Reduce maximum servos from 10 to 8.

1) the 2 extra servos were not used for anything, yet.
2) the MSP packet to set ALL the servo configurations in one go is
larger than the MSP input buffer size.

Likely the MSP_SET_SERVO_CONF should be updated with command that takes
an index of a servo to configure, as per mode ranges/colors/leds/etc.

Fixes #1002

src/main/config/config.c

@@ -128,7 +128,7 @@ static uint32_t activeFeaturesLatch = 0;
 static uint8_t currentControlRateProfileIndex = 0;
 controlRateConfig_t *currentControlRateProfile;
 
-static const uint8_t EEPROM_CONF_VERSION = 101;
+static const uint8_t EEPROM_CONF_VERSION = 102;
 
 static void resetAccelerometerTrims(flightDynamicsTrims_t *accelerometerTrims)
 {
@@ -348,7 +348,7 @@ static void resetConf(void)
 {
     int i;
 #ifdef USE_SERVOS
-    int8_t servoRates[MAX_SUPPORTED_SERVOS] = { 30, 30, 100, 100, 100, 100, 100, 100, 100, 100 };
+    int8_t servoRates[MAX_SUPPORTED_SERVOS] = { 30, 30, 100, 100, 100, 100, 100, 100 };
     ;
 #endif
 

src/main/drivers/pwm_mapping.h

@@ -18,10 +18,10 @@
 #pragma once
 
 #define MAX_PWM_MOTORS  12
-#define MAX_PWM_SERVOS  10
+#define MAX_PWM_SERVOS  8
 
 #define MAX_MOTORS  12
-#define MAX_SERVOS  10
+#define MAX_SERVOS  8
 #define MAX_PWM_OUTPUT_PORTS MAX_PWM_MOTORS // must be set to the largest of either MAX_MOTORS or MAX_SERVOS
 
 #if MAX_PWM_OUTPUT_PORTS < MAX_MOTORS || MAX_PWM_OUTPUT_PORTS < MAX_SERVOS

src/main/flight/mixer.h

@@ -18,7 +18,7 @@
 #pragma once
 
 #define MAX_SUPPORTED_MOTORS 12
-#define MAX_SUPPORTED_SERVOS 10
+#define MAX_SUPPORTED_SERVOS 8
 #define YAW_JUMP_PREVENTION_LIMIT_LOW 80
 #define YAW_JUMP_PREVENTION_LIMIT_HIGH 500
 

src/main/io/serial_msp.c

@@ -308,6 +308,8 @@ static const char * const boardIdentifier = TARGET_BOARD_IDENTIFIER;
 
 #define INBUF_SIZE 64
 
+#define SERVO_CHUNK_SIZE 7
+
 typedef struct box_e {
     const uint8_t boxId;         // see boxId_e
     const char *boxName;            // GUI-readable box name
@@ -619,6 +621,8 @@ void mspReleasePortIfAllocated(serialPort_t *serialPort)
 
 void mspInit(serialConfig_t *serialConfig)
 {
+    BUILD_BUG_ON((SERVO_CHUNK_SIZE * MAX_SUPPORTED_SERVOS) > INBUF_SIZE);
+
     // calculate used boxes based on features and fill availableBoxes[] array
     memset(activeBoxIds, 0xFF, sizeof(activeBoxIds));
 
@@ -1408,18 +1412,26 @@ static bool processInCommand(void)
         break;
     case MSP_SET_SERVO_CONF:
 #ifdef USE_SERVOS
-        for (i = 0; i < MAX_SUPPORTED_SERVOS; i++) {
-            currentProfile->servoConf[i].min = read16();
-            currentProfile->servoConf[i].max = read16();
-            // provide temporary support for old clients that try and send a channel index instead of a servo middle
-            uint16_t potentialServoMiddleOrChannelToForward = read16();
-            if (potentialServoMiddleOrChannelToForward < MAX_SUPPORTED_SERVOS) {
-                currentProfile->servoConf[i].forwardFromChannel = potentialServoMiddleOrChannelToForward;
-            }
-            if (potentialServoMiddleOrChannelToForward >= PWM_RANGE_MIN && potentialServoMiddleOrChannelToForward <= PWM_RANGE_MAX) {
-                currentProfile->servoConf[i].middle = potentialServoMiddleOrChannelToForward;
+        if (currentPort->dataSize % SERVO_CHUNK_SIZE != 0) {
+            debug[0] = currentPort->dataSize;
+            headSerialError(0);
+        } else {
+            uint8_t servoCount = currentPort->dataSize / SERVO_CHUNK_SIZE;
+
+            for (i = 0; i < MAX_SUPPORTED_SERVOS && i < servoCount; i++) {
+                currentProfile->servoConf[i].min = read16();
+                currentProfile->servoConf[i].max = read16();
+
+                // provide temporary support for old clients that try and send a channel index instead of a servo middle
+                uint16_t potentialServoMiddleOrChannelToForward = read16();
+                if (potentialServoMiddleOrChannelToForward < MAX_SUPPORTED_SERVOS) {
+                    currentProfile->servoConf[i].forwardFromChannel = potentialServoMiddleOrChannelToForward;
+                }
+                if (potentialServoMiddleOrChannelToForward >= PWM_RANGE_MIN && potentialServoMiddleOrChannelToForward <= PWM_RANGE_MAX) {
+                    currentProfile->servoConf[i].middle = potentialServoMiddleOrChannelToForward;
+                }
+                currentProfile->servoConf[i].rate = read8();
             }
-            currentProfile->servoConf[i].rate = read8();
         }
 #endif
         break;