diff --git a/Multiprotocol/Symax_nrf24l01.ino b/Multiprotocol/Symax_nrf24l01.ino
index 3506140..60ea9e9 100644
--- a/Multiprotocol/Symax_nrf24l01.ino
+++ b/Multiprotocol/Symax_nrf24l01.ino
@@ -30,6 +30,7 @@
#define SYMAX_FLAG_VIDEO 0x02
#define SYMAX_FLAG_PICTURE 0x04
#define SYMAX_FLAG_HEADLESS 0x08
+#define SYMAX_XTRM_RATES 0x10
#define SYMAX_PAYLOADSIZE 10 // receive data pipes set to this size, but unused
#define SYMAX_MAX_PACKET_LENGTH 16 // X11,X12,X5C-1 10-byte, X5C 16-byte
@@ -58,6 +59,7 @@ static void __attribute__((unused)) SYMAX_read_controls()
{
// Protocol is registered AETRF, that is
// Aileron is channel 1, Elevator - 2, Throttle - 3, Rudder - 4, Flip control - 5
+ // Extended (trim-added) Rates - 6, Photo - 7, Video - 8, Headless - 9
aileron = convert_channel_s8b(AILERON);
elevator = convert_channel_s8b(ELEVATOR);
throttle = convert_channel_8b(THROTTLE);
@@ -67,6 +69,9 @@ static void __attribute__((unused)) SYMAX_read_controls()
// Channel 5
if (Servo_AUX1)
flags = SYMAX_FLAG_FLIP;
+ // Channel 6
+ if (Servo_AUX2)
+ flags |= SYMAX_XTRM_RATES;
// Channel 7
if (Servo_AUX3)
flags |= SYMAX_FLAG_PICTURE;
@@ -76,6 +81,7 @@ static void __attribute__((unused)) SYMAX_read_controls()
// Channel 9
if (Servo_AUX5)
flags |= SYMAX_FLAG_HEADLESS;
+ flags &= ~SYMAX_XTRM_RATES; // Extended rates & headless incompatible
}
#define X5C_CHAN2TRIM(X) ((((X) & 0x80 ? 0xff - (X) : 0x80 + (X)) >> 2) + 0x20)
@@ -98,9 +104,15 @@ static void __attribute__((unused)) SYMAX_build_packet_x5c(uint8_t bind)
packet[1] = rudder;
packet[2] = elevator ^ 0x80; // reversed from default
packet[3] = aileron;
- packet[4] = X5C_CHAN2TRIM(rudder ^ 0x80);// drive trims for extra control range
- packet[5] = X5C_CHAN2TRIM(elevator);
- packet[6] = X5C_CHAN2TRIM(aileron ^ 0x80);
+ if (flags & SYMAX_XTRM_RATES) { // drive trims for extra control range
+ packet[4] = X5C_CHAN2TRIM(rudder ^ 0x80);
+ packet[5] = X5C_CHAN2TRIM(elevator);
+ packet[6] = X5C_CHAN2TRIM(aileron ^ 0x80);
+ } else {
+ packet[4] = 0x00;
+ packet[5] = 0x00;
+ packet[6] = 0x00;
+ }
packet[7] = 0xae;
packet[8] = 0xa9;
packet[9] = 0x00;
@@ -138,9 +150,14 @@ static void __attribute__((unused)) SYMAX_build_packet(uint8_t bind)
packet[2] = rudder;
packet[3] = aileron;
packet[4] = (flags & SYMAX_FLAG_VIDEO ? 0x80 : 0x00) | (flags & SYMAX_FLAG_PICTURE ? 0x40 : 0x00);
- packet[5] = (elevator >> 2) | 0xc0; //always high rates (bit 7 is rate control)
- packet[6] = (rudder >> 2) | (flags & SYMAX_FLAG_FLIP ? 0x40 : 0x00);
- packet[7] = (aileron >> 2) | (flags & SYMAX_FLAG_HEADLESS ? 0x80 : 0x00);
+ packet[5] = 0xc0; //always high rates (bit 7 is rate control)
+ packet[6] = flags & SYMAX_FLAG_FLIP ? 0x40 : 0x00;
+ packet[7] = flags & SYMAX_FLAG_HEADLESS ? 0x80 : 0x00;
+ if (flags & SYMAX_XTRM_RATES) { // use trims to extend controls
+ packet[5] |= elevator >> 2;
+ packet[6] |= rudder >> 2;
+ packet[7] |= aileron >> 2;
+ }
packet[8] = 0x00;
}
packet[9] = SYMAX_checksum(packet);
diff --git a/docs/Models.md b/docs/Models.md
index a9d8293..0aaa547 100644
--- a/docs/Models.md
+++ b/docs/Models.md
@@ -7,9 +7,9 @@ The Deviation project (on which this project was based) have a useful list of mo
## Channel Map
-CH1|CH2|CH3|CH4|CH5|CH6|CH7|CH8
----|---|---|---|---|---|---|---
-A|E|T|R|FLIP|RATES|PICTURE|VIDEO
+CH1|CH2|CH3|CH4|CH5|CH6|CH7|CH8|CH9
+---|---|---|---|---|---|---|---|---
+A|E|T|R|FLIP|RATES|PICTURE|VIDEO|HEADLESS
## Binding
There are no special binding instructions. The model powers up in Autobind mode and expects the bind sequence from the transmitter within the first 4-5 seconds.
@@ -45,6 +45,25 @@ One of the most annoying functions on the Syma X5C is that the motors stop when
1. When you want to fly in "idle-up" mode flick the switch and your stabilization will always be active.
1. Remeber to switch off idle-up as soon as the quad lands (or crashes - to avoid damage to the motors)
+### Additional notes on rates:
+
+The SymaX driver can add full trim to the control output. Doing so enables
+dramatic rates, steep angles, and high speeds. If CH6 is low, the usual Syma
+full rates will be in effect. If CH6 is high, the SymaX extreme trim rates will be
+in effect. Be cautious when first trying out the extreme rates.
+
+The extreme rates do not work with with headless mode because in this
+mode the trim and the primary control directions may not be aligned - the
+primary control directions will be based on the headless mode, but the trims
+remain based upon the quadcopter's heading. So extreme rates are disabled
+when headless mode is selected.
+
+Be aware that the use of extreme rates and the resulting steep angles will
+disorient the gyro responsible for maintaining headless mode, and that the
+direction the quadcopter thinks you selected for headless mode may not be
+correct after especially wild flights.
+
+
# Inductrix (Horizon Hobby)
