Mirror
/
ardupilot
mirror of https://github.com/ArduPilot/ardupilot
5
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

AP_Baro: read 4 pressure values for every temperature value on BMP085

This commit is contained in:
Andrew Tridgell 2013-01-09 23:44:26 +11:00
parent 269804e866
commit 8cb0ed364a
2 changed files with 29 additions and 24 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

37
libraries/AP_Baro/AP_Baro_BMP085.cpp
View File

@ -30,7 +30,6 @@
* Command_ReadPress(): Send commando to read Pressure * Command_ReadPress(): Send commando to read Pressure
* ReadTemp() : Read temp register * ReadTemp() : Read temp register
* ReadPress() : Read press register * ReadPress() : Read press register
* Calculate() : Calculate Temperature and Pressure in real units
* *
* *
*/ */
@ -76,17 +75,17 @@ bool AP_Baro_BMP085::init()
return false; return false;
} }
ac1 = ((int)buff[0] << 8) | buff[1]; ac1 = ((int16_t)buff[0] << 8) | buff[1];
ac2 = ((int)buff[2] << 8) | buff[3]; ac2 = ((int16_t)buff[2] << 8) | buff[3];
ac3 = ((int)buff[4] << 8) | buff[5]; ac3 = ((int16_t)buff[4] << 8) | buff[5];
ac4 = ((int)buff[6] << 8) | buff[7]; ac4 = ((int16_t)buff[6] << 8) | buff[7];
ac5 = ((int)buff[8] << 8) | buff[9]; ac5 = ((int16_t)buff[8] << 8) | buff[9];
ac6 = ((int)buff[10] << 8) | buff[11]; ac6 = ((int16_t)buff[10] << 8) | buff[11];
b1 = ((int)buff[12] << 8) | buff[13]; b1 = ((int16_t)buff[12] << 8) | buff[13];
b2 = ((int)buff[14] << 8) | buff[15]; b2 = ((int16_t)buff[14] << 8) | buff[15];
mb = ((int)buff[16] << 8) | buff[17]; mb = ((int16_t)buff[16] << 8) | buff[17];
mc = ((int)buff[18] << 8) | buff[19]; mc = ((int16_t)buff[18] << 8) | buff[19];
md = ((int)buff[20] << 8) | buff[21]; md = ((int16_t)buff[20] << 8) | buff[21];
//Send a command to read Temp //Send a command to read Temp
Command_ReadTemp(); Command_ReadTemp();
@ -109,20 +108,24 @@ void AP_Baro_BMP085::accumulate(void)
} }
if (BMP085_State == 0) { if (BMP085_State == 0) {
ReadTemp(); ReadTemp();
Command_ReadPress();
} else { } else {
ReadPress(); ReadPress();
Calculate(); Calculate();
Command_ReadTemp();
} }
BMP085_State ^= 1; BMP085_State++;
if (BMP085_State == 5) {
BMP085_State = 0;
Command_ReadTemp();
} else {
Command_ReadPress();
}
} }
// Read the sensor using accumulated data // Read the sensor using accumulated data
uint8_t AP_Baro_BMP085::read() uint8_t AP_Baro_BMP085::read()
{ {
if (BMP_DATA_READY()) { if (_count == 0 && BMP_DATA_READY()) {
accumulate(); accumulate();
} }
if (_count == 0) { if (_count == 0) {
@ -133,6 +136,7 @@ uint8_t AP_Baro_BMP085::read()
Temp = _temp_sum / _count; Temp = _temp_sum / _count;
Press = _press_sum / _count; Press = _press_sum / _count;
_pressure_samples = _count;
_count = 0; _count = 0;
_temp_sum = 0; _temp_sum = 0;
_press_sum = 0; _press_sum = 0;
@ -219,6 +223,7 @@ void AP_Baro_BMP085::ReadTemp()
RawTemp = _temp_filter.apply(_temp_sensor); RawTemp = _temp_filter.apply(_temp_sensor);
} }
// Calculate Temperature and Pressure in real units. // Calculate Temperature and Pressure in real units.
void AP_Baro_BMP085::Calculate() void AP_Baro_BMP085::Calculate()
{ {

14
libraries/AP_Baro/examples/AP_Baro_BMP085_test/AP_Baro_BMP085_test.pde
View File

@ -46,16 +46,14 @@ void loop()
float tmp_float; float tmp_float;
static uint32_t last_print; static uint32_t last_print;
bmp085.accumulate(); // accumulate values at 100Hz
// accumulate values at 50Hz
if ((hal.scheduler->micros()- timer) > 20000L) { if ((hal.scheduler->micros()- timer) > 20000L) {
bmp085.read(); bmp085.accumulate();
timer = hal.scheduler->micros(); timer = hal.scheduler->micros();
} }
// print at 2Hz // print at 10Hz
if ((hal.scheduler->millis()- last_print) >= 500) { if ((hal.scheduler->millis()- last_print) >= 100) {
uint32_t start = hal.scheduler->micros(); uint32_t start = hal.scheduler->micros();
last_print = hal.scheduler->millis(); last_print = hal.scheduler->millis();
bmp085.read(); bmp085.read();
@ -73,7 +71,9 @@ void loop()
tmp_float = pow(tmp_float, 0.190295); tmp_float = pow(tmp_float, 0.190295);
float alt = 44330.0 * (1.0 - tmp_float); float alt = 44330.0 * (1.0 - tmp_float);
hal.console->print(alt); hal.console->print(alt);
hal.console->printf(" t=%lu", read_time); hal.console->printf(" t=%lu samples=%u",
read_time,
(unsigned)bmp085.get_pressure_samples());
hal.console->println(); hal.console->println();
} }
} }