inches 
stopreversing = 180 + Potread*25 '180-330, 12-22 inches
frontfree = 700 + Potread*60 '700-1060, 48-70 inches
desiredtrack = 180 + Potread*20 '180-300, 12-20 inches 
outertrack = 360 + Potread*15 '360-450, 24-30 inches

'----------
write 2, word Potread
write 4, word frontdanger
write 6, word stopreversing
write 8, word frontfree
write 10, WORD desiredtrack
write 12, word outertrack

'-------------------
@ INT_ENABLE  TMR1_INT     ; enable Timer 1 interrupts

'-------------------
low PORTC.0
'hpwm 1,Straight,50
STEERING = Straight
'hpwm 2,Brake,50
WHEELS = Brake
'pause 4000 'Wait so I can put the car down and get out of the way.
'-------------------

main:

CheckIfInDanger:
if rangefront < frontdanger then
STEERING = Straight
WHEELS = back
reversing = 1
goto reverseoutoftrouble
' loop till this is secured
endif 
'-------------------
tryleftturn:
if rangefront < frontfree then
'something ahead - turn hard left.
STEERING = left
WHEELS = halfforward
  steeringleft = 1
 goto main 'loop till this is secured
endif

'------------------- 
goingforward:                          
STEERING = straight
WHEELS = forward

'-------------------
keepgoingforward: '----Compare to right wall
if rangeright > outertrack then
  STEERING = quarterright
endif

if rangeright < desiredtrack and oldrangeright < rangeright then
  STEERING = STRAIGHT
endif 
  
if rangeright > desiredtrack and oldrangeright > rangeright then
  STEERING = STRAIGHT
endif

if rangeright > desiredtrack and oldrangeright < rangeright then
  STEERING = QUARTERRIGHT
endif

if rangeright < desiredtrack and oldrangeright >= rangeright then
  STEERING = QUARTERLEFT
endif

goto main

'-------------------------
reverseoutoftrouble:
while rangefront < stopreversing
  STEERING = RIGHT
  WHEELS = RIGHT
wend 

if rangeright > outertrack or rangeright < desiredtrack then 
  STEERING = LEFT
  steeringleft = 1
  WHEELS = HALFFORWARD
endif
goto main

'***********INTERRUPT HANDLER************
ToggleLED1: 
TMR1L = PreLoad.LowByte   ' Load the timer with preload value.
TMR1H = PreLoad.HighByte
TOGGLE LED1

'------------
' Trigger SONAR alternatively every 25 interrupts
if CNT=25 then
 pulsr:
 oldrangeright = rangeright
' produce 10uS trigger pulse (must be minimum of 10uS)
 low trigright
 HIGH trigright
 high trigright
 high trigright
 LOW trigright
'zero could be legal below
 pulsin echoright,1,rangeright 'measures the range in 10uS steps
 endif

'-------------
if CNT=50 then
 pulsf: 
 oldrangefront = rangefront 
 low trigfront
 hIGH trigfront
 high trigfront
 high trigfront
 LOW trigfront
 pulsin echofront,1,rangefront ' measures the range in 10uS steps
 CNT=0
endif
 CNT=CNT+1

'--------------
if cnt2=4  then
' PWM pulses are between 1 and 2 millisec.
    low PORTC.1
    low PORTC.2
    pulsout PORTC.1,WHEELS  
    PULSOUT PORTC.2,STEERING   
    CNT2=0
endif
CNT2=CNT2+1
    
@ INT_RETURN
checkchannel3:
'works with four AA batteries pack. Radio receiver puts pulses
'on this line whenever the transmitter is turned ON.
 switchtoPIC = 2
 while switchtoPIC >= 2
    count channel3,65,switchtoPIC
    high portc.0
 wend
   low portc.0   
      
end

[cncmachineguy]

@ INT_ENABLE  TMR1_INT     ; enable Timer 1 interrupts

that line turns the interupt on, or enables it. there must be a simular line like INT_DISABLE maybe to turn it off.
turn it off when the while loop is true, or when under Tx control. then turn it back on when Tx control is over.

[Kenjones1935]

For some reason disabling interrupt during the WHILE loop did not work. I could have done
something stupid.

What I want to know is where is the list of "blocking" commands. I do not see such a list in
my PBP book. For example, is COUNT a blocker?

Here is what I coded immediately after main:
main:

'-------------------

checkchannel3:
'worked with four AA batteries pack. Radio receiver puts pulses
'on this line whenever the transmitter is turned ON.
switchtoPIC = 2
while switchtoPIC >= 2
@ INT_DISABLE TMR1_INT
count channel3,65,switchtoPIC
high portc.0
wend
low portc.0
@ INT_ENABLE TMR1_INT

Ken