Mirror/ardupilot
5
0
Fork 0
mirror of https://github.com/ArduPilot/ardupilot synced 2025-03-05 21:23:58 -04:00
Code Issues Packages Projects Releases Wiki Activity

HAL_Linux: Optimize bandwidth for RCOutput_Navio

Browse Source 
40% less bytes in I2C transactions for PCA9685.
This commit is contained in:
Mikhail Avkhimenia 2014-11-17 13:14:51 +03:00 committed by Andrew Tridgell
parent 50459bdca0
commit 955753f3f0
1 changed files with 7 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
libraries/AP_HAL_Linux/RCOutput_Navio.cpp
View File

@ -46,6 +46,10 @@ void LinuxRCOutput_Navio::set_freq(uint32_t chmask, uint16_t freq_hz)
uint8_t prescale = round(24576000.f / 4096.f / freq_hz) - 1;
hal.i2c->writeRegister(PCA9685_ADDRESS, PCA9685_RA_PRE_SCALE, prescale);
// Reset all channels
uint8_t data[4] = {0x00, 0x00, 0x00, 0x00};
hal.i2c->writeRegisters(PCA9685_ADDRESS, PCA9685_RA_ALL_LED_ON_L, 4, data);
// Enable external clocking
hal.i2c->writeRegister(PCA9685_ADDRESS, PCA9685_RA_MODE1,
PCA9685_MODE1_SLEEP_BIT | PCA9685_MODE1_EXTCLK_BIT);
@ -90,10 +94,10 @@ void LinuxRCOutput_Navio::write(uint8_t ch, uint16_t period_us)
else
length = round((period_us * 4096) / (1000000.f / _frequency)) - 1;
uint8_t data[4] = {0x00, 0x00, length & 0xFF, length >> 8};
uint8_t data[2] = {length & 0xFF, length >> 8};
uint8_t status = hal.i2c->writeRegisters(PCA9685_ADDRESS,
PCA9685_RA_LED0_ON_L + 4 * (ch + 3),
4,
PCA9685_RA_LED0_OFF_L + 4 * (ch + 3),
2,
data);
_i2c_sem->give();