AMTS/Mieke/SW/ODD/bma.c
2018-03-18 23:43:59 +01:00

62 lines
2.1 KiB
C

#include "bma.h"
#define BMA_ADDR (uint8_t)0x70 // 0b01110000
// ---- Vendor address part
// --- User address part
// - Keep free for R/W bit (set by I2C_Send7bitAddress())
void bma_init(void)
{
i2c1_init();
}
void bma_get_acc(uint8_t *X, uint8_t *Y, uint8_t *Z)
{
int16_t acc[3];
// Select first register address to read
I2C_GenerateSTART(I2C1, ENABLE);
while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_MODE_SELECT));
I2C_Send7bitAddress(I2C1, BMA_ADDR, I2C_Direction_Transmitter);
while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED));
I2C_SendData(I2C1, 0x02);
while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_TRANSMITTED));
I2C_GenerateSTOP(I2C1, ENABLE);
I2C_GenerateSTART(I2C1, ENABLE);
I2C_AcknowledgeConfig(I2C1, ENABLE);
while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_MODE_SELECT));
I2C_Send7bitAddress(I2C1, BMA_ADDR, I2C_Direction_Receiver);
while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_RECEIVER_MODE_SELECTED));
// X LSB
while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_RECEIVED));
acc[0] = (I2C_ReceiveData(I2C1) & 0xC0) >> 6;
// X MSB
while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_RECEIVED));
acc[0] = (I2C_ReceiveData(I2C1) & 0xFF) << 2 | (acc[0] & 0x0003);
if(acc[0] & 0x0200) acc[0] |= 0xFC00;
// Y LSB
while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_RECEIVED));
acc[1] = (I2C_ReceiveData(I2C1) & 0xC0) >> 6;
// Y MSB
while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_RECEIVED));
acc[1] = (I2C_ReceiveData(I2C1) & 0xFF) << 2 | (acc[1] & 0x0003);
if(acc[1] & 0x0200) acc[1] |= 0xFC00;
// Z LSB
while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_RECEIVED));
acc[2] = (I2C_ReceiveData(I2C1) & 0xC0) >> 6;
// Z MSB
I2C_AcknowledgeConfig(I2C1, DISABLE);
while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_RECEIVED));
acc[2] = (I2C_ReceiveData(I2C1) & 0xFF) << 2 | (acc[2] & 0x0003);
if(acc[2] & 0x0200) acc[2] |= 0xFC00;
I2C_GenerateSTOP(I2C1, ENABLE);
*X = (acc[0]/4) + 128;
*Y = (acc[1]/4) + 128;
*Z = (acc[2]/4) + 128;
}