david.tahir/QuadMeUp_Crossbow
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

Speed optimization for S.Bus encoding

Browse Source
This commit is contained in:
Pawel Spychalski (DzikuVx)
2017-10-28 22:25:38 +02:00
parent 7bb8544880
commit 72cb29eca2
2 changed files with 12 additions and 3 deletions
Download Patch File Download Diff File Expand all files Collapse all files

4
crossbow.ino
View File

@@ -1,5 +1,5 @@
#define DEVICE_MODE_TX // #define DEVICE_MODE_TX
// #define DEVICE_MODE_RX #define DEVICE_MODE_RX
#define FEATURE_TX_OLED #define FEATURE_TX_OLED

11
sbus.cpp
View File

@@ -12,6 +12,15 @@
#define SBUS_STATE_FAILSAFE 0x08 #define SBUS_STATE_FAILSAFE 0x08
#define SBUS_STATE_SIGNALLOSS 0x04 #define SBUS_STATE_SIGNALLOSS 0x04
/*
Precomputed mapping from 990-2010 to 173:1811
equivalent to
map(channels[i], RC_CHANNEL_MIN, RC_CHANNEL_MAX, SBUS_MIN_OFFSET, SBUS_MAX_OFFSET);
*/
int mapChannelToSbus(int in) {
return (((long) in * 1605l) / 1000l) - 1417;
}
void sbusPreparePacket(uint8_t packet[], int channels[], bool isSignalLoss, bool isFailsafe){ void sbusPreparePacket(uint8_t packet[], int channels[], bool isSignalLoss, bool isFailsafe){
static int output[SBUS_CHANNEL_NUMBER] = {0}; static int output[SBUS_CHANNEL_NUMBER] = {0};
@@ -21,7 +30,7 @@ void sbusPreparePacket(uint8_t packet[], int channels[], bool isSignalLoss, bool
* 173-1811 with middle at 992 S.BUS protocol requires * 173-1811 with middle at 992 S.BUS protocol requires
*/ */
for (uint8_t i = 0; i < SBUS_CHANNEL_NUMBER; i++) { for (uint8_t i = 0; i < SBUS_CHANNEL_NUMBER; i++) {
output[i] = map(channels[i], RC_CHANNEL_MIN, RC_CHANNEL_MAX, SBUS_MIN_OFFSET, SBUS_MAX_OFFSET); output[i] = mapsChannelToSbus(channels[i]);
} }
uint8_t stateByte = 0x00; uint8_t stateByte = 0x00;