Need some advice.

[cphillips82]

thanks for your reply s. here is a piece of software I'm using just to see if I can get it working without the flicker of when temp hits 5000 and 10000, so far failed, I'm using a moc 3021 and a bt137 and bridge with a 1k feeding porta.0 and a 10k holding it low. I have been able to make a simple dimming program so I know this hardware works, I also have an lcd so I need a few more io that a 12f675

Define LCD_DREG PORTB
 'Set starting data bit
 Define LCD_DBIT 4 'rb4,rb5,rb6,rb7
 'Set LCD RS Port
 DEFINE LCD_RSREG portb
 'Set LCD RS Bit
 define LCD_RSBIT 3
 'Set LCD Enable Port
 Define LCD_EREG portb
 'Set LCD Enable Bit
 Define LCD_EBIT 2
 'Set number of LCD Lines
 Define LCD_LINES 2
 'Set Command Delay time in uS
 define LCD_COMMANUS 2000
 'Set Data delay time in uS
 define LCD_DATAUS 50

temp var word
temp = 0
temp2 var word
target var word
target = 3000
symbol fire = portb.1
symbol ac = portb.0

maxdelay var word
maxdelay = 8000

delay var word
delay = 4000

trisa = %00000011
trisb = %00000001

DQ	VAR	PORTa.0			' One-wire data pin
temperature VAR	WORD			' Temperature storage
count_remain VAR BYTE			' Count remaining
count_per_c VAR	BYTE

DS18B20_9bit CON %00011111 ; 93.75ms, 0.5°C
DS18B20_10bit CON %00111111 ; 187.5ms, 0.25°C <-- My favorite
DS18B20_11bit CON %01011111 ; 375ms, 0.125°C
DS18B20_12bit CON %01111111 ; 750ms, 0.0625°C (default)

OWOUT DQ, 1, [$CC, $4E, 0, 0, DS18B20_11bit]
 


lcdout 254,1
pause 100

on interrupt goto firetriac
intcon = %10010000

mainloop:
for temp = 0 to 10000
if temp = 5000 then
gosub startcon
endif
if temp = 10000 then
gosub readtemp
endif
next temp
goto mainloop 




disable
firetriac:
pauseus  delay
fire = 1
pauseus 10
fire = 0
intcon.1 = 0
resume
enable

startcon:
OWOut DQ, 1, [$CC, $44]       ' Start temperature conversion
return
readtemp:


waitloop: OWIn DQ, 4, [count_remain]	' Check for still busy converting
	IF count_remain = 0 Then mainloop    'was this what you ment about no waiting in the 'loop

	OWOut DQ, 1, [$CC, $BE]		' Read the temperature
        OWIn DQ, 0, [temperature.LOWBYTE, temperature.HIGHBYTE, Skip 4, count_remain, count_per_c]

	' Calculate temperature in degrees C to 2 decimal places (not valid for negative temperature)
	temperature = (temperature >> 1)

	lcdout 254,1, dec temperature / 10 ,".", dec1 temperature , " c" 
    lcdout 254,192, dec delay 

return

[cphillips82]

what I want to do over all is to dim an incandescent light depending what temperature it is without an annoying flicker while fetching the temp.

[mister_e]

You may try to switch to asm interrupt or Darrel's instant interrupt to see if it works better.

A real schematic would help...

To generate 10uSec with PAUSEUS, you need at least a 10MHz crystal. If you're using a 4MHz, you'll need to use asm NOP or GOTO

A scope is handy for those things. 1 channel on the Main AC, the other on the PIC output... now you see if you're really in-synch. Be careful if you do that, unless we might see some smoke messages

[cphillips82]

my interup seems to work fine it just that the owin owout commands seem to really take alot of time and the interupts are missed in the process. i'll try to draw up a schematic.

[cphillips82]

here is a quick diagram, I know thats not a moc3021

[cphillips82]

here abit smaller

[mister_e]

my interup seems to work fine it just that the owin owout commands seem to really take alot of time and the interupts are missed in the process. i'll try to draw up a schematic.

This is why i've suggested to use Darrel's instant interrupts

[Acetronics2]

Hi,

The MOC 3041 ( and not 3021 ...) permitted to avoid all the zero detection AND the interrupts ...

burst mode is really not a problem with heating systems ...

Alain

[cphillips82]

not too sure what you mean "burst mode" is that like on 1 sec off 4 secon = 20% heat?. I'll try instant interupt but I'm a little affraid of asm..... I hate it!