From d96ba9fa463a5bc7bf0259cc909adb98c3e3feec Mon Sep 17 00:00:00 2001
From: pascallanger <planger@mathworks.com>
Date: Sun, 4 Sep 2016 16:48:52 +0200
Subject: [PATCH] Flysky Flash space optimization

---
 Multiprotocol/FlySky_a7105.ino | 65 ++++++++++++++++++----------------
 1 file changed, 35 insertions(+), 30 deletions(-)

diff --git a/Multiprotocol/FlySky_a7105.ino b/Multiprotocol/FlySky_a7105.ino
index a7f4033..43ccffd 100644
--- a/Multiprotocol/FlySky_a7105.ino
+++ b/Multiprotocol/FlySky_a7105.ino
@@ -50,10 +50,6 @@ enum {
 	FLAG_V912_BTMBTN= 0x80,
 };
 
-uint8_t chanrow;
-uint8_t chancol;
-uint8_t chanoffset;
-
 const uint8_t PROGMEM V912_X17_SEQ[10] =  { 0x14, 0x31, 0x40, 0x49, 0x49,    // sometime first byte is 0x15 ?
 										0x49, 0x49, 0x49, 0x49, 0x49, }; 
 
@@ -151,25 +147,6 @@ static void __attribute__((unused)) flysky_build_packet(uint8_t init)
     flysky_apply_extension_flags();
 }
 
-const uint8_t PROGMEM tx_channels[16][16] = {
-  {0x0a, 0x5a, 0x14, 0x64, 0x1e, 0x6e, 0x28, 0x78, 0x32, 0x82, 0x3c, 0x8c, 0x46, 0x96, 0x50, 0xa0},
-  {0xa0, 0x50, 0x96, 0x46, 0x8c, 0x3c, 0x82, 0x32, 0x78, 0x28, 0x6e, 0x1e, 0x64, 0x14, 0x5a, 0x0a},
-  {0x0a, 0x5a, 0x50, 0xa0, 0x14, 0x64, 0x46, 0x96, 0x1e, 0x6e, 0x3c, 0x8c, 0x28, 0x78, 0x32, 0x82},
-  {0x82, 0x32, 0x78, 0x28, 0x8c, 0x3c, 0x6e, 0x1e, 0x96, 0x46, 0x64, 0x14, 0xa0, 0x50, 0x5a, 0x0a},
-  {0x28, 0x78, 0x0a, 0x5a, 0x50, 0xa0, 0x14, 0x64, 0x1e, 0x6e, 0x3c, 0x8c, 0x32, 0x82, 0x46, 0x96},
-  {0x96, 0x46, 0x82, 0x32, 0x8c, 0x3c, 0x6e, 0x1e, 0x64, 0x14, 0xa0, 0x50, 0x5a, 0x0a, 0x78, 0x28},
-  {0x50, 0xa0, 0x28, 0x78, 0x0a, 0x5a, 0x1e, 0x6e, 0x3c, 0x8c, 0x32, 0x82, 0x46, 0x96, 0x14, 0x64},
-  {0x64, 0x14, 0x96, 0x46, 0x82, 0x32, 0x8c, 0x3c, 0x6e, 0x1e, 0x5a, 0x0a, 0x78, 0x28, 0xa0, 0x50},
-  {0x50, 0xa0, 0x46, 0x96, 0x3c, 0x8c, 0x28, 0x78, 0x0a, 0x5a, 0x32, 0x82, 0x1e, 0x6e, 0x14, 0x64},
-  {0x64, 0x14, 0x6e, 0x1e, 0x82, 0x32, 0x5a, 0x0a, 0x78, 0x28, 0x8c, 0x3c, 0x96, 0x46, 0xa0, 0x50},
-  {0x46, 0x96, 0x3c, 0x8c, 0x50, 0xa0, 0x28, 0x78, 0x0a, 0x5a, 0x1e, 0x6e, 0x32, 0x82, 0x14, 0x64},
-  {0x64, 0x14, 0x82, 0x32, 0x6e, 0x1e, 0x5a, 0x0a, 0x78, 0x28, 0xa0, 0x50, 0x8c, 0x3c, 0x96, 0x46},
-  {0x46, 0x96, 0x0a, 0x5a, 0x3c, 0x8c, 0x14, 0x64, 0x50, 0xa0, 0x28, 0x78, 0x1e, 0x6e, 0x32, 0x82},
-  {0x82, 0x32, 0x6e, 0x1e, 0x78, 0x28, 0xa0, 0x50, 0x64, 0x14, 0x8c, 0x3c, 0x5a, 0x0a, 0x96, 0x46},
-  {0x46, 0x96, 0x0a, 0x5a, 0x50, 0xa0, 0x3c, 0x8c, 0x28, 0x78, 0x1e, 0x6e, 0x32, 0x82, 0x14, 0x64},
-  {0x64, 0x14, 0x82, 0x32, 0x6e, 0x1e, 0x78, 0x28, 0x8c, 0x3c, 0xa0, 0x50, 0x5a, 0x0a, 0x96, 0x46},
-};
-
 uint16_t ReadFlySky()
 {
     if (bind_counter)
@@ -183,28 +160,56 @@ uint16_t ReadFlySky()
 	else
 	{
 		flysky_build_packet(0);
-        A7105_WriteData(21, pgm_read_byte_near(&tx_channels[chanrow][chancol])-chanoffset);
-        chancol = (chancol + 1) % 16;
-        if (! chancol) //Keep transmit power updated
-			A7105_SetPower();
+        A7105_WriteData(21, hopping_frequency[hopping_frequency_no]);
+        hopping_frequency_no = (hopping_frequency_no + 1) & 0x0F;
+		A7105_SetPower();
     }
 	return 1510;	//1460 on deviation but not working with the latest V911 bricks... Turnigy 9X v2 is 1533, Flysky TX for 9XR/9XR Pro is 1510, V911 TX is 1490.
 }
 
-uint16_t initFlySky() {
+const uint8_t PROGMEM tx_channels[8][4] = {
+	{ 0x12, 0x34, 0x56, 0x78},
+	{ 0x18, 0x27, 0x36, 0x45},
+	{ 0x41, 0x82, 0x36, 0x57},
+	{ 0x84, 0x13, 0x65, 0x72},
+	{ 0x87, 0x64, 0x15, 0x32},
+	{ 0x76, 0x84, 0x13, 0x52},
+	{ 0x71, 0x62, 0x84, 0x35},
+	{ 0x71, 0x86, 0x43, 0x52}
+};
+
+uint16_t initFlySky()
+{
+	uint8_t chanrow;
+	uint8_t chanoffset;
+	uint8_t temp;
+
 	A7105_Init(INIT_FLYSKY);	//flysky_init();
 	
 	if ((rx_tx_addr[3]&0xF0) > 0x90) // limit offset to 9 as higher values don't work with some RX (ie V912)
 		rx_tx_addr[3]=rx_tx_addr[3]-0x70;
 	chanrow=rx_tx_addr[3] & 0x0F;
-	chancol=0;
 	chanoffset=rx_tx_addr[3]/16;
 	
+	// Build frequency hop table
+	for(uint8_t i=0;i<16;i++)
+	{
+		temp=pgm_read_byte_near(&tx_channels[chanrow>>1][i>>2]);
+		if(i&0x01)
+			temp&=0x0F;
+		else
+			temp>>=4;
+		temp*=0x0A;
+		if(i&0x02)
+			temp+=0x50;
+		hopping_frequency[((chanrow&1)?15-i:i)]=temp-chanoffset;
+	}
+	hopping_frequency_no=0;
+	
 	if(IS_AUTOBIND_FLAG_on)
 		bind_counter = FLYSKY_BIND_COUNT;
 	else
 		bind_counter = 0;
 	return 2400;
 }
-
 #endif