+static uint bmp_read(uint reg, uint bytes)
+{
+ LL_I2C_ClearFlag_STOP(I2C1);
+ LL_I2C_ClearFlag_BERR(I2C1);
+ LL_I2C_HandleTransfer(I2C1, 0xee, LL_I2C_ADDRSLAVE_7BIT, 1, LL_I2C_MODE_SOFTEND, LL_I2C_GENERATE_START_WRITE);
+ while (!LL_I2C_IsActiveFlag_TXE(I2C1))
+ ;
+ LL_I2C_TransmitData8(I2C1, reg);
+ while (!LL_I2C_IsActiveFlag_TC(I2C1))
+ ;
+ LL_I2C_HandleTransfer(I2C1, 0xef, LL_I2C_ADDRSLAVE_7BIT, bytes, LL_I2C_MODE_AUTOEND, LL_I2C_GENERATE_RESTART_7BIT_READ);
+
+ uint d = 0;
+ for (uint i=0; i<bytes; i++)
+ {
+ while (!LL_I2C_IsActiveFlag_RXNE(I2C1))
+ ;
+ d = (d << 8) | LL_I2C_ReceiveData8(I2C1);
+ }
+
+ return d;
+}
+
+static uint bmp_measure(uint type, uint bytes)
+{
+ LL_I2C_HandleTransfer(I2C1, 0xee, LL_I2C_ADDRSLAVE_7BIT, 2, LL_I2C_MODE_AUTOEND, LL_I2C_GENERATE_START_WRITE);
+ while (!LL_I2C_IsActiveFlag_TXE(I2C1))
+ ;
+ LL_I2C_TransmitData8(I2C1, 0xf4);
+ while (!LL_I2C_IsActiveFlag_TXE(I2C1))
+ ;
+ LL_I2C_TransmitData8(I2C1, type);
+ while (!LL_I2C_IsActiveFlag_STOP(I2C1))
+ ;
+
+ while (!LL_GPIO_IsInputPinSet(BMP_DONE_GPIO_Port, BMP_DONE_Pin))
+ ;
+
+ return bmp_read(0xf6, bytes);
+}
+
+// Formulae from BMP085 specs
+void bmp_recalc(uint UT, uint UP, uint oss, u16 cc[11], int *tt, int *pp)
+{
+ s16 AC1 = cc[0];
+ s16 AC2 = cc[1];
+ s16 AC3 = cc[2];
+ u16 AC4 = cc[3];
+ u16 AC5 = cc[4];
+ u16 AC6 = cc[5];
+ s16 B1 = cc[6];
+ s16 B2 = cc[7];
+ s16 MB = cc[8];
+ s16 MC = cc[9];
+ s16 MD = cc[10];
+ UP >>= (8-oss);
+
+ int X1 = (UT-AC6)*AC5 / (1<<15);
+ int X2 = MC*(1<<11) / (X1+MD);
+ int B5 = X1 + X2;
+ int T = (B5+8) / (1<<4);
+ *tt = T;
+
+ int B6 = B5 - 4000;
+ X1 = (B2*(B6*B6/(1<<12))) / (1<<11);
+ X2 = AC2 * B6 / (1<<11);
+ int X3 = X1 + X2;
+ int B3 = (((AC1*4 + X3) << oss) + 2) / 4;
+ X1 = AC3 * B6 / (1<<13);
+ X2 = (B1*(B6*B6/(1<<12))) / (1<<16);
+ X3 = ((X1+X2) + 2) / (1<<2);
+ uint B4 = (uint)(AC4 * (X3 + 32768)) / (1U<<15);
+ uint B7 = (uint)(UP-B3) * (uint)(50000>>oss);
+ int p;
+ if (B7 < 0x80000000)
+ p = (B7*2) / B4;
+ else
+ p = B7 / B4 * 2;
+ X1 = (p/(1<<8)) * (p/(1<<8));
+ X1 = (X1*3038) / (1<<16);
+ X2 = (-7357*p) / (1<<16);
+ p = p + (X1 + X2 + 3791) / (1<<4);
+ *pp = p;
+}
+