-
Notifications
You must be signed in to change notification settings - Fork 0
/
Copy pathreflowOvenController.ino
1139 lines (997 loc) · 34 KB
/
reflowOvenController.ino
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
/*******************************************************************************
* Title: Reflow Oven Controller
* Version: 1.20
* Date: 26-11-2012
* Company: Rocket Scream Electronics
* Author: Lim Phang Moh
* Website: www.rocketscream.com
*
* Brief
* =====
* This is an example firmware for our Arduino compatible reflow oven controller.
* The reflow curve used in this firmware is meant for lead-free profile
* (it's even easier for leaded process!). You'll need to use the MAX31855
* library for Arduino if you are having a shield of v1.60 & above which can be
* downloaded from our GitHub repository. Please check our wiki
* (www.rocketscream.com/wiki) for more information on using this piece of code
* together with the reflow oven controller shield.
*
* Temperature (Degree Celcius) Magic Happens Here!
* 245-| x x
* | x x
* | x x
* | x x
* 200-| x x
* | x | | x
* | x | | x
* | x | |
* 150-| x | |
* | x | | |
* | x | | |
* | x | | |
* | x | | |
* | x | | |
* | x | | |
* 30 -| x | | |
* |< 60 - 90 s >|< 90 - 120 s >|< 90 - 120 s >|
* | Preheat Stage | Soaking Stage | Reflow Stage | Cool
* 0 |_ _ _ _ _ _ _ _|_ _ _ _ _ _ _ _ _ _|_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
* Time (Seconds)
*
* This firmware owed very much on the works of other talented individuals as
* follows:/*******************************************************************************
Title: Tiny Reflow Controller
Version: 2.00
Date: 03-03-2019
Company: Rocket Scream Electronics
Author: Lim Phang Moh
Website: www.rocketscream.com
Brief
=====
This is an example firmware for our Arduino compatible Tiny Reflow Controller.
A big portion of the code is copied over from our Reflow Oven Controller
Shield. We added both lead-free and leaded reflow profile support in this
firmware which can be selected by pressing switch #2 (labelled as LF|PB on PCB)
during system idle. The unit will remember the last selected reflow profile.
You'll need to use the MAX31856 library for Arduino.
Lead-Free Reflow Curve
======================
Temperature (Degree Celcius) Magic Happens Here!
245-| x x
| x x
| x x
| x x
200-| x x
| x | | x
| x | | x
| x | |
150-| x | |
| x | | |
| x | | |
| x | | |
| x | | |
| x | | |
| x | | |
30 -| x | | |
|< 60 - 90 s >|< 90 - 120 s >|< 90 - 120 s >|
| Preheat Stage | Soaking Stage | Reflow Stage | Cool
0 |_ _ _ _ _ _ _ _|_ _ _ _ _ _ _ _ _ _|_ _ _ _ _ _ _ _ _ _ _ _ _ |_ _ _ _ _
Time (Seconds)
Leaded Reflow Curve (Kester EP256)
==================================
Temperature (Degree Celcius) Magic Happens Here!
219-| x x
| x x
| x x
180-| x x
| x | | x
| x | | x
150-| x | | x
| x | | |
| x | | |
| x | | |
| x | | |
| x | | |
| x | | |
30 -| x | | |
|< 60 - 90 s >|< 60 - 90 s >|< 60 - 90 s >|
| Preheat Stage | Soaking Stage| Reflow Stage | Cool
0 |_ _ _ _ _ _ _ _|_ _ _ _ _ _ _ |_ _ _ _ _ _ _ _ _ _ |_ _ _ _ _ _ _ _ _ _ _
Time (Seconds)
This firmware owed very much on the works of other talented individuals as
follows:
==========================================
Brett Beauregard (www.brettbeauregard.com)
==========================================
Author of Arduino PID library. On top of providing industry standard PID
implementation, he gave a lot of help in making this reflow oven controller
possible using his awesome library.
==========================================
Limor Fried of Adafruit (www.adafruit.com)
==========================================
Author of Arduino MAX31856 and SSD1306 libraries. Adafruit has been the source
of tonnes of tutorials, examples, and libraries for everyone to learn.
==========================================
Spence Konde (www.drazzy.com/e/)
==========================================
Maintainer of the ATtiny core for Arduino:
https://github.com/SpenceKonde/ATTinyCore
Disclaimer
==========
Dealing with high voltage is a very dangerous act! Please make sure you know
what you are dealing with and have proper knowledge before hand. Your use of
any information or materials on this Tiny Reflow Controller is entirely at
your own risk, for which we shall not be liable.
Licences
========
This Tiny Reflow Controller hardware and firmware are released under the
Creative Commons Share Alike v3.0 license
http://creativecommons.org/licenses/by-sa/3.0/
You are free to take this piece of code, use it and modify it.
All we ask is attribution including the supporting libraries used in this
firmware.
Required Libraries
==================
- Arduino PID Library:
>> https://github.com/br3ttb/Arduino-PID-Library
- Adafruit MAX31856 Library:
>> https://github.com/adafruit/Adafruit_MAX31856
- Adafruit SSD1306 Library:
>> https://github.com/adafruit/Adafruit_SSD1306
- Adafruit GFX Library:
>> https://github.com/adafruit/Adafruit-GFX-Library
Revision Description
======== ===========
2.00 Support V2 of the Tiny Reflow Controller:
- Based on ATMega328P 3.3V @ 8MHz
- Uses SSD1306 128x64 OLED
1.00 Initial public release:
- Based on ATtiny1634R 3.3V @ 8MHz
- Uses 8x2 alphanumeric LCD
*******************************************************************************/
#define VERSION 2 // Replace with 1 or 2 *-**********************************************************
// ***** INCLUDES *****
#include <Arduino.h>
#include <SPI.h>
#include <Wire.h>
#include <EEPROM.h>
#if VERSION == 1
#include <Adafruit_LiquidCrystal.h> // updated
#elif VERSION == 2
#include <Adafruit_GFX.h> // Comment for VERSION 1
#include <Adafruit_SSD1306.h> // Comment for VERSION 1
#endif
//#include <Adafruit_MAX31856.h>
#include <Adafruit_MAX31855.h>
//#include <MAX31855.h>
#include <PID_v1.h>
#include "main.h"
// ***** TYPE DEFINITIONS *****
typedef enum REFLOW_STATE
{
REFLOW_STATE_IDLE,
REFLOW_STATE_PREHEAT,
REFLOW_STATE_SOAK,
REFLOW_STATE_REFLOW,
REFLOW_STATE_COOL,
REFLOW_STATE_COMPLETE,
REFLOW_STATE_TOO_HOT,
REFLOW_STATE_ERROR
} reflowState_t;
typedef enum REFLOW_STATUS
{
REFLOW_STATUS_OFF,
REFLOW_STATUS_ON
} reflowStatus_t;
typedef enum SWITCH
{
SWITCH_NONE,
SWITCH_1,
SWITCH_2
} switch_t;
typedef enum DEBOUNCE_STATE
{
DEBOUNCE_STATE_IDLE,
DEBOUNCE_STATE_CHECK,
DEBOUNCE_STATE_RELEASE
} debounceState_t;
typedef enum REFLOW_PROFILE
{
REFLOW_PROFILE_LEADFREE,
REFLOW_PROFILE_LEADED
} reflowProfile_t;
// ***** CONSTANTS *****
// ***** GENERAL *****
const char compile_date[] = __DATE__ " " __TIME__;
// ***** GENERAL PROFILE CONSTANTS *****
#define PROFILE_TYPE_ADDRESS 0
#define TEMPERATURE_ROOM 50
#define TEMPERATURE_SOAK_MIN 150
#define TEMPERATURE_COOL_MIN 100
#define SENSOR_SAMPLING_TIME 1000
#define SOAK_TEMPERATURE_STEP 5
// ***** LEAD FREE PROFILE CONSTANTS *****
#define TEMPERATURE_SOAK_MAX_LF 200
#define TEMPERATURE_REFLOW_MAX_LF 250
#define SOAK_MICRO_PERIOD_LF 9000
// ***** LEADED PROFILE CONSTANTS *****
#define TEMPERATURE_SOAK_MAX_PB 180
#define TEMPERATURE_REFLOW_MAX_PB 224
#define SOAK_MICRO_PERIOD_PB 10000
// ***** SWITCH SPECIFIC CONSTANTS *****
#define DEBOUNCE_PERIOD_MIN 100
// ***** DISPLAY SPECIFIC CONSTANTS *****
#define UPDATE_RATE 100
// ***** PID PARAMETERS *****
// ***** PRE-HEAT STAGE *****
#define PID_KP_PREHEAT 100
#define PID_KI_PREHEAT 0.025
#define PID_KD_PREHEAT 20
// ***** SOAKING STAGE *****
#define PID_KP_SOAK 300
#define PID_KI_SOAK 0.05
#define PID_KD_SOAK 250
// ***** REFLOW STAGE *****
#define PID_KP_REFLOW 300
#define PID_KI_REFLOW 0.05
#define PID_KD_REFLOW 350
#define PID_SAMPLE_TIME 1000
#if VERSION == 2
#define SCREEN_WIDTH 128 // OLED display width, in pixels
#define SCREEN_HEIGHT 64 // OLED display height, in pixels
#define X_AXIS_START 18 // X-axis starting position
#endif
// ***** LCD MESSAGES *****
const char* lcdMessagesReflowStatus[] = {
"Ready",
"Pre",
"Soak",
"Reflow",
"Cool",
"Done!",
"Hot!",
"Error"
};
// ***** DEGREE SYMBOL FOR LCD *****
unsigned char degree[8] = {
140, 146, 146, 140, 128, 128, 128, 128
};
// ***** PIN ASSIGNMENT *****
#if VERSION == 1
unsigned char ssrPin = 46;
unsigned char thermocoupleCSPin = 10; //48
unsigned char lcdRsPin = 8; //9
unsigned char lcdEPin = 9; //9
unsigned char lcdD4Pin = 4; //4
unsigned char lcdD5Pin = 5; //5
unsigned char lcdD6Pin = 6; // 6
unsigned char lcdD7Pin = 7; // 7
unsigned char buzzerPin = 44; // 44
unsigned char switchPin = A0; // A0
//unsigned char ledPin = LED_BUILTIN;
unsigned char ledPin = 4;
#elif VERSION == 2
unsigned char ssrPin = A0; //46
unsigned char ssrPinBottom = A1;
unsigned char fanPin = A2; // A1
unsigned char thermocoupleCSPin = 4; // 48, 10
unsigned char ledPin = 6; // 4
unsigned char buzzerPin = 9; // 44
unsigned char switchStartStopPin = 3; // 3
unsigned char switchLfPbPin = 5; //2
#endif
// ***** PID CONTROL VARIABLES *****
double setpoint;
double input;
double output;
double kp = PID_KP_PREHEAT;
double ki = PID_KI_PREHEAT;
double kd = PID_KD_PREHEAT;
int windowSize;
unsigned long windowStartTime;
unsigned long nextCheck;
unsigned long nextRead;
unsigned long updateLcd;
unsigned long timerSoak;
unsigned long buzzerPeriod;
unsigned char soakTemperatureMax;
unsigned char reflowTemperatureMax;
unsigned long soakMicroPeriod;
// Reflow oven controller state machine state variable
reflowState_t reflowState;
// Reflow oven controller status
reflowStatus_t reflowStatus;
// Reflow profile type
reflowProfile_t reflowProfile;
// Switch debounce state machine state variable
debounceState_t debounceState;
// Switch debounce timer
long lastDebounceTime;
// Switch press status
switch_t switchStatus;
switch_t switchValue;
switch_t switchMask;
// Seconds timer
unsigned int timerSeconds;
// Thermocouple fault status
//unsigned char fault;
uint8_t fault;
#if VERSION == 2 // for some reason this was set to ifdef???
unsigned int timerUpdate;
unsigned char temperature[SCREEN_WIDTH - X_AXIS_START];
unsigned char x;
#endif
// PID control interface
PID reflowOvenPID(&input, &output, &setpoint, kp, ki, kd, DIRECT);
#if VERSION == 1
// LCD interface
Adafruit_LiquidCrystal lcd(lcdRsPin, lcdEPin, lcdD4Pin, lcdD5Pin, lcdD6Pin, lcdD7Pin); // added Adafruit_
#elif VERSION == 2
Adafruit_SSD1306 oled(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire);
#endif
/*
* Deal with the different stupid thermocopuple interfaces
*
* Note that the cheap ali express version of the max31855 seems to be missing a few things
* it is NOT 5 v tollerant, it might like max of 4 v. Also needs a bypass capacitor on the thermocouple
* I think they said 10 microfarad.
* Shoudl really have a level shifter/logic converter
*/
#ifdef ADAFRUIT_MAX31856_H
Adafruit_MAX31856 thermocouple = Adafruit_MAX31856(thermocoupleCSPin);
#elif defined(ADAFRUIT_MAX31855_H)
Adafruit_MAX31855 thermocouple = Adafruit_MAX31855(thermocoupleCSPin);
//Adafruit_MAX31855 thermocouple = Adafruit_MAX31855(hermocoupleCSPin, SPI1); // not really sure
#endif
void MAX_Initialize(void){
Serial.println("Initialize Thermocouple Interface...");
thermocouple.begin(); // Initialize thermocouple interface
#ifdef ADAFRUIT_MAX31855_H
#elif ADAFRUIT_MAX31856_H
//delay(2);
thermocouple.setThermocoupleType(MAX31856_TCTYPE_K);
thermocouple.setColdJunctionFaultThreshholds(0, 500);
thermocouple.setTempFaultThreshholds(0, 500);
Serial.print("Thermocouple type: ");
switch (thermocouple.getThermocoupleType() ) {
case MAX31856_TCTYPE_B: Serial.println("B Type"); break;
case MAX31856_TCTYPE_E: Serial.println("E Type"); break;
case MAX31856_TCTYPE_J: Serial.println("J Type"); break;
case MAX31856_TCTYPE_K: Serial.println("K Type"); break;
case MAX31856_TCTYPE_N: Serial.println("N Type"); break;
case MAX31856_TCTYPE_R: Serial.println("R Type"); break;
case MAX31856_TCTYPE_S: Serial.println("S Type"); break;
case MAX31856_TCTYPE_T: Serial.println("T Type"); break;
case MAX31856_VMODE_G8: Serial.println("Voltage x8 Gain mode"); break;
case MAX31856_VMODE_G32: Serial.println("Voltage x8 Gain mode"); break;
default: Serial.println("Unknown"); break;
}
#endif
}
double MAX_GetTemp(void) {
double _tempreading, _tempreading_internal;
uint8_t _fault;
#ifdef ADAFRUIT_MAX31855_H
_tempreading_internal = thermocouple.readInternal();
_tempreading = thermocouple.readCelsius();
// Maybe just try and read a fault here?
if (isnan(_tempreading)) {
Serial.println("Thermocouple fault(s) detected!");
uint8_t e = thermocouple.readError();
if (e & MAX31855_FAULT_OPEN) Serial.println("FAULT: Thermocouple is open - no connections.");
if (e & MAX31855_FAULT_SHORT_GND) Serial.println("FAULT: Thermocouple is short-circuited to GND.");
if (e & MAX31855_FAULT_SHORT_VCC) Serial.println("FAULT: Thermocouple is short-circuited to VCC.");
} else {
//Serial.print("C:"); Serial.print(input);
//Serial.print("\tInternal:"); Serial.println(_tempreading_internal);
}
#elif defined(ADAFRUIT_MAX31856_H)
_tempreading = thermocouple.readThermocoupleTemperature();
_fault = thermocouple.readFault(); // Check for thermocouple fault
if (fault) {
if (fault & MAX31856_FAULT_CJRANGE) Serial.println("Cold Junction Range Fault");
if (fault & MAX31856_FAULT_TCRANGE) Serial.println("Thermocouple Range Fault");
if (fault & MAX31856_FAULT_CJHIGH) Serial.println("Cold Junction High Fault");
if (fault & MAX31856_FAULT_CJLOW) Serial.println("Cold Junction Low Fault");
if (fault & MAX31856_FAULT_TCHIGH) Serial.println("Thermocouple High Fault");
if (fault & MAX31856_FAULT_TCLOW) Serial.println("Thermocouple Low Fault");
if (fault & MAX31856_FAULT_OVUV) Serial.println("Over/Under Voltage Fault");
if (fault & MAX31856_FAULT_OPEN) Serial.println("Thermocouple Open Fault");
}
#endif
//Serial.print("Temp:");Serial.println(input); Serial.println(F("")); // Debug Temperature
return _tempreading;
}
/*
// check rotary encoder; set temperature, toggle boost mode, enter setup menu accordingly
uint16_t SetTemp, ShowTemp, gap, Step;
// reads current rotary encoder value
int getRotary() {
return (count >> ROTARY_TYPE);
}
void ROTARYCheck() {
// set working temperature according to rotary encoder value
SetTemp = getRotary();
// check rotary encoder switch
uint8_t c = digitalRead(BUTTON_PIN);
if ( !c && c0 ) {
beep();
buttonmillis = millis();
while( (!digitalRead(BUTTON_PIN)) && ((millis() - buttonmillis) < 500) );
if ((millis() - buttonmillis) >= 500) SetupScreen();
else {
inBoostMode = !inBoostMode;
if (inBoostMode) boostmillis = millis();
handleMoved = true;
}
}
c0 = c;
// check timer when in boost mode
if (inBoostMode && timeOfBoost) {
goneSeconds = (millis() - boostmillis) / 1000;
if (goneSeconds >= timeOfBoost) {
inBoostMode = false; // stop boost mode
beep(); // beep if boost mode is over
beepIfWorky = true; // beep again when working temperature is reached
}
}
}
*/
void tone_error(void) {
for (int i=0; i < 10; i++) {
tone(buzzerPin, 2000,50);
delay(100);
}
digitalWrite(buzzerPin, LOW);
}
void tone_beep(void) {
tone(buzzerPin, 2000,50);
delay(100);
digitalWrite(buzzerPin, LOW);
}
void tone_start(void) {
tone(buzzerPin, 1000,200);
delay(200);
tone(buzzerPin, 2000,200);
delay(200);
tone(buzzerPin, 3000,200);
delay(200);
digitalWrite(buzzerPin, LOW);
}
void tone_finish(void) {
tone(buzzerPin, 3000,200);
delay(200);
tone(buzzerPin, 2000,200);
delay(200);
tone(buzzerPin, 2000,200);
delay(200);
digitalWrite(buzzerPin, LOW);
}
void setup()
{
Serial.begin(115200); // Serial communication at 115200 bps
Serial.println("Reflow Oven started");
// Check current selected reflow profile
unsigned char value = EEPROM.read(PROFILE_TYPE_ADDRESS);
if ((value == 0) || (value == 1))
{
// Valid reflow profile value
reflowProfile = value;
}
else
{
// Default to lead-free profile
EEPROM.write(PROFILE_TYPE_ADDRESS, 0);
reflowProfile = REFLOW_PROFILE_LEADFREE;
}
// SSR pin initialization to ensure reflow oven is off
digitalWrite(ssrPin, LOW);
pinMode(ssrPin, OUTPUT);
digitalWrite(ssrPinBottom, LOW);
pinMode(ssrPinBottom, OUTPUT);
// Buzzer pin initialization to ensure annoying buzzer is off
digitalWrite(buzzerPin, LOW);
pinMode(buzzerPin, OUTPUT);
// LED pins initialization and turn on upon start-up (active high)
pinMode(ledPin, OUTPUT);
digitalWrite(ledPin, HIGH);
// setup pins
pinMode(switchStartStopPin,INPUT_PULLUP);
pinMode(switchLfPbPin,INPUT_PULLUP);
// Start-up splash
//digitalWrite(buzzerPin, HIGH);
#if VERSION == 1
Serial.println("Initialize LCD...");
lcd.begin(8, 2);
lcd.createChar(0, degree);
lcd.clear();
lcd.print(F(" Tiny "));
lcd.setCursor(0, 1);
lcd.print(F(" Reflow "));
#elif VERSION == 2
Serial.println("Initialize OLED...");
if(!oled.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
//if(!oled.begin(0x3C)) {
Serial.println(F("SSD1306 Allocation failed"));
for(;;); // loop forever
}
//oled.begin(SSD1306_SWITCHCAPVCC, 0x3C);
oled.display();
#endif
tone_start(); // why not
//digitalWrite(buzzerPin, LOW);
delay(2000); // Needed for the display, should show us a splash screen for the OLED
#if VERSION == 1
lcd.clear();
lcd.print(F(" v1.00 "));
lcd.setCursor(0, 1);
lcd.print(F("26-07-17"));
delay(2000);
lcd.clear();
#elif VERSION == 2
Serial.println("Display Start Message on OLED...");
oled.clearDisplay();
oled.setTextSize(1);
oled.setTextColor(WHITE);
oled.setCursor(0, 0);
oled.println(F(" Tiny Reflow"));
oled.println(F(" Controller"));
oled.println();
oled.println(F(" v2.00"));
oled.println();
oled.println(F(" 04-03-19"));
oled.display();
delay(3000);
Serial.println("Clear Display OLED...");
oled.clearDisplay();
#endif
// Turn off LED (active high)
digitalWrite(ledPin, LOW);
// Set window size
windowSize = 2000;
// Initialize time keeping variable
nextCheck = millis();
// Initialize thermocouple reading variable
nextRead = millis();
// Initialize LCD update timer
updateLcd = millis();
MAX_Initialize();
}
void loop()
{
// Current time
unsigned long now;
// Time to read thermocouple?
if (millis() > nextRead)
{
// Read thermocouple next sampling period
nextRead += SENSOR_SAMPLING_TIME;
input = MAX_GetTemp(); // Read current temperature
if (isnan(input)) {
reflowState = REFLOW_STATE_ERROR;
reflowStatus = REFLOW_STATUS_OFF;
Serial.println(F("Error"));
}
}
if (millis() > nextCheck)
{
// Check input in the next seconds
nextCheck += SENSOR_SAMPLING_TIME;
// If reflow process is on going
if (reflowStatus == REFLOW_STATUS_ON)
{
// Toggle red LED as system heart beat
digitalWrite(ledPin, !(digitalRead(ledPin)));
// Increase seconds timer for reflow curve plot
timerSeconds++;
// Send temperature and time stamp to serial
Serial.print(timerSeconds);
Serial.print(F(","));
Serial.print(setpoint);
Serial.print(F(","));
Serial.print(input);
Serial.print(F(","));
Serial.println(output);
}
else
{
// Turn off red LED
digitalWrite(ledPin, LOW);
}
}
if (millis() > updateLcd)
{
// Update LCD in the next 100 ms
updateLcd += UPDATE_RATE;
#if VERSION == 1
// Clear LCD
lcd.clear();
// Print current system state
lcd.print(lcdMessagesReflowStatus[reflowState]);
lcd.setCursor(6, 0);
if (reflowProfile == REFLOW_PROFILE_LEADFREE)
{
lcd.print(F("LF"));
}
else
{
lcd.print(F("PB"));
}
lcd.setCursor(0, 1);
// If currently in error state
if (reflowState == REFLOW_STATE_ERROR)
{
// Thermocouple error (open, shorted)
lcd.print(F("TC Error"));
}
else
{
// Display current temperature
lcd.print(input);
#if ARDUINO >= 100
// Display degree Celsius symbol
lcd.write((uint8_t)0);
#else
// Display degree Celsius symbol
lcd.print(0, BYTE);
#endif
lcd.print("C ");
}
#elif VERSION == 2
oled.clearDisplay();
oled.setTextSize(2);
oled.setCursor(0, 0);
oled.print(lcdMessagesReflowStatus[reflowState]);
oled.setTextSize(1);
oled.setCursor(115, 0);
if (reflowProfile == REFLOW_PROFILE_LEADFREE)
{
oled.print(F("LF"));
}
else
{
oled.print(F("PB"));
}
// Temperature markers
oled.setCursor(0, 18);
oled.print(F("250"));
oled.setCursor(0, 36);
oled.print(F("150"));
oled.setCursor(0, 54);
oled.print(F("50"));
// Draw temperature and time axis
oled.drawLine(18, 18, 18, 63, WHITE);
oled.drawLine(18, 63, 127, 63, WHITE);
oled.setCursor(115, 0);
// If currently in error state
if (reflowState == REFLOW_STATE_ERROR)
{
oled.setCursor(80, 9);
oled.print(F("TC Error"));
}
else
{
// Right align temperature reading
if (input < 10) oled.setCursor(91, 9);
else if (input < 100) oled.setCursor(85,9);
else oled.setCursor(80, 9);
// Display current temperature
oled.print(input);
oled.print((char)247);
oled.print(F("C"));
}
if (reflowStatus == REFLOW_STATUS_ON)
{
// We are updating the display faster than sensor reading
if (timerSeconds > timerUpdate)
{
// Store temperature reading every 3 s
if ((timerSeconds % 3) == 0)
{
timerUpdate = timerSeconds;
unsigned char averageReading = map(input, 0, 250, 63, 19);
if (x < (SCREEN_WIDTH - X_AXIS_START))
{
temperature[x++] = averageReading;
}
}
}
}
unsigned char timeAxis;
for (timeAxis = 0; timeAxis < x; timeAxis++)
{
oled.drawPixel(timeAxis + X_AXIS_START, temperature[timeAxis], WHITE);
}
// Update screen
oled.display();
#endif
}
// Reflow oven controller state machine
switch (reflowState)
{
case REFLOW_STATE_IDLE:
// If oven temperature is still above room temperature
if (input >= TEMPERATURE_ROOM)
{
reflowState = REFLOW_STATE_TOO_HOT;
}
else
{
// If switch is pressed to start reflow process
if (switchStatus == SWITCH_1)
{
// Send header for CSV file
Serial.println(F("Time,Setpoint,Input,Output"));
// Intialize seconds timer for serial debug information
timerSeconds = 0;
#if VERSION == 2
// Initialize reflow plot update timer
timerUpdate = 0;
for (x = 0; x < (SCREEN_WIDTH - X_AXIS_START); x++)
{
temperature[x] = 0;
}
// Initialize index for average temperature array used for reflow plot
x = 0;
#endif
// Initialize PID control window starting time
windowStartTime = millis();
// Ramp up to minimum soaking temperature
setpoint = TEMPERATURE_SOAK_MIN;
// Load profile specific constant
if (reflowProfile == REFLOW_PROFILE_LEADFREE)
{
soakTemperatureMax = TEMPERATURE_SOAK_MAX_LF;
reflowTemperatureMax = TEMPERATURE_REFLOW_MAX_LF;
soakMicroPeriod = SOAK_MICRO_PERIOD_LF;
}
else
{
soakTemperatureMax = TEMPERATURE_SOAK_MAX_PB;
reflowTemperatureMax = TEMPERATURE_REFLOW_MAX_PB;
soakMicroPeriod = SOAK_MICRO_PERIOD_PB;
}
// Tell the PID to range between 0 and the full window size
reflowOvenPID.SetOutputLimits(0, windowSize);
reflowOvenPID.SetSampleTime(PID_SAMPLE_TIME);
// Turn the PID on
reflowOvenPID.SetMode(AUTOMATIC);
// Proceed to preheat stage
reflowState = REFLOW_STATE_PREHEAT;
}
}
break;
case REFLOW_STATE_PREHEAT:
reflowStatus = REFLOW_STATUS_ON;
// If minimum soak temperature is achieve
if (input >= TEMPERATURE_SOAK_MIN)
{
// Chop soaking period into smaller sub-period
timerSoak = millis() + soakMicroPeriod;
// Set less agressive PID parameters for soaking ramp
reflowOvenPID.SetTunings(PID_KP_SOAK, PID_KI_SOAK, PID_KD_SOAK);
// Ramp up to first section of soaking temperature
setpoint = TEMPERATURE_SOAK_MIN + SOAK_TEMPERATURE_STEP;
// Proceed to soaking state
reflowState = REFLOW_STATE_SOAK;
}
break;
case REFLOW_STATE_SOAK:
// If micro soak temperature is achieved
if (millis() > timerSoak)
{
timerSoak = millis() + soakMicroPeriod;
// Increment micro setpoint
setpoint += SOAK_TEMPERATURE_STEP;
if (setpoint > soakTemperatureMax)
{
// Set agressive PID parameters for reflow ramp
reflowOvenPID.SetTunings(PID_KP_REFLOW, PID_KI_REFLOW, PID_KD_REFLOW);
// Ramp up to first section of soaking temperature
setpoint = reflowTemperatureMax;
// Proceed to reflowing state
reflowState = REFLOW_STATE_REFLOW;
}
}
break;
case REFLOW_STATE_REFLOW:
// We need to avoid hovering at peak temperature for too long
// Crude method that works like a charm and safe for the components
if (input >= (reflowTemperatureMax - 5))
{
// Set PID parameters for cooling ramp
reflowOvenPID.SetTunings(PID_KP_REFLOW, PID_KI_REFLOW, PID_KD_REFLOW);
// Ramp down to minimum cooling temperature
setpoint = TEMPERATURE_COOL_MIN;
// Proceed to cooling state
reflowState = REFLOW_STATE_COOL;
}
break;
case REFLOW_STATE_COOL:
// If minimum cool temperature is achieve
if (input <= TEMPERATURE_COOL_MIN)
{
// Retrieve current time for buzzer usage
buzzerPeriod = millis() + 1000;
// Turn on buzzer to indicate completion
//digitalWrite(buzzerPin, HIGH);
tone_finish();
// Turn off reflow process
reflowStatus = REFLOW_STATUS_OFF;
// Proceed to reflow Completion state
reflowState = REFLOW_STATE_COMPLETE;
}
break;
case REFLOW_STATE_COMPLETE:
if (millis() > buzzerPeriod)
{
// Turn off buzzer
//digitalWrite(buzzerPin, LOW);
tone_finish();
// Reflow process ended
reflowState = REFLOW_STATE_IDLE;
}
break;
case REFLOW_STATE_TOO_HOT:
// If oven temperature drops below room temperature
if (input < TEMPERATURE_ROOM)
{
// Ready to reflow
reflowState = REFLOW_STATE_IDLE;
}
break;
case REFLOW_STATE_ERROR:
// Check for thermocouple fault
/*
fault = thermocouple.readFault();
// If thermocouple problem is still present
if ((fault & MAX31856_FAULT_CJRANGE) ||
(fault & MAX31856_FAULT_TCRANGE) ||
(fault & MAX31856_FAULT_CJHIGH) ||
(fault & MAX31856_FAULT_CJLOW) ||
(fault & MAX31856_FAULT_TCHIGH) ||
(fault & MAX31856_FAULT_TCLOW) ||
(fault & MAX31856_FAULT_OVUV) ||
(fault & MAX31856_FAULT_OPEN))
{
// Wait until thermocouple wire is connected
reflowState = REFLOW_STATE_ERROR;
}*/
if (isnan(input)) {
reflowState = REFLOW_STATE_ERROR;
}
else
{
// Clear to perform reflow process
reflowState = REFLOW_STATE_IDLE;
}
break;
}
// If switch 1 is pressed
if (switchStatus == SWITCH_1)