Rev Author Line No. Line
2767 kaklik 1 #include <main.h>
2  
3 /*
4 MPL115A1 SDN - +3.3V (always power on)
5 MPL115A1 #CS - PIN_C2
2769 kaklik 6 MPL115A1 DOUT - PIN_C4
7 MPL115A1 DIN - PIN_C5
2767 kaklik 8 MPL115A1 SCLK - PIN_C3
9 MPL115A1 GND - GND
10 MPL115A1 VDD - +3.3V
11 */
12  
13 #define CSN_SPI PIN_C2
14  
15 // SPI mode definitions.
16 #define SPI_MODE_0 (SPI_L_TO_H | SPI_XMIT_L_TO_H)
17 #define SPI_MODE_1 (SPI_L_TO_H)
18 #define SPI_MODE_2 (SPI_H_TO_L)
19 #define SPI_MODE_3 (SPI_H_TO_L | SPI_XMIT_L_TO_H)
20  
2775 kaklik 21 float a0;
22 float b1;
23 float b2;
24 float c12;
2767 kaklik 25  
26  
2775 kaklik 27 void MPL_init()
2772 kaklik 28 {
29 unsigned int8 a0_MSB, a0_LSB;
30 unsigned int8 b1_MSB, b1_LSB;
31 unsigned int8 b2_MSB, b2_LSB;
32 unsigned int8 c12_MSB, c12_LSB;
2767 kaklik 33  
2772 kaklik 34 output_low(CSN_SPI);
2767 kaklik 35  
2772 kaklik 36 spi_write(0x88); // get MSB for a0
37 a0_MSB = spi_read(0x00);
38 spi_write(0x8A); // get LSB for a0
39 a0_LSB = spi_read(0x00);
2767 kaklik 40  
2772 kaklik 41 spi_write(0x8C); // get MSB for a0
42 b1_MSB = spi_read(0x00);
43 spi_write(0x8E); // get LSB for a0
44 b1_LSB = spi_read(0x00);
2767 kaklik 45  
2772 kaklik 46 spi_write(0x90); // get MSB for a0
47 b2_MSB = spi_read(0x00);
48 spi_write(0x92); // get LSB for a0
49 b2_LSB = spi_read(0x00);
50  
51 spi_write(0x94); // get MSB for a0
52 c12_MSB = spi_read(0x00);
53 spi_write(0x96); // get LSB for a0
54 c12_LSB = spi_read(0x00);
55  
56 spi_read(0x00);
57 output_high(CSN_SPI);
2767 kaklik 58  
2775 kaklik 59 a0 = (a0_MSB << 5) + (a0_LSB >> 3) + (a0_LSB & 0x07)/8.0;
60 b1 = ((((b1_MSB & 0x1F) * 0x100) + b1_LSB) / 8192.0) - 3;
61 b2 = ((((b2_MSB - 0x80) << 8) + b2_LSB)/ 16384.0) - 2;
62 c12 =(((c12_MSB * 0x100) + c12_LSB)/16777216.0);
2772 kaklik 63 }
64  
65 float MPL_get_pressure()
66 {
2774 kaklik 67 unsigned int8 LSB_data, MSB_data;
68 unsigned int16 ADC_pressure, ADC_temperature;
2775 kaklik 69 float Pcomp;
2772 kaklik 70  
71 output_low(CSN_SPI); //Start temperature and pressure conversion
72 spi_write(0x24);
73 spi_write(0x00);
2767 kaklik 74 output_high(CSN_SPI);
75  
2774 kaklik 76 delay_ms(10);
2772 kaklik 77  
78 output_low(CSN_SPI); // get MSB for Pressure
79 spi_write(0x80);
2775 kaklik 80 MSB_data = spi_read(0x00);
81 spi_write(0x82); // get LSB for Pressure
2772 kaklik 82 LSB_data = spi_read(0x00);
2774 kaklik 83 output_high(CSN_SPI);
2767 kaklik 84  
2774 kaklik 85 printf("%lX %lX\r\n", MSB_data, LSB_data);
2775 kaklik 86 ADC_pressure = (((unsigned int16) MSB_data << 8) + LSB_data ) >> 6; // conversion of 8bit registers to 16bit variable
2767 kaklik 87  
2774 kaklik 88 output_low(CSN_SPI);
2772 kaklik 89 spi_write(0x84);
2775 kaklik 90 MSB_data = spi_read(0x00);
91 spi_write(0x86); // get LSB for Temperature
2772 kaklik 92 LSB_data = spi_read(0x00);
93 spi_read(0x00);
94 output_high(CSN_SPI);
95  
2774 kaklik 96 printf("%lX %lX\r\n", MSB_data, LSB_data);
2775 kaklik 97 ADC_temperature = (((unsigned int16) MSB_data << 8) + LSB_data ) >> 6; // conversion of 8bit registers to 16bit variable
2772 kaklik 98  
2775 kaklik 99 printf("%lu %lu \r\n", ADC_pressure, ADC_temperature);
100  
101 Pcomp = (a0 + (b1 + c12 * ADC_temperature) * ADC_pressure + b2 * ADC_temperature );
2772 kaklik 102  
2775 kaklik 103 return (Pcomp * ((115.0 - 50.0)/1023.0) + 50.0);
2767 kaklik 104 }
2772 kaklik 105  
106 void main()
107 {
108 printf("Start \r\n");
109 setup_spi(SPI_MASTER | SPI_MODE_0 | SPI_CLK_DIV_64);
110 output_high(CSN_SPI);
111 delay_ms(100);
112  
113 MPL_init();
114  
115 while(true)
116 {
2774 kaklik 117 // MPL_init();
2775 kaklik 118 printf("%f \r\n", MPL_get_pressure());
2774 kaklik 119 // printf("%ld %ld %ld %ld \r\n",a0, b1, b2, c12);
2775 kaklik 120 //MPL_get_pressure();
2774 kaklik 121  
122 delay_ms(500);
2772 kaklik 123 }
124 }