sato takumi / Mbed 2 deprecated Prelude_EPS_temp

a

Dependencies:   mbed mcp3208 HeptaTemp

main.cpp@0:709d290281a1, 2022-06-14 (annotated)

Committer:
goro56
Date:
Tue Jun 14 09:22:13 2022 +0000
Revision:
0:709d290281a1
a

Who changed what in which revision?

UserRevisionLine numberNew contents of line
goro56 0:709d290281a1 1 #include "mbed.h"
goro56 0:709d290281a1 2 SPI spi(p11,p12,p13);
goro56 0:709d290281a1 3 DigitalOut cs(p14);
goro56 0:709d290281a1 4 Serial pc(USBTX, USBRX);
goro56 0:709d290281a1 5 int main(void)
goro56 0:709d290281a1 6 {
goro56 0:709d290281a1 7 int bit = 8;
goro56 0:709d290281a1 8 spi.format(bit,0);
goro56 0:709d290281a1 9 spi.frequency(2000000); //VDD=5Vの場合は2MHz．
goro56 0:709d290281a1 10 printf("\r\n");
goro56 0:709d290281a1 11 printf("Starting MCP3208\r\n");
goro56 0:709d290281a1 12 float Vref = 5.08;
goro56 0:709d290281a1 13 while(1)
goro56 0:709d290281a1 14 {
goro56 0:709d290281a1 15 cs = 0;
goro56 0:709d290281a1 16 uint8_t d0 = spi.write(0x06);
goro56 0:709d290281a1 17 uint8_t d1 = spi.write(0x40);
goro56 0:709d290281a1 18 uint8_t d2 = spi.write(0x00);
goro56 0:709d290281a1 19 printf("%d,%d,%d \r\n",d0,d1,d2);
goro56 0:709d290281a1 20 uint8_t d3 = d1 << 4;
goro56 0:709d290281a1 21 uint16_t d = (d3 << 4) | d2; // 1文にまとめると uint16_t d = (d1 << 8) | d2;
goro56 0:709d290281a1 22 //float volt = Vref * (float)d / 4096;
goro56 0:709d290281a1 23 //float amp = Vref * (float)d / 4096;
goro56 0:709d290281a1 24 //printf("d=%d volt=%5.2f\n\r", d, volt);
goro56 0:709d290281a1 25 //printf("d=%d CDH_Amp =%f [A]\n\r", d, amp);
goro56 0:709d290281a1 26
goro56 0:709d290281a1 27 //tem
goro56 0:709d290281a1 28
goro56 0:709d290281a1 29 float R3;
goro56 0:709d290281a1 30 float R4;
goro56 0:709d290281a1 31 float R5;
goro56 0:709d290281a1 32 float Pt;
goro56 0:709d290281a1 33 float R_1;
goro56 0:709d290281a1 34 float R_2;
goro56 0:709d290281a1 35 //current
goro56 0:709d290281a1 36 float I;
goro56 0:709d290281a1 37 //voltage
goro56 0:709d290281a1 38 float Vreft;
goro56 0:709d290281a1 39
goro56 0:709d290281a1 40 //temperature coefficient
goro56 0:709d290281a1 41 float ce;
goro56 0:709d290281a1 42 //resistance
goro56 0:709d290281a1 43 R3 = 110;//[Ω]
goro56 0:709d290281a1 44 R4 = 1000;//[Ω]
goro56 0:709d290281a1 45 R5 = 68000;//[Ω]
goro56 0:709d290281a1 46 Pt = 100;//[Ω]
goro56 0:709d290281a1 47 R_1 = 3;//[kΩ]
goro56 0:709d290281a1 48 R_2 = 2;//[kΩ]
goro56 0:709d290281a1 49
goro56 0:709d290281a1 50 //current
goro56 0:709d290281a1 51 I = 0.001;//[A]
goro56 0:709d290281a1 52
goro56 0:709d290281a1 53 //voltage
goro56 0:709d290281a1 54 Vreft = 2.5;//[V]
goro56 0:709d290281a1 55
goro56 0:709d290281a1 56 //Gain&Offset
goro56 0:709d290281a1 57 float gain = -R5*I/R4;
goro56 0:709d290281a1 58 float off = Vreft+I*R3;
goro56 0:709d290281a1 59
goro56 0:709d290281a1 60 //temperature coefficient
goro56 0:709d290281a1 61 ce = 0.003851;
goro56 0:709d290281a1 62
goro56 0:709d290281a1 63 float volt = Vref*(float)d / 4096*(R_1 + R_2)/R_1;
goro56 0:709d290281a1 64 float Rth = (volt-off)/gain+R3;
goro56 0:709d290281a1 65 float temp = (Rth-Pt)/(ce*Pt);
goro56 0:709d290281a1 66 printf("d=%d EPS_Temp =%f [℃]\n\r", d, temp);
goro56 0:709d290281a1 67
goro56 0:709d290281a1 68 cs = 1;
goro56 0:709d290281a1 69 wait(1.0);
goro56 0:709d290281a1 70 }
goro56 0:709d290281a1 71 }