Add support for using multiple memory slots in rmt setup (#3568)

* Add support for using multiple memory slots in rmt setup

* Fix a crash when stopping an RMT receiver

* Add missing docs to the mkdocs

components/modules/rmt.c

@@ -49,7 +49,7 @@ static int configure_channel(lua_State *L, rmt_config_t *config, rmt_mode_t mode
   lua_setmetatable(L, -2);
 
   // We have allocated the channel -- must free it if the rest of this method fails
-  int channel = platform_rmt_allocate(1, mode);
+  int channel = platform_rmt_allocate(config->mem_block_num, mode);
 
   if (channel < 0) {
     return luaL_error(L, "no spare RMT channel");
@@ -66,7 +66,7 @@ static int configure_channel(lua_State *L, rmt_config_t *config, rmt_mode_t mode
     return luaL_error(L, "Failed to configure RMT");
   }
 
-  rc = rmt_driver_install(config->channel, 1000, 0);
+  rc = rmt_driver_install(config->channel, config->mem_block_num * 600, 0);
   if (rc) {
     platform_rmt_release(config->channel);
     return luaL_error(L, "Failed to install RMT driver");
@@ -112,6 +112,13 @@ static int lrmt_txsetup(lua_State *L) {
       config.flags |= RMT_CHANNEL_FLAGS_INVERT_SIG;
     }
     lua_pop(L, 1);
+
+    lua_getfield(L, 3, "slots");
+    int slots = lua_tointeger(L, -1);
+    if (slots > 0 && slots <= 8) {
+      config.mem_block_num = slots;
+    }
+    lua_pop(L, 1);
   }
 
   configure_channel(L, &config, RMT_MODE_TX);
@@ -155,6 +162,13 @@ static int lrmt_rxsetup(lua_State *L) {
       config.rx_config.idle_threshold = threshold;
     }
     lua_pop(L, 1);
+
+    lua_getfield(L, 3, "slots");
+    int slots = lua_tointeger(L, -1);
+    if (slots > 0 && slots <= 8) {
+      config.mem_block_num = slots;
+    }
+    lua_pop(L, 1);
   }
 
   configure_channel(L, &config, RMT_MODE_RX);
@@ -202,6 +216,7 @@ static void handle_receive(void *param) {
       vRingbufferReturnItem(rb, (void *) items);
     }
   }
+  rmt_rx_stop(p->channel);
 
   p->dont_call = true;
   task_post_high(cb_task_id, (task_param_t) p);

docs/modules/rmt.md

@@ -40,6 +40,7 @@ This optional table consists of a number of keys that control various aspects of
 - `carrier_hz` specifies that the signal is to modulate the carrier at the specified frequency. This is useful for IR transmissions.
 - `carrier_duty` specifies the duty cycle of the carrier. Defaults to 50%
 - `idle_level` specifies what value to send when the transmission completes.
+- `slots` If specified, then the number of memory slots used for transmission. 1 slot = 64 pulses (i.e. high and low widths). Total slots in the system are 8 (on the ESP32). Slots cannot be shared.
 
 ## rmt.rxsetup(gpio, bitrate, options)
 
@@ -71,6 +72,7 @@ This optional table consists of a number of keys that control various aspects of
 - `invert` if true, then the input is inverted.
 - `filter_ticks` If specified, then any pulse shorter than this will be ignored. This is in units of the bit time.
 - `idle_threshold` If specified, then any level longer than this will set the receiver as idle. The default is 65535 bit times.
+- `slots` If specified, then the number of memory slots used for reception. 1 slot = 64 pulses (i.e. high and low widths). Total slots in the system are 8 (on the ESP32). Slots cannot be shared.
 
 
 ## channel:on(event, callback)

mkdocs.yml

@@ -47,6 +47,7 @@ pages:
       - 'dac': 'modules/dac.md'
       - 'dht': 'modules/dht.md'
       - 'encoder': 'modules/encoder.md'
+      - 'eromfs': 'modules/eromfs.md'
       - 'eth': 'modules/eth.md'
       - 'file': 'modules/file.md'
       - 'gpio': 'modules/gpio.md'
@@ -64,6 +65,7 @@ pages:
       - 'pipe':         'modules/pipe.md'
       - 'pulsecnt': 'modules/pulsecnt.md'
       - 'qrcodegen': 'modules/qrcodegen.md'
+      - 'rmt': 'modules/rmt.md'
       - 'sdmmc': 'modules/sdmmc.md'
       - 'sigma delta': 'modules/sigma-delta.md'
       - 'sjson': 'modules/sjson.md'