Add PulseOut

ports/esp32s2/common-hal/pulseio/PulseOut.c

@@ -29,32 +29,52 @@
 #include "shared-bindings/pulseio/PWMOut.h"
 #include "py/runtime.h"
 
-// STATIC void turn_on(pulseio_pulseout_obj_t *pulseout) {
+// Requires rmt.c void esp32s2_peripherals_reset_all(void) to reset
-// }
-
-// STATIC void turn_off(pulseio_pulseout_obj_t *pulseout) {
-// }
-
-// STATIC void start_timer(void) {
-// }
-
-// STATIC void pulseout_event_handler(void) {
-// }
-
-void pulseout_reset() {
-}
 
 void common_hal_pulseio_pulseout_construct(pulseio_pulseout_obj_t* self,
-                                           const pulseio_pwmout_obj_t* carrier) {
+                                           const mcu_pin_obj_t* pin,
-    mp_raise_NotImplementedError(translate("PulseOut not supported on this chip"));
+                                           uint32_t frequency) {
+
+    rmt_channel_t channel = esp32s2_peripherals_find_and_reserve_rmt();
+
+    // Configure Channel
+    rmt_config_t config = RMT_DEFAULT_CONFIG_TX(pin->number, channel);
+    config.tx_config.carrier_en = true;
+    config.tx_config.carrier_duty_percent = 50;
+    config.tx_config.carrier_freq_hz = frequency;
+    config.clk_div = 80;
+
+    rmt_config(&config);
+    rmt_driver_install(channel, 0, 0);
+
+    self->channel = channel;
 }
 
 bool common_hal_pulseio_pulseout_deinited(pulseio_pulseout_obj_t* self) {
-    return false;
+    return (self->channel == RMT_CHANNEL_MAX);
 }
 
 void common_hal_pulseio_pulseout_deinit(pulseio_pulseout_obj_t* self) {
+    esp32s2_peripherals_free_rmt(self->channel);
+    self->channel = RMT_CHANNEL_MAX;
+
 }
 
 void common_hal_pulseio_pulseout_send(pulseio_pulseout_obj_t* self, uint16_t* pulses, uint16_t length) {
+    rmt_item32_t items[length];
+
+    // Circuitpython allows 16 bit pulse values, while ESP32 only allows 15 bits
+    // Thus, we use entire items for one pulse, rather than switching inside each item
+    for (size_t i = 0; i < length; i++) {
+        // Setting the RMT duration to 0 has undefined behavior, so avoid that pre-emptively.
+        if (pulses[i] == 0) {
+            pulses[i] = 1;
+        }
+        uint32_t level = (i % 2) ? 0 : 1;
+        const rmt_item32_t item = {{{ (pulses[i] & 0x8000 ? 0x7FFF : 1), level, (pulses[i] & 0x7FFF), level}}};
+        items[i] = item;
+    }
+
+    rmt_write_items(self->channel, items, length, true);
+    rmt_wait_tx_done(self->channel, pdMS_TO_TICKS(100));
 }

ports/esp32s2/common-hal/pulseio/PulseOut.h

@@ -29,14 +29,14 @@
 
 #include "common-hal/microcontroller/Pin.h"
 #include "common-hal/pulseio/PWMOut.h"
+#include "driver/rmt.h"
+#include "rmt.h"
 
 #include "py/obj.h"
 
 typedef struct {
     mp_obj_base_t base;
-    pulseio_pwmout_obj_t *pwmout;
+    rmt_channel_t channel;
 } pulseio_pulseout_obj_t;
 
-void pulseout_reset(void);
-
 #endif // MICROPY_INCLUDED_ESP32S2_COMMON_HAL_PULSEIO_PULSEOUT_H

ports/esp32s2/mpconfigport.h

@@ -28,19 +28,20 @@
 #ifndef ESP32S2_MPCONFIGPORT_H__
 #define ESP32S2_MPCONFIGPORT_H__
 
-#define CIRCUITPY_INTERNAL_NVM_SIZE         (0)
+#define CIRCUITPY_INTERNAL_NVM_SIZE     (0)
-#define MICROPY_NLR_THUMB                   (0)
+#define MICROPY_NLR_THUMB               (0)
 
-#define MICROPY_PY_UJSON            (0)
+#define MICROPY_PY_UJSON                (0)
-#define MICROPY_USE_INTERNAL_PRINTF      (0)
+#define MICROPY_USE_INTERNAL_PRINTF     (0)
 
 #include "py/circuitpy_mpconfig.h"
 
+#define CPY_PULSEOUT_USES_DIGITALIO     (1)
 
 #define MICROPY_PORT_ROOT_POINTERS \
 	CIRCUITPY_COMMON_ROOT_POINTERS
-#define MICROPY_NLR_SETJMP                  (1)
+#define MICROPY_NLR_SETJMP              (1)
-#define CIRCUITPY_DEFAULT_STACK_SIZE        0x6000
+#define CIRCUITPY_DEFAULT_STACK_SIZE    (0x6000)
 
 
 #endif  // __INCLUDED_ESP32S2_MPCONFIGPORT_H

ports/esp32s2/peripherals/rmt.c

@@ -29,6 +29,14 @@
 
 bool rmt_reserved_channels[RMT_CHANNEL_MAX];
 
+void esp32s2_peripherals_rmt_reset(void) {
+    for (size_t i = 0; i < RMT_CHANNEL_MAX; i++) {
+        if (rmt_reserved_channels[i]) {
+            esp32s2_peripherals_free_rmt(i);
+        }
+    }
+}
+
 rmt_channel_t esp32s2_peripherals_find_and_reserve_rmt(void) {
     for (size_t i = 0; i < RMT_CHANNEL_MAX; i++) {
         if (!rmt_reserved_channels[i]) {

ports/esp32s2/peripherals/rmt.h

@@ -31,6 +31,7 @@
 #include "driver/rmt.h"
 #include <stdint.h>
 
+void esp32s2_peripherals_rmt_reset(void);
 rmt_channel_t esp32s2_peripherals_find_and_reserve_rmt(void);
 void esp32s2_peripherals_free_rmt(rmt_channel_t chan);
 

ports/esp32s2/supervisor/port.c

@@ -42,6 +42,8 @@
 #include "supervisor/memory.h"
 #include "supervisor/shared/tick.h"
 
+#include "rmt.h"
+
 STATIC esp_timer_handle_t _tick_timer;
 
 void tick_timer_cb(void* arg) {
@@ -66,6 +68,7 @@ void reset_port(void) {
     vTaskDelay(4);
 
 #if CIRCUITPY_PULSEIO
+    esp32s2_peripherals_rmt_reset();
     pwmout_reset();
 #endif
 #if CIRCUITPY_BUSIO

shared-bindings/pulseio/PulseOut.c

@@ -64,19 +64,33 @@
 //|           pulse.send(pulses)"""
 //|         ...
 //|
-STATIC mp_obj_t pulseio_pulseout_make_new(const mp_obj_type_t *type, size_t n_args, const mp_obj_t *args, mp_map_t *kw_args) {
+STATIC mp_obj_t pulseio_pulseout_make_new(const mp_obj_type_t *type, size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
-    mp_arg_check_num(n_args, kw_args, 1, 1, false);
-    mp_obj_t carrier_obj = args[0];
 
-    if (!MP_OBJ_IS_TYPE(carrier_obj, &pulseio_pwmout_type)) {
-        mp_raise_TypeError_varg(translate("Expected a %q"), pulseio_pwmout_type.name);
-    }
-
-    // create Pulse object from the given pin
     pulseio_pulseout_obj_t *self = m_new_obj(pulseio_pulseout_obj_t);
     self->base.type = &pulseio_pulseout_type;
 
+    #ifndef CPY_PULSEOUT_USES_DIGITALIO
+    // Most ports pass a PWMOut
+    mp_arg_check_num(n_args, kw_args, 1, 1, false);
+    mp_obj_t carrier_obj = args[0];
+    if (!MP_OBJ_IS_TYPE(carrier_obj, &pulseio_pwmout_type)) {
+        mp_raise_TypeError_varg(translate("Expected a %q"), pulseio_pwmout_type.name);
+    }
     common_hal_pulseio_pulseout_construct(self, (pulseio_pwmout_obj_t *)MP_OBJ_TO_PTR(carrier_obj));
+    #else
+    // ESP32-S2 Special Case
+    enum { ARG_pin, ARG_frequency};
+    static const mp_arg_t allowed_args[] = {
+        { MP_QSTR_pin, MP_ARG_REQUIRED | MP_ARG_OBJ },
+        { MP_QSTR_frequency, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 38000} },
+    };
+    mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
+    mp_arg_parse_all(n_args, pos_args, kw_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args);
+
+    const mcu_pin_obj_t* pin = validate_obj_is_free_pin(args[ARG_pin].u_obj);
+
+    common_hal_pulseio_pulseout_construct(self, pin, args[ARG_frequency].u_int);
+    #endif
 
     return MP_OBJ_FROM_PTR(self);
 }

shared-bindings/pulseio/PulseOut.h

@@ -33,8 +33,14 @@
 
 extern const mp_obj_type_t pulseio_pulseout_type;
 
+#ifndef CPY_PULSEOUT_USES_DIGITALIO
 extern void common_hal_pulseio_pulseout_construct(pulseio_pulseout_obj_t* self,
     const pulseio_pwmout_obj_t* carrier);
+#else
+extern void common_hal_pulseio_pulseout_construct(pulseio_pulseout_obj_t* self,
+    const mcu_pin_obj_t* pin, uint32_t frequency); 
+#endif
+
 extern void common_hal_pulseio_pulseout_deinit(pulseio_pulseout_obj_t* self);
 extern bool common_hal_pulseio_pulseout_deinited(pulseio_pulseout_obj_t* self);
 extern void common_hal_pulseio_pulseout_send(pulseio_pulseout_obj_t* self,