IR transmit example (#180)

* DWT-based microsecond delay

* simple ir app (work only with NEC protocol and predefined address - command)

* remove space from file name, add delay_us_init_DWT header

* float-based delay us

* init tim2 by CubeMX

* fix simple pwm functions

* simple pwm timer based ir nec protocol

* ir gui test app

Co-authored-by: aanper <mail@s3f.ru>

applications/irda/irda_protocols.h

@@ -0,0 +1,16 @@
+#pragma once
+
+// our tx pin is TIM2_CH4
+extern TIM_HandleTypeDef htim2;
+
+#define RC5_CARRIER_FREQUENCY 36000
+#define RC5_DUTY_CYCLE 0.33
+
+#define RC6_CARRIER_FREQUENCY 36000
+#define RC6_DUTY_CYCLE 0.33
+
+#define NEC_CARRIER_FREQUENCY 38000
+#define NEC_DUTY_CYCLE 0.33
+
+#define SIRC_CARRIER_FREQUENCY 40000
+#define SIRC_DUTY_CYCLE 0.5