Add PulseIn

5 files changed, 184 insertions, 9 deletions

diff --git a/ports/esp32s2/background.c b/ports/esp32s2/background.c
index 40ce9ecfd..3160d9974 100644
--- a/ports/esp32s2/background.c
+++ b/ports/esp32s2/background.c
@@ -35,10 +35,17 @@
 #include "shared-module/displayio/__init__.h"
 #endif
 
+#if CIRCUITPY_PULSEIO
+#include "common-hal/pulseio/PulseIn.h"
+#endif
+
 
 void port_background_task(void) {
     // Zero delay in case FreeRTOS wants to switch to something else.
     vTaskDelay(0);
+    #if CIRCUITPY_PULSEIO
+    pulsein_background();
+    #endif
 }
 
 void port_start_background_task(void) {}
diff --git a/ports/esp32s2/common-hal/pulseio/PulseIn.c b/ports/esp32s2/common-hal/pulseio/PulseIn.c
index 65fc6631d..5209c51ca 100644
--- a/ports/esp32s2/common-hal/pulseio/PulseIn.c
+++ b/ports/esp32s2/common-hal/pulseio/PulseIn.c
@@ -27,49 +27,208 @@
 #include "common-hal/pulseio/PulseIn.h"
 #include "py/runtime.h"
 
-// STATIC void pulsein_handler(uint8_t num) {
-// }
+STATIC uint8_t refcount = 0;
+STATIC pulseio_pulsein_obj_t * handles[RMT_CHANNEL_MAX];
+
+// Requires rmt.c void esp32s2_peripherals_reset_all(void) to reset
+
+STATIC void update_internal_buffer(pulseio_pulsein_obj_t* self) {
+    //mp_printf(&mp_plat_print, "Update internal Buffer\n");
+    uint32_t length = 0;
+    rmt_item32_t *items = (rmt_item32_t *) xRingbufferReceive(self->buf_handle, &length, 0);
+    if (items) {
+        length /= 4;
+        //mp_printf(&mp_plat_print, "Length%d\n",length);
+        // TODO: If the size of the recieve is larger than the buffer, reset it?
+
+        for (size_t i=0; i < length; i++) {
+            //mp_printf(&mp_plat_print, "Item d0:%d, l0:%d, d1:%d, l1:%d\n",(items[i].duration0 * 3),
+            //          items[i].level0,(items[i].duration1 * 3),items[i].level1);
+            uint16_t pos = (self->start + self->len) % self->maxlen;
+            self->buffer[pos] = items[i].duration0 * 3;
+            // Check if second item exists before incrementing
+            if (items[i].duration1) {
+                self->buffer[pos+1] = items[i].duration1 * 3;
+                if (self->len < (self->maxlen - 1)) {
+                    self->len += 2;
+                } else {
+                    self->start += 2;
+                }
+            } else {
+                if (self->len < self->maxlen) {
+                    self->len++;
+                } else {
+                    self->start++;
+                }
+            }
+        }
+        vRingbufferReturnItem(self->buf_handle, (void *) items);
+    }
+}
+
+// We can't access the RMT interrupt, so we need a global service to prevent
+// the ringbuffer from overflowing and crashing the peripheral
+void pulsein_background(void) {
+    //mp_printf(&mp_plat_print, "BG Task!\n");
+    for (size_t i = 0; i < RMT_CHANNEL_MAX; i++) {
+        if (handles[i]) {
+            //mp_printf(&mp_plat_print, "Located viable handle:%d\n",i);
+            update_internal_buffer(handles[i]);
+            UBaseType_t items_waiting;
+            vRingbufferGetInfo(handles[i]->buf_handle, NULL, NULL, NULL, NULL, &items_waiting);
+            //mp_printf(&mp_plat_print, "items waiting:%d\n",items_waiting);
+            // if (items_waiting > handles[i]->maxlen) {
+            //     mp_printf(&mp_plat_print, "Overage!\n");
+            //     mp_printf(&mp_plat_print, "Items waiting detected:%d\n", items_waiting);
+            //     update_internal_buffer(handles[i]);
+            // }
+        }
+    }
+}
 
 void pulsein_reset(void) {
+    mp_printf(&mp_plat_print, "Pulsein Reset called\n");
+    for (size_t i = 0; i < RMT_CHANNEL_MAX; i++) {
+        handles[i] = NULL;
+    }
+    supervisor_disable_tick();
+    refcount = 0;
 }
 
 void common_hal_pulseio_pulsein_construct(pulseio_pulsein_obj_t* self, const mcu_pin_obj_t* pin,
                                              uint16_t maxlen, bool idle_state) {
-    mp_raise_NotImplementedError(translate("PulseIn not supported on this chip"));
+    self->buffer = (uint16_t *) m_malloc(maxlen * sizeof(uint16_t), false);
+    if (self->buffer == NULL) {
+        mp_raise_msg_varg(&mp_type_MemoryError, translate("Failed to allocate RX buffer of %d bytes"), maxlen * sizeof(uint16_t));
+    }
+    self->pin = pin;
+    self->maxlen = maxlen;
+    // self->idle_state = idle_state;
+    self->start = 0;
+    self->len = 0;
+    // self->first_edge = true;
+    self->paused = false;
+    // self->last_overflow = 0;
+    // self->last_count = 0;
+
+    rmt_channel_t channel = esp32s2_peripherals_find_and_reserve_rmt();
+    mp_printf(&mp_plat_print, "Selected Channel:%d!\n",channel);
+
+    // Configure Channel
+    rmt_config_t config = RMT_DEFAULT_CONFIG_RX(pin->number, channel);
+    config.rx_config.filter_en = true;
+    config.rx_config.idle_threshold = 30000;
+    config.clk_div = 240;
+
+    rmt_config(&config);
+    size_t len = 1000; //TODO: pick a reasonable number for this?
+    // size_t len = maxlen * 4;
+    rmt_driver_install(channel, len, 0);
+
+    self->channel = channel;
+
+    // Store handle for background updates
+    handles[channel] = self;
+
+    rmt_get_ringbuf_handle(channel, &(self->buf_handle));
+    rmt_rx_start(channel, true);
+
+    supervisor_enable_tick();
+    refcount++;
 }
 
 bool common_hal_pulseio_pulsein_deinited(pulseio_pulsein_obj_t* self) {
-    return false;
+    return handles[self->channel] ? true : false;
 }
 
 void common_hal_pulseio_pulsein_deinit(pulseio_pulsein_obj_t* self) {
+    handles[self->channel] = NULL;
+    esp32s2_peripherals_free_rmt(self->channel);
+    reset_pin_number(self->pin);
+    refcount--;
+    if (refcount == 0) {
+        supervisor_disable_tick();
+    }
 }
 
 void common_hal_pulseio_pulsein_pause(pulseio_pulsein_obj_t* self) {
+    self->paused = true;
+    rmt_rx_stop();
 }
 
 void common_hal_pulseio_pulsein_resume(pulseio_pulsein_obj_t* self, uint16_t trigger_duration) {
+    // Make sure we're paused.
+    if ( !self->paused ) {
+        common_hal_pulseio_pulsein_pause(self);
+    }
+
+    self->paused = false;
+    rmt_rx_start();
 }
 
 void common_hal_pulseio_pulsein_clear(pulseio_pulsein_obj_t* self) {
+    self->start = 0;
+    self->len = 0;
 }
 
 uint16_t common_hal_pulseio_pulsein_get_item(pulseio_pulsein_obj_t* self, int16_t index) {
-    return false;
+    //mp_printf(&mp_plat_print, "Call GetItem\n");
+    update_internal_buffer(self);
+    if (index < 0) {
+        index += self->len;
+    }
+    if (index < 0 || index >= self->len) {
+        mp_raise_IndexError(translate("index out of range"));
+    }
+    uint16_t value = self->buffer[(self->start + index) % self->maxlen];
+    return value;
 }
 
 uint16_t common_hal_pulseio_pulsein_popleft(pulseio_pulsein_obj_t* self) {
-    return false;
+    mp_printf(&mp_plat_print, "Call PopLeft\n");
+    update_internal_buffer(self);
+
+    if (self->len == 0) {
+        mp_raise_IndexError(translate("pop from an empty PulseIn"));
+    }
+
+    uint16_t value = self->buffer[self->start];
+    self->start = (self->start + 1) % self->maxlen;
+    self->len--;
+
+    return value;
+
+
+    // uint32_t length = 0;
+    // rmt_item32_t *items = (rmt_item32_t *) xRingbufferReceive(self->buf_handle, &length, 10);
+    // mp_printf(&mp_plat_print, "Length%d\n",length);
+    // if (items) {
+    //     length /= 4;
+    //     mp_printf(&mp_plat_print, "Length%d\n",length);
+    //     for (size_t i=0; i < length; i++) {
+    //         mp_printf(&mp_plat_print, "Item d0:%d, l0:%d, d1:%d, l1:%d\n",(items[i].duration0 * 3),
+    //                   items[i].level0,(items[i].duration1 * 3),items[i].level1);
+    //     }
+    //     vRingbufferReturnItem(self->buf_handle, (void *) items);
+    // }
+    // // while(items) {
+    // //     mp_printf(&mp_plat_print, "Length%d",length);
+    // //     mp_printf(&mp_plat_print, "Item val0:%d, val1:%d, val:%d",items->duration0,
+    // //                     items->duration1,items->val);
+    // //     vRingbufferReturnItem(self->buf_handle, (void *) items);
+    // //     items = (rmt_item32_t *) xRingbufferReceive(self->buf_handle, &length, 1);
+    // // }
+    // return items ? items[0].duration0 : false;
 }
 
 uint16_t common_hal_pulseio_pulsein_get_maxlen(pulseio_pulsein_obj_t* self) {
-    return false;
+    return self->maxlen;
 }
 
 bool common_hal_pulseio_pulsein_get_paused(pulseio_pulsein_obj_t* self) {
-    return false;
+    return self->paused;
 }
 
 uint16_t common_hal_pulseio_pulsein_get_len(pulseio_pulsein_obj_t* self) {
-    return false;
+    return self->len;
 }
diff --git a/ports/esp32s2/common-hal/pulseio/PulseIn.h b/ports/esp32s2/common-hal/pulseio/PulseIn.h
index b317c516c..1ac47cfe1 100644
--- a/ports/esp32s2/common-hal/pulseio/PulseIn.h
+++ b/ports/esp32s2/common-hal/pulseio/PulseIn.h
@@ -30,13 +30,18 @@
 #include "common-hal/microcontroller/Pin.h"
 
 #include "py/obj.h"
+#include "driver/rmt.h"
+#include "rmt.h"
 
 typedef struct {
     mp_obj_base_t base;
 
     const mcu_pin_obj_t* pin;
+    rmt_channel_t channel;
     bool idle_state;
     bool paused;
+
+    RingbufHandle_t buf_handle;
     volatile bool first_edge;
 
     uint16_t* buffer;
@@ -49,5 +54,6 @@ typedef struct {
 } pulseio_pulsein_obj_t;
 
 void pulsein_reset(void);
+void pulsein_background(void);
 
 #endif // MICROPY_INCLUDED_ESP32S2_COMMON_HAL_PULSEIO_PULSEIN_H
diff --git a/ports/esp32s2/peripherals/rmt.c b/ports/esp32s2/peripherals/rmt.c
index 16605edf5..c3a063eec 100644
--- a/ports/esp32s2/peripherals/rmt.c
+++ b/ports/esp32s2/peripherals/rmt.c
@@ -30,6 +30,7 @@
 bool rmt_reserved_channels[RMT_CHANNEL_MAX];
 
 void esp32s2_peripherals_rmt_reset(void) {
+    mp_printf(&mp_plat_print, "RMT Reset called\n");
     for (size_t i = 0; i < RMT_CHANNEL_MAX; i++) {
         if (rmt_reserved_channels[i]) {
             esp32s2_peripherals_free_rmt(i);
diff --git a/ports/esp32s2/supervisor/port.c b/ports/esp32s2/supervisor/port.c
index d287079b7..46590b551 100644
--- a/ports/esp32s2/supervisor/port.c
+++ b/ports/esp32s2/supervisor/port.c
@@ -39,6 +39,7 @@
 #include "common-hal/busio/SPI.h"
 #include "common-hal/busio/UART.h"
 #include "common-hal/pulseio/PWMOut.h"
+#include "common-hal/pulseio/PulseIn.h"
 #include "supervisor/memory.h"
 #include "supervisor/shared/tick.h"
 
@@ -70,6 +71,7 @@ void reset_port(void) {
 #if CIRCUITPY_PULSEIO
     esp32s2_peripherals_rmt_reset();
     pwmout_reset();
+    pulsein_reset();
 #endif
 #if CIRCUITPY_BUSIO
     i2c_reset();