Line 16... |
Line 16... |
16 |
#define SPI_MODE_0 (SPI_L_TO_H | SPI_XMIT_L_TO_H) |
16 |
#define SPI_MODE_0 (SPI_L_TO_H | SPI_XMIT_L_TO_H) |
17 |
#define SPI_MODE_1 (SPI_L_TO_H) |
17 |
#define SPI_MODE_1 (SPI_L_TO_H) |
18 |
#define SPI_MODE_2 (SPI_H_TO_L) |
18 |
#define SPI_MODE_2 (SPI_H_TO_L) |
19 |
#define SPI_MODE_3 (SPI_H_TO_L | SPI_XMIT_L_TO_H) |
19 |
#define SPI_MODE_3 (SPI_H_TO_L | SPI_XMIT_L_TO_H) |
20 |
|
20 |
|
21 |
float a0; |
21 |
float a0; // correctiaon coefficients |
22 |
float b1; |
22 |
float b1; |
23 |
float b2; |
23 |
float b2; |
24 |
float c12; |
24 |
float c12; |
25 |
|
25 |
|
26 |
|
26 |
|
Line 36... |
Line 36... |
36 |
spi_write(0x88); // get MSB for a0 |
36 |
spi_write(0x88); // get MSB for a0 |
37 |
a0_MSB = spi_read(0x00); |
37 |
a0_MSB = spi_read(0x00); |
38 |
spi_write(0x8A); // get LSB for a0 |
38 |
spi_write(0x8A); // get LSB for a0 |
39 |
a0_LSB = spi_read(0x00); |
39 |
a0_LSB = spi_read(0x00); |
40 |
|
40 |
|
41 |
spi_write(0x8C); // get MSB for a0 |
41 |
spi_write(0x8C); // get MSB for b1 |
42 |
b1_MSB = spi_read(0x00); |
42 |
b1_MSB = spi_read(0x00); |
43 |
spi_write(0x8E); // get LSB for a0 |
43 |
spi_write(0x8E); // get LSB for b1 |
44 |
b1_LSB = spi_read(0x00); |
44 |
b1_LSB = spi_read(0x00); |
45 |
|
45 |
|
46 |
spi_write(0x90); // get MSB for a0 |
46 |
spi_write(0x90); // get MSB for b2 |
47 |
b2_MSB = spi_read(0x00); |
47 |
b2_MSB = spi_read(0x00); |
48 |
spi_write(0x92); // get LSB for a0 |
48 |
spi_write(0x92); // get LSB for b2 |
49 |
b2_LSB = spi_read(0x00); |
49 |
b2_LSB = spi_read(0x00); |
50 |
|
50 |
|
51 |
spi_write(0x94); // get MSB for a0 |
51 |
spi_write(0x94); // get MSB for c12 |
52 |
c12_MSB = spi_read(0x00); |
52 |
c12_MSB = spi_read(0x00); |
53 |
spi_write(0x96); // get LSB for a0 |
53 |
spi_write(0x96); // get LSB for c12 |
54 |
c12_LSB = spi_read(0x00); |
54 |
c12_LSB = spi_read(0x00); |
55 |
|
55 |
|
56 |
spi_read(0x00); |
56 |
spi_read(0x00); |
57 |
output_high(CSN_SPI); |
57 |
output_high(CSN_SPI); |
- |
|
58 |
|
- |
|
59 |
// translate to floating point number |
58 |
|
60 |
|
59 |
a0 = ((unsigned int16) a0_MSB << 5) + (a0_LSB >> 3) + (a0_LSB & 0x07)/8.0; |
61 |
a0 = ((unsigned int16) a0_MSB << 5) + (a0_LSB >> 3) + (a0_LSB & 0x07)/8.0; |
60 |
b1 = ((((b1_MSB & 0x1F) * 0x100) + b1_LSB) / 8192.0) - 3; |
62 |
b1 = ((((b1_MSB & 0x1F) * 0x100) + b1_LSB) / 8192.0) - 3; |
61 |
b2 = ((((unsigned int16) (b2_MSB - 0x80) << 8) + b2_LSB)/ 16384.0) - 2; |
63 |
b2 = ((((unsigned int16) (b2_MSB - 0x80) << 8) + b2_LSB)/ 16384.0) - 2; |
62 |
c12 =(((c12_MSB * 0x100) + c12_LSB)/16777216.0); |
64 |
c12 =(((c12_MSB * 0x100) + c12_LSB)/16777216.0); |
63 |
|
- |
|
64 |
printf("%4.3f %1.5f %1.5f %1.9f \r\n", a0, b1, b2, c12); |
- |
|
65 |
|
- |
|
66 |
} |
65 |
} |
67 |
|
66 |
|
68 |
float MPL_get_pressure() |
67 |
float MPL_get_pressure() |
69 |
{ |
68 |
{ |
70 |
unsigned int8 LSB_data, MSB_data; |
69 |
unsigned int8 LSB_data, MSB_data; |
Line 94... |
Line 93... |
94 |
LSB_data = spi_read(0x00); |
93 |
LSB_data = spi_read(0x00); |
95 |
spi_read(0x00); |
94 |
spi_read(0x00); |
96 |
output_high(CSN_SPI); |
95 |
output_high(CSN_SPI); |
97 |
|
96 |
|
98 |
ADC_temperature = (((unsigned int16) MSB_data << 8) + LSB_data ) >> 6; // conversion of 8bit registers to 16bit variable |
97 |
ADC_temperature = (((unsigned int16) MSB_data << 8) + LSB_data ) >> 6; // conversion of 8bit registers to 16bit variable |
99 |
|
- |
|
100 |
printf("%lu %lu \r\n", ADC_pressure, ADC_temperature); |
- |
|
101 |
|
98 |
|
102 |
Pcomp = (a0 + (b1 + c12 * ADC_temperature) * ADC_pressure + b2 * ADC_temperature ); |
99 |
Pcomp = (a0 + (b1 + c12 * ADC_temperature) * ADC_pressure + b2 * ADC_temperature ); // compute relative compensated pressure |
- |
|
100 |
|
- |
|
101 |
return (Pcomp * ((115.0 - 50.0)/1023.0) + 50.0); // return absolute pressure |
- |
|
102 |
} |
- |
|
103 |
|
- |
|
104 |
float MPL_get_temperature() |
- |
|
105 |
{ |
- |
|
106 |
unsigned int8 LSB_data, MSB_data; |
- |
|
107 |
unsigned int16 ADC_temperature; |
- |
|
108 |
|
- |
|
109 |
output_low(CSN_SPI); //Start temperature and pressure conversion |
- |
|
110 |
spi_write(0x22); |
- |
|
111 |
spi_write(0x00); |
- |
|
112 |
output_high(CSN_SPI); |
103 |
|
113 |
|
- |
|
114 |
delay_ms(10); |
- |
|
115 |
|
- |
|
116 |
output_low(CSN_SPI); |
- |
|
117 |
spi_write(0x84); |
104 |
printf("%f \r\n", Pcomp); |
118 |
MSB_data = spi_read(0x00); |
- |
|
119 |
spi_write(0x86); // get LSB for Temperature |
- |
|
120 |
LSB_data = spi_read(0x00); |
- |
|
121 |
spi_read(0x00); |
- |
|
122 |
output_high(CSN_SPI); |
105 |
|
123 |
|
- |
|
124 |
ADC_temperature = (((unsigned int16) MSB_data << 8) + LSB_data ) >> 6; // conversion of 8bit registers to 16bit variable |
- |
|
125 |
|
106 |
return (Pcomp * ((115.0 - 50.0)/1023.0) + 50.0); |
126 |
return ( ((float) ADC_temperature - 498.0)/-5.35) + 25.0; // return temperature in deg C |
107 |
} |
127 |
} |
108 |
|
128 |
|
109 |
void main() |
129 |
void main() |
110 |
{ |
130 |
{ |
111 |
printf("Start \r\n"); |
131 |
printf("Start \r\n"); |
112 |
setup_spi(SPI_MASTER | SPI_MODE_0 | SPI_CLK_DIV_64); |
132 |
setup_spi(SPI_MASTER | SPI_MODE_0 | SPI_CLK_DIV_64); |
113 |
output_high(CSN_SPI); |
133 |
output_high(CSN_SPI); |
114 |
delay_ms(100); |
134 |
delay_ms(100); |
115 |
|
135 |
|
116 |
MPL_init(); |
136 |
MPL_init(); // get correction coeffivcients from the sensor |
117 |
|
137 |
|
118 |
while(true) |
138 |
while(true) |
119 |
{ |
139 |
{ |
120 |
// MPL_init(); |
- |
|
121 |
printf("%f \r\n", MPL_get_pressure()); |
140 |
printf("%f %f \r\n", MPL_get_pressure(), MPL_get_temperature()); |
122 |
// printf("%ld %ld %ld %ld \r\n",a0, b1, b2, c12); |
- |
|
123 |
//MPL_get_pressure(); |
- |
|
124 |
|
- |
|
125 |
delay_ms(500); |
141 |
delay_ms(500); |
126 |
} |
142 |
} |
127 |
} |
143 |
} |