Soldering station

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- 6th July 2011, 12:02
fratello

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Soldering station

Using Pensol SL10, one cheap 12F675 and N3310 display, I made for myself this soldering station. Works fine, the mos-fet remains cool, but... I wonder if my code it's the better way to drive the mos-fet and keep most accurate temperature of iron ("pwm mosfet, 255, 300").
Any advice it's wellcome ! Thanks in advance !

Code:

'=============================================================================== '* Statie digitala de lipit, cu display de NOKIA 3310 * '* Digital solering station with N3310 display * '* by Dan Niculescu, june 2011 * '=============================================================================== @ DEVICE PIC12F675, intrc_osc_noclkout, wdt_off, mclr_off DEFINE OSC 4 DEFINE ADC_BITS 10 DEFINE ADC_CLOCK 3 DEFINE ADC_SAMPLEUS 50 CMCON = 7 TRISIO = %001001 INTCON = 0 GPIO = 0 ANSEL = %00010001 ADCON0 = %10000001 wpu = %00000010 D_C var GPIO.2 SDIN var GPIO.4 SCK var GPIO.5 MOSFET var GPIO.1 buton var GPIO.3 LcdReg var byte x var byte y var byte z var byte a var byte PosX var byte PosY var byte Chr var byte LcdData var byte Offset var byte Char var byte adval var word w1 var word vt var word cnt var byte grup var word mode var byte calibra var word i var byte DATA @0,$3E,$51,$49,$45,$3E,_ ' 0 $00,$42,$7F,$40,$00,_ ' 1 $42,$61,$51,$49,$46,_ ' 2 $21,$41,$45,$4B,$31,_ ' 3 $18,$14,$12,$7F,$10,_ ' 4 $27,$45,$45,$45,$39,_ ' 5 $3C,$4A,$49,$49,$30,_ ' 6 $01,$71,$09,$05,$03,_ ' 7 $36,$49,$49,$49,$36,_ ' 8 $06,$49,$49,$29,$1E,_ ' 9 $08,$08,$3E,$08,$08,_ ' + $08,$08,$08,$08,$08,_ ' - $00,$60,$60,$00,$00,_ ' . $00,$02,$05,$02,$00,_ ' grad $3E,$41,$41,$41,$22,_ ' C $7F,$02,$0C,$02,$7F,_ ' M $00,$00,$00,$00,$00,_ ' space $08,$04,$7F,$04,$08,_ ' arrow up $20,$40,$7F,$40,$20 ' arrow down Low D_C 'Command/Data pause 500 LcdReg = %00100001 'LCD Extended Commands. call PrintCtrlLcd LcdReg = $FF 'Set LCD Vop (Contrast).Initial $C5 call PrintCtrlLcd LcdReg = %00000110 'Set Temp coefficent. call PrintCtrlLcd LcdReg = %00010011 'LCD bias mode 1:48. call PrintCtrlLcd LcdReg = %00100000 'LCD Standard Commands call PrintCtrlLcd LcdReg = $0C 'LCD in normal mode. $0D inverse call PrintCtrlLcd Pause 100 Call CursorHome Pause 100 Gosub LCD_Clear mode = 0 Pause 500 ' time to give-up :) '===================== READING VOLTAGE ============================== Main: low mosfet call Borderline pause 50 vt=0 grup=0 for cnt = 1 to 20 ADCON0.1 = 1 WHILE ADCON0.1 = 1 : WEND Pause 10 adval.HighByte = ADRESH adval.LowByte = ADRESL PAUSE 10 vt=adval * 500 vt=div32 1023 grup=vt+grup PAUSE 10 next cnt w1=grup / 20 '===================== setting cursor for display the voltage LcdReg = %10000000 + 25 ' cursor X call PrintCtrlLcd LcdReg = %01000011 ' cursor Y call PrintCtrlLcd '===================== now display results if (w1 dig 2) <1 then char = 16 call Printchar else Char = (w1 dig 2) call PrintChar endif Char = (w1 dig 1) call PrintChar if (w1 dig 0) < 5 then Char = 0 call PrintChar else char = 5 call PrintChar endif Char = 16 call PrintChar Char = 13 call PrintChar Char = 14 call PrintChar if buton = 0 then mode = mode + 1 gosub memo endif gosub check Pause 100 Goto Main '================== L C D =========================================== CursorHome: LcdReg = %10000000 ' cursor Home call PrintCtrlLcd LcdReg = %01000000 ' cursor Home call PrintCtrlLcd return PrintChar: offset = Char * 5 for a = 1 to 5 read offset, LcdReg call PrintDataLcd offset = offset + 1 next a LcdReg = 0 call PrintDataLcd return PrintCtrlLcd: D_C = 0 PrintDataLcd: for x = 1 to 8 SDIN = LcdReg.7 SCK = 1 LcdReg = LcdReg << 1 SCK = 0 next x D_C = 1 return LCD_Clear: PosX=0:PosY=0:Gosub LCD_GotoXY D_C = 1 FOR Chr=1 TO 252 LcdData=0:Gosub LCD_ByteOut LcdData=0:Gosub LCD_ByteOut next Chr return LCD_GotoXY: D_C = 0 LcdData=%01000000 | PosY :Gosub LCD_ByteOut LcdData=%10000000 | PosX :Gosub LCD_ByteOut return LCD_ByteOut: SHIFTOUT SDIN,SCK,1,[LcdData] return GotoXY: LcdReg = %01000000 | Posy : call PrintCtrlLcd 'Y LcdReg = %10000000 | Posx : call PrintCtrlLcd 'X '=============================================================================== memo: if mode = 1 then gosub poz char = 17 call PrintChar calibra = 4800 endif if mode = 2 then gosub poz char = 15 call PrintChar calibra = vt endif if mode = 3 then gosub poz char = 18 call printchar calibra = 10 endif if mode > 3 then mode = 0 gosub poz char = 16 call printchar endif return '=============================================================================== check: if mode >= 1 then if w1 < (calibra-2) then pwm mosfet, 255, 300 else low mosfet endif return '=============================================================================== Poz: LcdReg = %10000000 + 67 ' cursor X call PrintCtrlLcd LcdReg = %01000011 ' cursor Y call PrintCtrlLcd return '=============================================================================== BorderLine: '=================================== RAW UP LcdReg = %10000000 ' cursor X call PrintCtrlLcd LcdReg = %01000000 ' cursor Y call PrintCtrlLcd for y = 0 to 83 LOokup y, [$FF,$01,$01,$01,$01,_ $01,$01,$01,$01,$01,$01,$01,$01,$01,$FD,$FD,$FD,$85,$85,$FD,$FD,$79,_ 'D $01,$01,$FD,$FD,$FD,$01,$01,$79,$FD,$FD,$85,$A5,$ED,$ED,$69,$01,$01,_ 'IG $FD,$FD,$FD,$01,$05,$05,$05,$FD,$FD,$FD,$05,$05,$05,$01,_ 'IT $F9,$FD,$FD,$25,$25,$FD,$FD,$F9,$01,$01,$FD,$FD,$FD,$81,$81,$81,$81,_ 'AL $01,$01,$01,$01,$01,$01,$01,$01,$01,$01,$01,$01,$01,$FF] ,LcdReg call PrintDataLcd next y '=================================== RAW 1 to 4 for i= 1 to 4 posx=0 posy=i gosub GotoXY lcdReg= $FF call PrintDataLcd next i for i = 1 to 4 posx=83 posy=i gosub GotoXY lcdReg= $FF call PrintDataLcd next i '=================================== RAW DOWN LcdReg = %10000000 call PrintCtrlLcd LcdReg = %01000101 call PrintCtrlLcd for y = 0 to 83 LOokup y, [$FF,$80,$80,$80,$80,$80,$80,$80,$80,$80,$80,$80,$80,$80,$80,_ $80,$80,$80,$80,$80,$80,$80,$80,$80,$80,$80,$80,$80,$80,$80,_ $80,$80,$80,$80,$80,$80,$80,$80,$80,$80,$80,$80,$80,$80,$80,_ $80,$80,$80,$80,$80,$80,$80,$80,$80,$80,$80,$80,$80,$80,$80,_ $80,$80,$80,$80,$80,$80,$80,$80,$80,$80,$80,$80,$80,$80,$80,_ $80,$80,$80,$80,$80,$80,$80,$80,$FF] ,LcdReg call PrintDataLcd next y Return '=============================================================================== End 'of program
- 7th July 2011, 05:28
Archangel

Re: Soldering station

:D Hi Fratello,
You REALLY like those Nokia graphic LCD . . . :D
I think they're pretty cool too, Now as for USEFUL comments . . . According to the engineer from France who writes the Dark Side column in Circuit Cellar, . . Robert La Coste ? his suggestion is to use a PID loop to give you some Hysteresis to your temperature to prevent overshoot and undershoot of tip temp. Search the forum there is a pretty good one or more in circulation.
- 7th July 2011, 08:00
fratello

Re: Soldering station

Thanks for advice !
I found this : incPID_mc.pbp Author : Henrik Olsson. GREAT WORK !
Unfortunately the code don't fit in my small 12F675 ; it's a solution to upgrade to a bigger PIC (18F2550 ?) but... for my small device it's another way ?!
...and yes, I like this display : it's verry cheap (about 1 euro) and easy to use. One 2x16 LCD display it's 6 euro and don't look so nice :) .
- 8th July 2011, 02:11
Jerson

Re: Soldering station

I can assume you're almost at the limits of the code space with your current code. The best option, I reckon, to get reasonably good control with your existing setup would be to try PI control. As it is, you are using the PWM function. Just compute the proportional output to get a smoother control.
Modify your check routine so that the PWM function outputs 255 when far lower than the setpoint, 0 when at it. Now, to compensate the offset of the temperature, you add the integral correction over time. This can be achieved quite easily with integer math alone.

A typical P controller pseudo code
Band con 10 ' this decides the band around SetPoint in which you want proportional control

if Temp < SetPoint-Band then
PWMout = 255 ' full heat
else
if Temp > Setpoint+Band then
PWMout = 0 ' full off
else
' within band, do Proportional heating
Error = SetPoint+Band-Temp ' you want to get the bigger numbers for temp < sv
PWMout = (Error*255)/(2*Band) ' get an output from 255 to 0 over the band from SV-Band to SV+Band, 50% at SV
endif
endif

Adding integral is relatively easy too. You just need a variable to adjust the error over time. Or use a button to snapshot the error and add it as an offset.

IntErr var byte

IntErr = IntErr+(Error/IntTime) ' integrate the error over time

PWMout = PWMout + IntErr
if PWMout > 255 then PWMout = 255 ' limit to usable PWM range

PWM Mosfet, PWMout, 300 ' transfer to the mosfet

Just some ideas.
- 8th July 2011, 07:10
fratello

Re: Soldering station

Thank You so much ! I try and I post the results.
- 8th July 2011, 15:44
fratello

Re: Soldering station

I cannot run my simulation ( AMD Athlon64 X2 DualCore 4200+, 2 GB RAM ?!) ...
It's this code OK ? Thanks !

Code:

hyst CON 2 check: if mode >= 1 then if w1 < calibra-hyst then pwm mosfet, 255, 300 if w1 > calibra+hyst then low mosfet if w1 = calibra+hyst-w1 then pwm mosfet,(w1*255)/(2*hyst), 300 endif return
- 9th July 2011, 02:45
Jerson

Re: Soldering station

Looks good to me except I would make the first line this
if w1 < calibra-hyst then high mosfet
- 9th July 2011, 15:15
fratello

Re: Soldering station

Because of "structure" of my code (see memo subroutine) , this procedure don't work :( ... I don't have anymore acces to "memory"... I must try a different way, but I have such little space.
- 11th July 2011, 19:39
fratello

Re: Soldering station

A new, working fine too, version...

Code:

if buton = 0 then mode = mode + 1 gosub memo endif gosub check Pause 100 Goto Main

and

Code:

memo: if mode = 1 then gosub poz char = 17 call PrintChar endif if mode = 2 then gosub poz char = 15 call PrintChar calibra = vt endif if mode = 3 then gosub poz char = 18 call printchar endif if mode > 3 then mode = 0 gosub poz char = 16 call printchar endif return '=============================================================================== check: SELECT CASE MODE CASE 1 PWM MOSFET, 255, 300 CASE 2 if w1 < (calibra-1) then pwm mosfet, 155, 200 else low mosfet endif CASE 3 LOW MOSFET END SELECT

Still have BIG thermal inertia of iron soldering (about 7-8 degree)...
- 12th July 2011, 09:49
SKOLS1

Re: Soldering station

where do you buy Nokia 3310 LCD displays?Can you put a link to the store?Thanks
Do you use Solomon SL-10 soldering iron?
- 12th July 2011, 13:29
fratello

Re: Soldering station

Yes, I use Pensol SL10. The display it's from " people sell everything don't need anymore " :) ... about 1 euro.
- 12th July 2011, 17:41
mister_e

Re: Soldering station

FTR, Nokia 3310 or 5110 are basically the same. they use PCD8544 controller. Seems there's no longer a load of 1-2$ deal 'round here... probably because they are so popular ;)
- 12th July 2011, 18:43
SKOLS1

Re: Soldering station

Quote:

Originally Posted by fratello

Yes, I use Pensol SL10. The display it's from " people sell everything don't need anymore " :) ... about 1 euro.

Which program you use to make the "DIGITAL" text?Can you make a tutorial or something like that so I can learn something.
I buy 3 Nokia 3310 mobile phones for 2euros.And now I have 8 of those in my lab :D
- 12th July 2011, 18:51
HenrikOlsson

Re: Soldering station

Hi,
A fullblown PID is probably overkill but, for the record, incPID_mc is the multichannel version of the PID-filter. It works fine with a single channel but it takes a lot more codespace than the original incPID routine.

You can find v1.5 of the single channel version in this post. And with THAT said it still won't fit the 12F675 due to the limited amount of RAM available in that device.

What I'd do is probably something in the line of what Jerson showed but I'd also add a bias or feedforward based on the setpoint (not the error). If you know that in order to maintain a temperature of say 250°C you need a dutycycle of 40% then, once you're within the window of the regulator you enable the P(I) regulator and add the bias/feedforward to the output.

You'll need to work out a suitable bias/feedforward "gain" since it's not going to be perfectly linear. Since the system (probably) heats up faster than it cools down and you can't have "negative drive" you should err on the low side for the bias/feedforward so that IT alone can never drive the temp OVER the setpoint. If it does the regulator can't bring it down since it can never go "below" 0% PWM.

/Henrik.

EDIT: The original version of incPID, which can be found i post 1 in the thread above, compiles to 314 words on the 12F675 and uses 29 bytes of RAM. Depending on how many bytes of RAM your application uses it MIGHT fit but again, it's probably not worth it.
- 12th July 2011, 18:52
mister_e

Re: Soldering station

probably http://en.radzio.dxp.pl/bitmap_converter/

You draw you screen at the right size (84x48 pixels) in Photoshop, MsPaint (whatever floats your boat), save it as monochrome BMP, then import it in the software, generate the table, then import it in your code.

EDIT: also check this out
http://www.picbasic.co.uk/forum/cont...Nokia-3310-LCD
- 13th July 2011, 02:41
Archangel

Re: Soldering station

Quote:

Originally Posted by HenrikOlsson

Depending on how many bytes of RAM your application uses it MIGHT fit but again, it's probably not worth it.

Hello Henrik,
Probably not in Sweden or the USA, but in Romania, it might be very well worth it. Import tax is high there, wages not so much . . . Thanks for helping him.
JS
- 13th July 2011, 13:35
fratello

Re: Soldering station

Thanks to all for support !!! Glad to see people helping others...
I will take attention to inc_PID, but ... now my code is 1002 words :(. The best (so far) solution it's to "upgrade" the PIC (maybe 18F...) but, for moment, I will try to keep this "low-cost variant".
- 13th July 2011, 14:05
Ioannis

Re: Soldering station

Try to compact your code. Maybe repeated code can be a subroutine etc.

Also if you use flags, then declare them as BIT and not as BYTE or even worse as WORD.

If you need a BYTE variable, do not declare as WORD.

Ioannis
- 13th July 2011, 15:43
fratello

Re: Soldering station

Whitout "graphics elements" the code it's 659 words. Maybe it's a good start for use PID ?! (+314 words)

Code:

' version 2 @ DEVICE PIC12F675, intrc_osc_noclkout, wdt_off, mclr_off DEFINE OSC 4 DEFINE ADC_BITS 10 DEFINE ADC_CLOCK 3 DEFINE ADC_SAMPLEUS 50 CMCON = 7 TRISIO = %001001 INTCON = 0 GPIO = 0 ANSEL = %00010001 ADCON0 = %10000001 wpu = %00000010 D_C var GPIO.2 SDIN var GPIO.4 SCK var GPIO.5 MOSFET var GPIO.1 buton var GPIO.3 LcdReg var byte x var byte y var byte z var byte a var byte PosX var byte PosY var byte Chr var byte LcdData var byte Offset var byte Char var byte adval var word w1 var word vt var word cnt var byte grup var word mode var byte calibra var word DATA @0,$3E,$51,$49,$45,$3E,_ ';// 0 $00,$42,$7F,$40,$00,_ ';// 1 $42,$61,$51,$49,$46,_ ';// 2 $21,$41,$45,$4B,$31,_ ';// 3 $18,$14,$12,$7F,$10,_ ';// 4 $27,$45,$45,$45,$39,_ ';// 5 $3C,$4A,$49,$49,$30,_ ';// 6 $01,$71,$09,$05,$03,_ ';// 7 $36,$49,$49,$49,$36,_ ';// 8 $06,$49,$49,$29,$1E,_ ';// 9 $08,$08,$3E,$08,$08,_ ';// + $08,$08,$08,$08,$08,_ ';// - $00,$60,$60,$00,$00,_ ';// . $00,$02,$05,$02,$00,_ ' grad $3E,$41,$41,$41,$22,_ ' C $7F,$02,$0C,$02,$7F,_ ' M $00,$00,$00,$00,$00,_ ' space $08,$04,$7F,$04,$08,_ ' arrow up $20,$40,$7F,$40,$20 ' arrow down pause 500 LcdReg = %00100001 'LCD Extended Commands. call PrintCtrlLcd LcdReg = $E6 'Set LCD Vop (Contrast).Initial $C5 call PrintCtrlLcd LcdReg = %00000110 'Set Temp coefficent. call PrintCtrlLcd LcdReg = %00010011 'LCD bias mode 1:48. call PrintCtrlLcd LcdReg = %00100000 'LCD Standard Commands call PrintCtrlLcd LcdReg = $0C 'LCD in normal mode. $0D inverse call PrintCtrlLcd Pause 100 Call CursorHome Pause 100 Gosub LCD_Clear mode = 0 Pause 500 ' time to give-up :) '===================== READING VOLTAGE ============================== Main: low mosfet vt=0 grup=0 for cnt = 1 to 20 ADCON0.1 = 1 WHILE ADCON0.1 = 1 : WEND Pause 10 adval.HighByte = ADRESH adval.LowByte = ADRESL PAUSE 10 vt=adval * 500 vt=div32 1023 grup=vt+grup PAUSE 10 next cnt w1=grup / 20 '~~~~~~~~~~~~~~~~~ setting cursor for display the voltage LcdReg = %10000000 + 25 ' cursor X call PrintCtrlLcd LcdReg = %01000011 ' cursor Y call PrintCtrlLcd '~~~~~~~~~~~~~~~~~ now display results if (w1 dig 2) <1 then char = 16 call Printchar else Char = (w1 dig 2) call PrintChar endif Char = (w1 dig 1) call PrintChar if (w1 dig 0) < 5 then Char = 0 call PrintChar else char = 5 call PrintChar endif Char = 16 call PrintChar Char = 13 call PrintChar Char = 14 call PrintChar if buton = 0 then mode = mode + 1 gosub memo endif gosub check Pause 100 Goto Main '================== L C D =========================================== CursorHome: LcdReg = %10000000 ' cursor Home call PrintCtrlLcd LcdReg = %01000000 ' cursor Home call PrintCtrlLcd return PrintChar: offset = Char * 5 for a = 1 to 5 read offset, LcdReg call PrintDataLcd offset = offset + 1 next a LcdReg = 0 call PrintDataLcd return PrintCtrlLcd: D_C = 0 PrintDataLcd: for x = 1 to 8 SDIN = LcdReg.7 SCK = 1 LcdReg = LcdReg << 1 SCK = 0 next x D_C = 1 return LCD_Clear: PosX=0:PosY=0:Gosub LCD_GotoXY D_C = 1 FOR Chr=1 TO 252 LcdData=0:Gosub LCD_ByteOut LcdData=0:Gosub LCD_ByteOut next Chr return LCD_GotoXY: D_C = 0 LcdData=%01000000 | PosY :Gosub LCD_ByteOut LcdData=%10000000 | PosX :Gosub LCD_ByteOut return LCD_ByteOut: SHIFTOUT SDIN,SCK,1,[LcdData] return '=============================================================================== memo: if mode = 1 then gosub poz char = 17 call PrintChar endif if mode = 2 then gosub poz char = 15 call PrintChar calibra = vt endif if mode = 3 then gosub poz char = 18 call printchar endif if mode > 3 then mode = 0 gosub poz char = 16 call printchar endif return '=============================================================================== check: SELECT CASE MODE CASE 1 PWM MOSFET, 255, 300 CASE 2 if w1 < (calibra-1) then pwm mosfet, 155, 200 'era 500 else low mosfet endif CASE 3 LOW MOSFET END SELECT return '=============================================================================== Poz: LcdReg = %10000000 + 67 ' cursor X call PrintCtrlLcd LcdReg = %01000011 ' cursor Y call PrintCtrlLcd return '=============================================================================== End 'of program
- 13th July 2011, 17:31
mister_e

Re: Soldering station

You can still shave some bytes...

- you don't need 2 spi routines LCD_ByteOut & PrintDataLcd,
- replace the For-To-Next loop with Repeat-Until ones,
- if at all possible, try to skip the div32.
- use internal timer for delays (not sure it will that much though
- pwm with a high/low loop maybe?
- select case for a couple a if-then

couples of ideas like that. sounds like a nice challenge ;)
- 13th July 2011, 17:52
mister_e

Re: Soldering station

Another thing about the graphic part, I've messed with it a lot recently and I saved a load of code space by skipping the whole SELCT-CASE + Lookup thing by using something like

Code:

SearchChar: read (index), char if char == TheCharYoureLookingFor then Gosub PrintIt index=endtable endif index=index+6 if (index)<endtable then SearchChar

But you need to modify a little bit the way your DATA lines are done.

Code:

DATA @0,"0",$3E,$51,$49,$45,$3E,_ ';// 0 "1",$00,$42,$7F,$40,$00,_ ';// 1 "2",$42,$61,$51,$49,$46,_ ';// 2 "3",$21,$41,$45,$4B,$31,_ ';// 3 "4",$18,$14,$12,$7F,$10,_ ';// 4 "5",$27,$45,$45,$45,$39,_ ';// 5 "6",$3C,$4A,$49,$49,$30,_ ';// 6 "7",$01,$71,$09,$05,$03,_ ';// 7 "8",$36,$49,$49,$49,$36,_ ';// 8 "9",$06,$49,$49,$29,$1E,_ ';// 9 "+",$08,$08,$3E,$08,$08,_ ';// + "-",$08,$08,$08,$08,$08,_ ';// - ".",$00,$60,$60,$00,$00,_ ';// . "G",$00,$02,$05,$02,$00,_ ' grad "C",$3E,$41,$41,$41,$22,_ ' C "M",$7F,$02,$0C,$02,$7F,_ ' M " ",$00,$00,$00,$00,$00,_ ' space "^",$08,$04,$7F,$04,$08,_ ' arrow up "_",$20,$40,$7F,$40,$20 ' arrow down

so when you want to display your grad character, just need to send G to that routine above. Simple... if it fits the EEPROM ...
- 13th July 2011, 18:16
HenrikOlsson

Re: Soldering station

Hi,
314 words is the size when compiled by itself. Depending on what functions your code uses it might already have one or more of the PBP library routines included meaning the total size will be less than whatever + 314 words.

But like I said, the problem in this case is likely the amount of available RAM. If my count is correct your code uses 23 bytes and the original incPID uses 29 bytes, then, if I'm not mistaken, PBP adds ~24 bytes for its internal use (might change depending on what library routines are used, I don't know for sure). All in all this adds up to more than the 64 bytes of RAM available on the 12F675.

What I meant with not being worth it wasn't that you should throw a "bigger" PIC at the issue. I meant that I don't think the effort of implementing incPID is worth it considering the performance gain you might get compared to the aproaches already discussed. Sure, it it fits it's wort a try, if it doesn't fit I'd try to make do with what's available.

Finally incPID was written in order to be versatile and easy to use. It's probably possible to reduce the size and amount of RAM needed further if adapting it to a specific application - but that's up to anyone using it to do.

/Henrik.
- 14th July 2011, 00:21
cncmachineguy

Re: Soldering station

I'm sure there is something I am missing here but,

Quote:

Still have BIG thermal inertia of iron soldering (about 7-8 degree)...

Do you think you can do better then this? Or need to? Now if its an excersize in learning and just the fun of doing it, well thats a great reason. But I would think the tip temp will cool that much if you just blow on the tip. but to raise it will take full power for a few seconds to get it back, then it will overshoot. Just my HO. :)
- 14th July 2011, 04:24
Archangel

Re: Soldering station

Quote:

Originally Posted by cncmachineguy

I'm sure there is something I am missing here but,

Do you think you can do better then this? Or need to? Now if its an exercise in learning and just the fun of doing it, well that's a great reason. But I would think the tip temp will cool that much if you just blow on the tip. but to raise it will take full power for a few seconds to get it back, then it will overshoot. Just my HO. :)

Just so we are all playing on the same field . . . are we talking degrees C or degrees F ? I am guessing Centigrade so that's more like 13 or 14 Fahrenheit.
Check out Robert's article:
http://itech.fgcu.edu/faculty/zalews...PIDcontrol.pdf
- 14th July 2011, 04:31
mister_e

Re: Soldering station

Sure enough, it's not Kelvin... just sayin :D
- 14th July 2011, 04:35
Archangel

Re: Soldering station

Quote:

Originally Posted by mister_e

Sure enough, it's not Kelvin... just sayin :D

Hey! He (Kelvin) used to work for me . . . :D
- 14th July 2011, 05:23
Jerson

Re: Soldering station

I can hazard a guess that changing this section of code

Code:

vt=adval * 500 vt=div32 1023 grup=vt+grup PAUSE 10

to this

Quote:

vt=adval >> 1
grup=vt+grup
PAUSE 10

might save you a bit of code & ram space. But, I've not checked this, so, you'll beware. Again, if you notice,
I've used an approximation of divide by 2(500/1000) for 500/1023 instead of 1/2.046 I do not think it will matter much if you calibrate
the readings.
- 14th July 2011, 06:24
fratello

Re: Soldering station

Wow ! Great support here ! Thanks to all !!!
In first post You can see : the temperature it's in Celsius degrees. The PID control it's a verry good ideea; sure I will use in future projects !
But...I try to do like Mr. Ioannis :

Code:

if w1 < (calibra - 5) then pwm mosfet 255, 300 if w1 < (calibra - 3) then pwm mosfet 155, 250 if w1 < (calibra - 1) then pwm mosfet 100, 200 endif endif endif

I think to reduce the "power" of heating by adjusting the pwm factors... It's OK ?!
- 14th July 2011, 07:23
Ioannis

Re: Soldering station

1. On the above code you do not need the 3 endif.

2. The credit is not for me. Maybe Jerson's?

Ioannis
- 14th July 2011, 08:58
fratello

Re: Soldering station

Something like this : http://www.picbasic.co.uk/forum/show...7665#post97665
- 14th July 2011, 09:35
Ioannis

Re: Soldering station

Oh, I see. OK, but take into account what I noted on the post.

It is slow and may oscillate. I am sure it will. Also depending on the resolution, the dead band may be large. Of course the larger it is the less it will oscillate.

Ioannis
- 15th July 2011, 08:52
fratello

Re: Soldering station

I wrote this :

Code:

if w1 < (calibra - 3) then pwm mosfet 155, 250 if w1 < (calibra - 1) then pwm mosfet 100, 200

but the heating start ONLY when w1 < (calibra - 3) !
Why don't start when w1 < (calibra - 1) ?!?
- 15th July 2011, 11:10
Ioannis

Re: Soldering station

And what is the value of w1 then?

Ioannis
- 15th July 2011, 12:35
fratello

Re: Soldering station

Example : if calibra (value for memory, set by user) is 140, the heating start at 137.
I wrote the routine for display those two values : w1 (current temperature) and calibra. The led blink ( PWM out) only when w1 < ( (calibra-3) !

Code:

if mode = 2 then call poz char = 16 call PrintChar calibra = vt LcdReg = %10000000 + 25 ' cursor X call PrintCtrlLcd LcdReg = %01000011 + 1 ' cursor Y call PrintCtrlLcd '~~~~~~~~~~~~~~~~~ now display results if (vt dig 2) <1 then char = 16 call Printchar else Char = (vt dig 2) call PrintChar endif Char = (vt dig 1) call PrintChar Char = (vt dig 0) call PrintChar Char = 16 call PrintChar Char = 13 call PrintChar Char = 14 call PrintChar Char = 16 call PrintChar Char = 15 call PrintChar endif
- 4th October 2011, 18:28
SKOLS1

Re: Soldering station

Fratello,can you make a code with MAX6675 thermocouple cold junction sensor?I have one,so I want to use it.
- 4th October 2011, 19:09
fratello

Re: Soldering station

Hi! Why don't You write your own code ?!
- 4th October 2011, 19:37
Byte_Butcher

Re: Soldering station

Quote:

Originally Posted by SKOLS1

Fratello,can you make a code with MAX6675 thermocouple cold junction sensor?I have one,so I want to use it.

Here, I'm familiar with the MAX6675 so I'll give you a start...

This should read the MAX6675 and display degrees C & degrees F on a LCD display.
(Pin aliases for LCD not shown, only for the MAX6675)

Code:

'Alias pins - MAX6675 temp sensor MXSCLK var PORTD.0 'MAX6675 Clock MXCS var PORTD.2 'MAX6675 Chip Select MXSO Var PORTD.3 'MAX6675 Serial Data '--Variables----------------------- kTemp var word 'raw data from MAX6675 tempC var word 'temperature in degrees C tempF var word 'temp C converted to degrees F '-----------Read and display temperature from MAX6675----------- main: LOW MXCS 'chip select low shiftin MXSO, MXSCLK, 0, [kTemp\16] 'shift in the data HIGH MXCS 'chip select high tempC = kTemp >> 5 'side shift to ditch the stuff to the right of the decimal point and just show whole degrees) tempF = ((tempC * 18)/10) + 32 'convert C to F lcdout $fe,1,dec tempC," degrees C ",$fe,$c0,dec tempF," degrees F " 'display the data on LCD pause 500 goto main end
- 5th October 2011, 09:53
fratello

Re: Soldering station

So it's possible to write code for 16F628A (16F648A), for example...since 12F675 don't have enough ports. And working with large fonts (if using Nokia LCD disply) , memory, pre-setting, etc...