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Add Duty Cycling to the Heater Bed

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This commit is contained in:
Dabble63 2012-08-11 09:17:47 +03:00
parent 538189cc19
commit 6b45e9f167
2 changed files with 29 additions and 0 deletions
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4
Marlin/Configuration.h
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@ -87,6 +87,10 @@
#define HEATER_2_MAXTEMP 275 #define HEATER_2_MAXTEMP 275
#define BED_MAXTEMP 150 #define BED_MAXTEMP 150
// If your bed has low resistance e.g. .6 ohm and throws the fuse you can duty cycle it to reduce the
// average current. The value should be an integer and the heat bed will be turned on for 1 interval of
// HEATER_BED_DUTY_CYCLE_DIVIDER intervals.
//#define HEATER_BED_DUTY_CYCLE_DIVIDER 4
// PID settings: // PID settings:
// Comment the following line to disable PID and enable bang-bang. // Comment the following line to disable PID and enable bang-bang.

25
Marlin/temperature.cpp
View File

@ -254,6 +254,11 @@ int getHeaterPower(int heater) {
void manage_heater() void manage_heater()
{ {
#ifdef HEATER_BED_DUTY_CYCLE_DIVIDER
static int bed_needs_heating=0;
static int bed_is_on=0;
#endif
#ifdef USE_WATCHDOG #ifdef USE_WATCHDOG
wd_reset(); wd_reset();
#endif #endif
@ -333,12 +338,26 @@ void manage_heater()
} }
#endif #endif
#ifdef HEATER_BED_DUTY_CYCLE_DIVIDER
if (bed_needs_heating){
if (bed_is_on==0)
WRITE(HEATER_BED_PIN,HIGH);
if (bed_is_on==1)
WRITE(HEATER_BED_PIN,LOW);
bed_is_on=(bed_is_on+1) % HEATER_BED_DUTY_CYCLE_DIVIDER;
}
#endif
if(millis() - previous_millis_bed_heater < BED_CHECK_INTERVAL) if(millis() - previous_millis_bed_heater < BED_CHECK_INTERVAL)
return; return;
previous_millis_bed_heater = millis(); previous_millis_bed_heater = millis();
#if TEMP_BED_PIN > -1 #if TEMP_BED_PIN > -1
#ifdef HEATER_BED_DUTY_CYCLE_DIVIDER
bed_needs_heating=0;
#endif
#ifndef BED_LIMIT_SWITCHING #ifndef BED_LIMIT_SWITCHING
// Check if temperature is within the correct range // Check if temperature is within the correct range
if((current_raw_bed > bed_minttemp) && (current_raw_bed < bed_maxttemp)) { if((current_raw_bed > bed_minttemp) && (current_raw_bed < bed_maxttemp)) {
@ -348,6 +367,9 @@ void manage_heater()
} }
else else
{ {
#ifdef HEATER_BED_DUTY_CYCLE_DIVIDER
bed_needs_heating=1;
#endif
WRITE(HEATER_BED_PIN,HIGH); WRITE(HEATER_BED_PIN,HIGH);
} }
} }
@ -364,6 +386,9 @@ void manage_heater()
else else
if(current_raw_bed <= target_bed_low_temp) if(current_raw_bed <= target_bed_low_temp)
{ {
#ifdef HEATER_BED_DUTY_CYCLE_DIVIDER
bed_needs_heating=1;
#endif
WRITE(HEATER_BED_PIN,HIGH); WRITE(HEATER_BED_PIN,HIGH);
} }
} }