ARM: implement heater-arm.c partially.

Currently at a fixed frequency of 1 kHz and with a fixed duty
cycle of 10%, but PWM does work.

As it turns out, PIO0_11 is not usable for PWM, because its timer
is already in use for the Step timer, and had to be disabled for
Gen7-ARM.

Test: define a heater in board.gen7-arm.h and a square signal
of 1 kHz with 10% duty cycle should appear on the heater pin.

Makefile-ARM

@@ -100,10 +100,10 @@ TARGET = $(PROGRAM).hex
 SOURCES  = mendel.c cpu.c serial.c sermsg.c sersendf.c delay.c
 SOURCES += gcode_parse.c gcode_process.c pinio.c timer.c clock.c
 SOURCES += dda_queue.c dda_maths.c dda_kinematics.c dda.c dda_lookahead.c
-SOURCES += analog.c temp.c
+SOURCES += analog.c temp.c heater.c
 # Sources left:
 # home.c crc.c intercom.c debug.c spi.c usb_serial.c
-# graycode.c pff.c watchdog.c heater.c pff_diskio.c
+# graycode.c pff.c watchdog.c pff_diskio.c
 
 ifeq ($(MCU), lpc1114)
   SOURCES += cmsis-system_lpc11xx.c

arduino_lpc1114.h

@@ -95,6 +95,7 @@
 #define PIO0_1_PIN      1
 #define PIO0_1_PORT     LPC_GPIO0
 #define PIO0_1_OUTPUT   0x00
+// Timer pin CT32B0_MAT2, but timer used for Step interrupt.
 
 #define PIO0_2_CMSIS    PIO0_2
 #define PIO0_2_PIN      2
@@ -130,22 +131,32 @@
 #define PIO0_8_PIN      8
 #define PIO0_8_PORT     LPC_GPIO0
 #define PIO0_8_OUTPUT   0x00
+#define PIO0_8_TIMER    LPC_TMR16B0
+#define PIO0_8_MATCH    1
+#define PIO0_8_PWM      (0x02 << 0)
 
 #define PIO0_9_CMSIS    PIO0_9
 #define PIO0_9_PIN      9
 #define PIO0_9_PORT     LPC_GPIO0
 #define PIO0_9_OUTPUT   0x00
+#define PIO0_9_TIMER    LPC_TMR16B0
+#define PIO0_9_MATCH    1
+#define PIO0_9_PWM      (0x02 << 0)
 
 #define PIO0_10_CMSIS   SWCLK_PIO0_10
 #define PIO0_10_PIN     10
 #define PIO0_10_PORT    LPC_GPIO0
 #define PIO0_10_OUTPUT  (0x01 << 0)
+#define PIO0_10_TIMER   LPC_TMR16B0
+#define PIO0_10_MATCH   2
+#define PIO0_10_PWM     (0x03 << 0)
 
 #define PIO0_11_CMSIS   R_PIO0_11
 #define PIO0_11_PIN     11
 #define PIO0_11_PORT    LPC_GPIO0
 #define PIO0_11_OUTPUT  ((0x01 << 0) | (0x01 << 7))
 #define PIO0_11_ADC     0
+// Timer pin CT32B0_MAT3, but timer used for Step interrupt.
 
 #define PIO1_0_CMSIS    R_PIO1_0
 #define PIO1_0_PIN      0
@@ -158,24 +169,34 @@
 #define PIO1_1_PORT     LPC_GPIO1
 #define PIO1_1_OUTPUT   ((0x01 << 0) | (0x01 << 7))
 #define PIO1_1_ADC      2
+#define PIO1_1_TIMER    LPC_TMR32B1
+#define PIO1_1_MATCH    0
+#define PIO1_1_PWM      (0x03 << 0)
 
 #define PIO1_2_CMSIS    R_PIO1_2
 #define PIO1_2_PIN      2
 #define PIO1_2_PORT     LPC_GPIO1
 #define PIO1_2_OUTPUT   ((0x01 << 0) | (0x01 << 7))
 #define PIO1_2_ADC      3
+#define PIO1_2_TIMER    LPC_TMR32B1
+#define PIO1_2_MATCH    1
+#define PIO1_2_PWM      (0x03 << 0)
 
 #define PIO1_3_CMSIS    SWDIO_PIO1_3
 #define PIO1_3_PIN      3
 #define PIO1_3_PORT     LPC_GPIO1
 #define PIO1_3_OUTPUT   ((0x01 << 0) | (0x01 << 7))
 #define PIO1_3_ADC      4
+#define PIO1_3_TIMER    LPC_TMR32B1
+#define PIO1_3_MATCH    2
+#define PIO1_3_PWM      (0x03 << 0)
 
 #define PIO1_4_CMSIS    PIO1_4
 #define PIO1_4_PIN      4
 #define PIO1_4_PORT     LPC_GPIO1
 #define PIO1_4_OUTPUT   (0x01 << 7)
 #define PIO1_4_ADC      5
+// Timer pin CT32B1_MAT3, but match used for PWM reset.
 
 #define PIO1_5_CMSIS    PIO1_5
 #define PIO1_5_PIN      5
@@ -186,11 +207,13 @@
 #define PIO1_6_PIN      6
 #define PIO1_6_PORT     LPC_GPIO1
 #define PIO1_6_OUTPUT   0x00
+// Timer pin CT32B0_MAT0, but timer used for Step interrupt.
 
 #define PIO1_7_CMSIS    PIO1_7
 #define PIO1_7_PIN      7
 #define PIO1_7_PORT     LPC_GPIO1
 #define PIO1_7_OUTPUT   0x00
+// Timer pin CT32B0_MAT1, but timer used for Step interrupt.
 
 #define PIO1_8_CMSIS    PIO1_8
 #define PIO1_8_PIN      8
@@ -201,3 +224,6 @@
 #define PIO1_9_PIN      9
 #define PIO1_9_PORT     LPC_GPIO1
 #define PIO1_9_OUTPUT   0x00
+#define PIO1_9_TIMER    LPC_TMR16B1
+#define PIO1_9_MATCH    0
+#define PIO1_9_PWM      (0x01 << 0)

clock.c

@@ -71,11 +71,8 @@ void clock_tick(void) {
 	called from clock_10ms(), do not call directly
 */
 static void clock_250ms(void) {
-  #ifndef __ARMEL_NOTYET__
+
   if (heaters_all_zero()) {
-  #else
-  if (1) {
-  #endif /* __ARMEL_NOTYET__, ! __ARMEL_NOTYET__ */
 		if (psu_timeout > (30 * 4)) {
 			power_off();
 		}

config/board.gen7-arm.h

@@ -163,8 +163,8 @@
 */
 //DEFINE_TEMP_SENSORS_START
 //                 name      type           pin    additional
-DEFINE_TEMP_SENSOR(extruder, TT_THERMISTOR, PIO1_1,THERMISTOR_EXTRUDER)
+DEFINE_TEMP_SENSOR(extruder, TT_THERMISTOR, PIO1_0,THERMISTOR_EXTRUDER)
-DEFINE_TEMP_SENSOR(bed,      TT_THERMISTOR, PIO1_0,THERMISTOR_BED)
+//DEFINE_TEMP_SENSOR(bed,      TT_THERMISTOR, PIO1_1,THERMISTOR_BED)
 
 // Beta algorithm      r0      beta  r2    vadc
 // Steinhart-Hart      rp      t0    r0      t1    r1      t2    r2
@@ -220,11 +220,11 @@ DEFINE_TEMP_SENSOR(bed,      TT_THERMISTOR, PIO1_0,THERMISTOR_BED)
 */
 //DEFINE_HEATERS_START
 //            name      port   pwm
-DEFINE_HEATER(extruder, PIO0_11, 1)
+DEFINE_HEATER(extruder, PIO0_10, 1)
-DEFINE_HEATER(bed,      PIO0_10, 1)
+//DEFINE_HEATER(bed,      PIO0_11, 1)
 
 #define HEATER_EXTRUDER HEATER_extruder
-#define HEATER_BED HEATER_bed
+//#define HEATER_BED HEATER_bed
 //DEFINE_HEATERS_END
 
 

config_wrapper.h

@@ -42,3 +42,32 @@
            Lookahead disabled.
   #undef LOOKAHEAD
 #endif
+
+/**
+  Silently discard EECONFIG on ARM. Silently to not disturb regression tests.
+
+  TODO:
+
+   - EECONFIG is currently misplaced as a printer property. Move EECONFIG to
+     the board configuration or drop it entirely in favour of PID settings in
+     Configtool.
+
+   - Remove this silent discard in favour of the #error in heater-arm.c.
+*/
+#if defined __ARMEL__ && defined EECONFIG
+  #undef EECONFIG
+#endif
+
+/**
+  Silently discard BANG_BANG on ARM. Silently to not disturb regression tests.
+
+  TODO:
+
+   - BANG_BANG is currently misplaced as a printer property. Move BANG_BANG to
+     the board configuration.
+
+   - Remove this silent discard in favour of the #error in heater-arm.c.
+*/
+#if defined __ARMEL__ && defined BANG_BANG
+  #undef BANG_BANG
+#endif

gcode_process.c

@@ -724,7 +724,6 @@ void process_gcode_command() {
         serial_writechar('\n');
         break;
 
-      #ifndef __ARMEL_NOTYET__
       #ifdef EECONFIG
 			case 130:
 				//? --- M130: heater P factor ---
@@ -787,7 +786,6 @@ void process_gcode_command() {
 				heater_save_settings();
 				break;
       #endif /* EECONFIG */
-      #endif /* __ARMEL_NOTYET__ */
 
       #ifdef DEBUG
 			case 136:
@@ -800,9 +798,7 @@ void process_gcode_command() {
           #else
             next_target.P = 0;
           #endif
-        #ifndef __ARMEL_NOTYET__
 				heater_print(next_target.P);
-        #endif /* __ARMEL_NOTYET__ */
 				break;
       #endif /* DEBUG */
 

heater-arm.c

@@ -0,0 +1,132 @@
+
+/** \file
+  \brief Manage heaters, including PID and PWM, ARM specific part.
+*/
+
+#if defined TEACUP_C_INCLUDE && defined __ARMEL__
+
+/**
+  Test configuration.
+*/
+#ifdef EECONFIG
+  #error EEPROM handling (EECONFIG) not yet supported on ARM.
+#endif
+
+#ifdef BANG_BANG
+  #error BANG_BANG not supported on ARM. You may set PWM frequency of one \
+         or all heater(s) to zero, which gives similar, better behaviour.
+#endif
+
+/** \def PWM_SCALE
+
+  G-code standard (if such a thing exists at all) gives a heater setting
+  range between 0 (off) and 255 (full on), so we let the PWM timers count up
+  to 255. Doing so allows to set the prescaler for these frequencies (all on
+  a 48 MHz CPU clock):
+
+    prescaler     frequency         prescaler     frequency
+
+            0     188.2 kHz                 4      37.6 kHz
+            1      91.1 kHz                 5      31.4 kHz
+            2      62.7 kHz               ...       ...
+            3      47.0 kHz             65535      2.87 Hz
+
+  As one can see, frequency steps are rather coarse on the high end and
+  become finer grained the lower it gets.
+
+  If this range is generally too high for your purposes, you can set PWM_SCALE
+  to multiples of 255 to lower the range. Doubling it to 510 moves the
+  frequency range to 1.4 Hz...91.1 kHz, quadrupling it to 1020 moves the range
+  to 0.7 Hz...46.9 kHz and so on. The highest allowed number is 65535.
+
+  That said, code below calculates the best prescaler value for a configured
+  frequency, so you should bother about PWM_SCALE only of you need frequencies
+  below 3 Hz.
+*/
+#define PWM_SCALE 255
+
+
+/** Initialise heater subsystem.
+
+  Initialise PWM timers, etc. Inspired by pwm.c in LPC1343CodeBase:
+
+    https://github.com/microbuilder/LPC1343CodeBase
+
+  Note that PWM is inversed, pins start at Low by chip design. When the pin's
+  counter is reached, they're set to High. Reaching the timer reset counter is
+  programmed to reset everything and start over. Thus, having both counter
+  matches similar gives a low duty, having the pin counter match zero gives
+  full on.
+
+  For simplicity we reset all timer counters always on Match 3 and always
+  at PWM_SCALE (255 per default), so setting a pin match to PWM_SCALE / 2
+  gives 50% duty, setting it to PWM_SCALE gives full off. This choice disallows
+  using a pin connected to a Match 3, working around this would make code much
+  more complicated (and still not allow to use more than 3 pins per timer).
+
+  On ARM we can define a PWM frequency pretty fine grained, so we take the
+  'pwm' value of DEFINE_HEATER() not only wether to use PWM at all, but also
+  to define the PWM frequency. Float values are allowed.
+
+  If there's more than one pin on a timer, they share the same PWM frequency;
+  the frequency choosen is the one of the pin defined last.
+*/
+void heater_init() {
+  /**
+    Pins on the LPC1114 are usable as following, capture pins not listed:
+
+      pin      timer/match     func for PWM   other uses
+
+      PIO0_1   CT32B0_MAT2     0x2            ---
+      PIO0_8   CT16B0_MAT0     0x2            MISO0
+      PIO0_9   CT16B0_MAT1     0x2            MOSI0
+      PIO0_10  CT16B0_MAT2     0x3            SCK0 (also on PIO0_6)
+      PIO0_11  CT32B0_MAT3     0x3            AD0, Step timer
+      PIO1_1   CT32B1_MAT0     0x3            AD2
+      PIO1_2   CT32B1_MAT1     0x3            AD3
+      PIO1_3   CT32B1_MAT2     0x3            AD4
+      PIO1_4   CT32B1_MAT3     0x2            AD5, PWM reset
+      PIO1_6   CT32B0_MAT0     0x2            RXD, Step timer
+      PIO1_7   CT32B0_MAT1     0x2            TXD, Step timer
+      PIO1_9   CT16B1_MAT0     0x1            ---
+  */
+  if (NUM_HEATERS) {                            // At least one channel in use.
+
+    // For simplicity, turn on all timers, not only the used ones.
+    // TODO: turn on only the used ones. we know pin ## TIMER.
+    LPC_SYSCON->SYSAHBCLKCTRL |= (1 << 7);        // Turn on CT16B0 power.
+    LPC_SYSCON->SYSAHBCLKCTRL |= (1 << 8);        // Turn on CT16B1 power.
+    LPC_SYSCON->SYSAHBCLKCTRL |= (1 << 10);       // Turn on CT32B1 power.
+
+    // Auto-generate pin setup.
+    #undef DEFINE_HEATER
+    #define DEFINE_HEATER(name, pin, pwm) \
+      LPC_IOCON->pin ## _CMSIS = pin ## _PWM;     /* Connect to timer.   */ \
+      /*pin ## _TIMER->IR  = 0; ( = reset value)     No interrupts.      */ \
+      pin ## _TIMER->TCR   = (1 << 0);            /* Enable counter.     */ \
+      /* TODO: set PWM frequency here according to configuration. */        \
+      /* TODO: check wether configured freq. is within range (1..65536). */ \
+      pin ## _TIMER->PR    =                      /* Prescaler to        */ \
+          F_CPU / PWM_SCALE / 1000 - 1;           /*   1000 Hz.          */ \
+      pin ## _TIMER->MCR   = (1 << 10);           /* Reset on Match 3.   */ \
+      /* PWM_SCALE - 1, so match = 255 is full off. */                      \
+      pin ## _TIMER->MR[3] = PWM_SCALE - 1;       /* Match 3 at 254.     */ \
+      /* TODO: Heaters should start at zero, of course. 10% is as demo. */  \
+      pin ## _TIMER->MR[pin ## _MATCH] =          /* Match pin = duty.   */ \
+          (PWM_SCALE * 0.9);                                                \
+      /*pin ## _TIMER->CCR = 0; ( = reset value)     No pin capture.     */ \
+      pin ## _TIMER->EMR |= ((1 << pin ## _MATCH) /* Connect to pin.     */ \
+          | (0x03 << ((pin ## _MATCH * 2) + 4))); /* Toggle pin on match.*/ \
+      /*pin ## _TIMER->CTCR = 0; ( = reset value)    Timer mode.         */ \
+      pin ## _TIMER->PWMC |= ((1 << 3)            /* 3 to PWM mode.      */ \
+          | (1 << pin ## _MATCH));                /* Pin to PWM mode.    */
+    #include "config_wrapper.h"
+    #undef DEFINE_HEATER
+  } /* NUM_HEATERS */
+
+#if 0
+  pid_init(i);
+#endif /* 0 */
+}
+
+#endif /* defined TEACUP_C_INCLUDE && defined __ARMEL__ */

heater.c

@@ -7,7 +7,7 @@
 
 #define TEACUP_C_INCLUDE
 #include "heater-avr.c"
-//#include "heater-arm.c"
+#include "heater-arm.c"
 #undef TEACUP_C_INCLUDE
 
 #include	<stdlib.h>

mendel.c

@@ -38,8 +38,8 @@
 #ifndef __ARMEL_NOTYET__
 #include	"watchdog.h"
 #include	"debug.h"
-#include	"heater.h"
 #endif /* __ARMEL_NOTYET__ */
+#include	"heater.h"
 #include	"analog.h"
 #include	"pinio.h"
 #include	"clock.h"
@@ -97,10 +97,7 @@ void init(void) {
 	// set up timers
 	timer_init();
 
-  #ifndef __ARMEL_NOTYET__
-	// read PID settings from EEPROM
 	heater_init();
-  #endif /* __ARMEL_NOTYET__ */
 
 	// set up dda
 	dda_init();