Spektrum Satelitte bind code ported from Baseflight

includes support for a hardware bind plug (PB5 pin 41)
Activate via OPTIONS="HARDWARE_BIND_PLUG" during make

src/main/config/config.c

@@ -334,6 +334,7 @@ static void resetConf(void)
     resetTelemetryConfig(&masterConfig.telemetryConfig);
 
     masterConfig.rxConfig.serialrx_provider = 0;
+    masterConfig.rxConfig.spektrum_sat_bind = 0;
     masterConfig.rxConfig.midrc = 1500;
     masterConfig.rxConfig.mincheck = 1100;
     masterConfig.rxConfig.maxcheck = 1900;

src/main/io/serial_cli.c

@@ -271,6 +271,7 @@ const clivalue_t valueTable[] = {
 #endif
 
     { "serialrx_provider",          VAR_UINT8  | MASTER_VALUE,  &masterConfig.rxConfig.serialrx_provider, 0, SERIALRX_PROVIDER_MAX },
+    { "spektrum_sat_bind",          VAR_UINT8  | MASTER_VALUE,  &masterConfig.rxConfig.spektrum_sat_bind, 0, 10 },
 
     { "telemetry_provider",         VAR_UINT8  | MASTER_VALUE,  &masterConfig.telemetryConfig.telemetry_provider, 0, TELEMETRY_PROVIDER_MAX },
     { "telemetry_switch",           VAR_UINT8  | MASTER_VALUE,  &masterConfig.telemetryConfig.telemetry_switch, 0, 1 },

src/main/io/serial_msp.c

@@ -1013,6 +1013,7 @@ static bool processOutCommand(uint8_t cmdMSP)
     case MSP_RX_CONFIG:
         headSerialReply(7);
         serialize8(masterConfig.rxConfig.serialrx_provider);
+        serialize8(masterConfig.rxConfig.spektrum_sat_bind);
         serialize16(masterConfig.rxConfig.maxcheck);
         serialize16(masterConfig.rxConfig.midrc);
         serialize16(masterConfig.rxConfig.mincheck);
@@ -1288,6 +1289,7 @@ static bool processInCommand(void)
     case MSP_SET_RX_CONFIG:
         headSerialReply(0);
         masterConfig.rxConfig.serialrx_provider = read8();
+        masterConfig.rxConfig.spektrum_sat_bind = read8();
         masterConfig.rxConfig.maxcheck = read16();
         masterConfig.rxConfig.midrc = read16();
         masterConfig.rxConfig.mincheck = read16();

src/main/main.c

@@ -105,7 +105,7 @@ void imuInit(void);
 void displayInit(rxConfig_t *intialRxConfig);
 void ledStripInit(ledConfig_t *ledConfigsToUse, hsvColor_t *colorsToUse, failsafe_t* failsafeToUse);
 void loop(void);
-
+void spektrumBind(rxConfig_t *rxConfig);
 
 #ifdef STM32F303xC
 // from system_stm32f30x.c
@@ -150,6 +150,19 @@ void init(void)
 
     systemInit();
 
+    // Spektrum sattelite bind - ported from Baseflight
+    if (feature(FEATURE_RX_MSP)) {
+        switch (masterConfig.rxConfig.serialrx_provider) {
+            case SERIALRX_SPEKTRUM1024:
+            case SERIALRX_SPEKTRUM2048:
+                // Spektrum satellite binding if enabled on startup.
+                // Must be called before that 100ms sleep so that we don't lose satellite's binding window after startup.
+                // The rest of Spektrum initialization will happen later - via spektrumInit()
+                spektrumBind(&masterConfig.rxConfig);
+                break;
+        }
+    }
+
     delay(100);
 
     timerInit();  // timer must be initialized before any channel is allocated

src/main/rx/rx.h

@@ -65,6 +65,7 @@ extern int16_t rcData[MAX_SUPPORTED_RC_CHANNEL_COUNT];       // interval [1000;2
 typedef struct rxConfig_s {
     uint8_t rcmap[MAX_MAPPABLE_RX_INPUTS];  // mapping of radio channels to internal RPYTA+ order
     uint8_t serialrx_provider;              // type of UART-based receiver (0 = spek 10, 1 = spek 11, 2 = sbus). Must be enabled by FEATURE_RX_SERIAL first.
+    uint8_t spektrum_sat_bind;              // number of bind pules for Spektrum sattelite recievers
     uint16_t midrc;                         // Some radios have not a neutral point centered on 1500. can be changed here
     uint16_t mincheck;                      // minimum rc end
     uint16_t maxcheck;                      // maximum rc end

src/main/rx/spektrum.c

@@ -21,12 +21,15 @@
 
 #include "platform.h"
 
+#include "drivers/gpio.h"
 #include "drivers/system.h"
 
 #include "drivers/serial.h"
 #include "drivers/serial_uart.h"
 #include "io/serial.h"
 
+#include "config/config.h"
+
 #include "rx/rx.h"
 #include "rx/spektrum.h"
 
@@ -40,6 +43,8 @@
 
 #define SPEKTRUM_BAUDRATE 115200
 
+#define BKP_SOFTRESET (0x50F7B007)
+
 static uint8_t spek_chan_shift;
 static uint8_t spek_chan_mask;
 static bool rcFrameComplete = false;
@@ -138,3 +143,73 @@ static uint16_t spektrumReadRawRC(rxRuntimeConfig_t *rxRuntimeConfig, uint8_t ch
 
     return data;
 }
+
+uint32_t rccReadBkpDr(void)
+{
+    return *((uint16_t *)BKP_BASE + 0x04) | *((uint16_t *)BKP_BASE + 0x08) << 16;
+}
+
+/* spektrumBind function ported from Baseflight. It's used to bind satellite receiver to TX.
+ * Function must be called immediately after startup so that we don't miss satellite bind window.
+ * Known parameters. Tested with DSMX satellite and DX8 radio. Framerate (11ms or 22ms) must be selected from TX.
+ * 9 = DSMX 11ms / DSMX 22ms
+ * 5 = DSM2 11ms 2048 / DSM2 22ms 1024
+ */
+void spektrumBind(rxConfig_t *rxConfig)
+{
+    int i;
+    gpio_config_t gpio;
+    GPIO_TypeDef *spekBindPort;
+    uint16_t spekBindPin;
+
+#ifdef HARDWARE_BIND_PLUG
+    // Check status of bind plug and exit if not active
+    GPIO_TypeDef *hwBindPort;
+    uint16_t hwBindPin;
+
+    hwBindPort = GPIOB;
+    hwBindPin = Pin_5;
+    gpio.speed = Speed_2MHz;
+    gpio.pin = hwBindPin;
+    gpio.mode = Mode_IPU;
+    gpioInit(hwBindPort, &gpio);
+    if (digitalIn(hwBindPort, hwBindPin))
+        return;
+#endif
+
+    // USART2, PA3
+    spekBindPort = GPIOA;
+    spekBindPin = Pin_3;
+
+    // don't try to bind if: here after soft reset or bind flag is out of range
+    if (rccReadBkpDr() == BKP_SOFTRESET || rxConfig->spektrum_sat_bind == 0 || rxConfig->spektrum_sat_bind > 10)
+        return;
+
+    gpio.speed = Speed_2MHz;
+    gpio.pin = spekBindPin;
+    gpio.mode = Mode_Out_OD;
+    gpioInit(spekBindPort, &gpio);
+    // RX line, set high
+    digitalHi(spekBindPort, spekBindPin);
+    // Bind window is around 20-140ms after powerup
+    delay(60);
+
+    for (i = 0; i < rxConfig->spektrum_sat_bind; i++) {
+        // RX line, drive low for 120us
+        digitalLo(spekBindPort, spekBindPin);
+        delayMicroseconds(120);
+        // RX line, drive high for 120us
+        digitalHi(spekBindPort, spekBindPin);
+        delayMicroseconds(120);
+    }
+
+#ifndef HARDWARE_BIND_PLUG
+    // If we came here as a result of hard  reset (power up, with mcfg.spektrum_sat_bind set), then reset it back to zero and write config
+    // Don't reset if hardware bind plug is present
+    if (rccReadBkpDr() != BKP_SOFTRESET) {
+    	rxConfig->spektrum_sat_bind = 0;
+        writeEEPROM(1, true);
+    }
+#endif
+
+}