MSP430中利用SD16模块进行AD转换

//***************************************************************************** // MSP-FET430P410 Demo - SD16, Single Conversion on a Group of Channels // // Description: This program uses the SD16 module to perform a single // conversion on a group of channels (0, 1, and 2). A SD16 interrupt occurs // when the conversions have completed. Test by applying voltages to the // three input channels and setting a breakpoint at the line indicated // below. Run program until it reaches the breakpoint, then use the // debugger's watch window to view the conversion results. Results for all // three channels are stored in the array "results". NOTE: array won't // contain values until after reaching breakpoint for the second time. // ACLK = LFXT1 = 32768 Hz, MCLK = SMCLK = DCO = 32 x ACLK = 1048576 Hz // //* An external watch crystal on XIN XOUT is required for ACLK *// // //* Minimum Vcc is required for SD16 module - see datasheet *// // //* 100nF cap btw Vref and AVss is recommended when using 1.2V ref *// // // MSP430F427 // ----------------- // /|\| XIN|- // | | | 32kHz // --|RST XOUT|- // | | // Vin1+ -->|A0.0+ | // Vin1- -->|A0.0- | // Vin2+ -->|A1.0+ | // Vin2- -->|A1.0- | // Vin3+ -->|A2.0+ | // Vin3- -->|A2.0- | // | | // | VREF |---+ // | | | // | | -+- 100nF // | | -+- // | | | // | AVss |---+ // | | // // H. Grewal // Texas Instruments Inc. // Feb 2005 // Built with IAR Embedded Workbench Version: 3.21A //***************************************************************************** #include <msp430x42x.h> /* Array to store SD16 conversion results */ /* NOTE: array needs to be global to */ /* prevent removal by compiler */ static unsigned int results[3]; float vt1,vt0,pr1,pr0,temperature1,temperature0; static float pt1000[202]={1000,1001.954,1003.908,1005.861,1007.814,1009.767,1011.72,1013.672,1015.624,1017.576, 1019.527,1021.478,1023.429,1025.38,1027.33,1029.28,1031.229,1033.179,1035.128,1037.077, 1039.025,1040.973,1042.921,1044.869,1046.816,1048.764,1050.71,1052.657,1054.603,1056.549, 1058.495,1060.44,1062.385,1064.33,1066.274,1068.218,1070.162,1072.106,1074.049,1075.992, 1077.935,1079.877,1081.82,1083.762,1085.703,1087.644,1089.585,1091.526,1093.467,1095.407, 1097.347,1099.286,1101.225,1103.164,1105.103,1107.042,1108.98,1110.917,1112.855,1114.792, 1116.729,1118.666,1120.602,1122.538,1124.474,1126.41,1128.345,1130.28,1132.215,1134.149, 1136.083,1138.017,1139.95,1141.884,1143.817,1145.749,1147.681,1149.614,1151.545,1153.477, 1155.408,1157.339,1159.27,1161.2,1163.13,1165.06,1166.989,1168.918,1170.847,1172.776, 1174.704,1176.632,1178.56,1180.487,1182.414,1184.341,1186.268,1188.194,1190.12,1192.046, 1193.971,1195.896,1197.821,1199.746,1201.67,1203.594,1205.518,1207.441,1209.364,1211.287, 1213.21,1215.12,1217.054,1218.975,1220.897,1222.818,1224.739,1226.659,1228.579,1230.499, 1232.419,1234.338,1236.257,1238.176,1240.095,1242.03,1243.931,1245.848,1247.766,1249.683, 1251.6,1253.516,1255.432,1257.348,1259.264,1261.179,1263.094,1265.009,1266.923,1268.837, 1270.751,1272.665,1274.578,1275.141,1278.404,1280.316,1282.228,1284.14,1286.052,1287.963, 1289.874,1291.785,1293.695,1295.605,1297.515,1299.425,1301.334,1303.243,1305.152,1307.06, 1308.968,1310.876,1312.783,1314.691,1316.597,1318.504,1320.411,1322.316,1324.222,1326.128, 1328.033,1329.938,1331.843,1333.747,1335.651,1337.555,1339.458,1321.361,1343.264,1345.167, 1347.069,1348.971,1350.873,1352.774,1354.676,1356.577,1358.477,1360.377,1362.277,1364.177, 1366.077,1367.976,1369.875,1371.773,1373.671,1375.569,1377.467,1379.365,1381.262,1383.158, 1385.055,1386.951}; void main(void) { volatile unsigned int i; // Use volatile to prevent removal // by compiler optimization WDTCTL = WDTPW + WDTHOLD; // Stop WDT FLL_CTL0 |= XCAP14PF; // Configure load caps for (i = 0; i < 10000; i++); // Delay for 32 kHz crystal to // stabilize SD16CTL = SD16REFON+SD16SSEL0+SD16VMIDON; // 1.2V ref, SMCLK SD16CCTL0 = SD16SNGL+SD16GRP; // Single conv, group with CH1 SD16CCTL1 = SD16SNGL+SD16GRP; // Single conv, group with CH2 SD16CCTL2 = SD16SNGL+SD16IE; // Single conv, enable interrupt for (i = 0; i < 0x3600; i++); // Delay for 1.2V ref startup _EINT(); // Enable general interrupts while (1) { SD16CCTL2 |= SD16SC; // SET BREAKPOINT HERE // Set bit to start conversion /* //test i=100; pr0=pt1000[i];*/ _BIS_SR(LPM0_bits); // Enter LPM0 } } #pragma vector=SD16_VECTOR __interrupt void SD16ISR(void) { float mid_num; unsigned char i; switch (SD16IV) { case 2: // SD16MEM Overflow break; case 4: // SD16MEM0 IFG break; case 6: // SD16MEM1 IFG break; case 8: // SD16MEM2 IFG results[0] = SD16MEM0; // Save CH0 results (clears IFG) results[1] = SD16MEM1; // Save CH1 results (clears IFG) results[2] = SD16MEM2; // Save CH2 results (clears IFG) //vt1=(float)(results[1]+40)/65536*1.2-0.6; //vt0=(float)(results[0]+40)/65536*1.2-0.6; //pr1=1508.1*vt1/(1.2-vt1); //pr0=1495*vt0/(1.2-vt0); pr1=(results[1]-32768)*1515.0/(98304-results[1]); pr0=(results[0]-32768)*1501.8/(98304-results[0]); if(pr1>1174.704){//高于45度时的处理 pr1=(results[1]-32768)*1511.6/(98304-results[1]); } if(pr0>1174.704){ pr0=(results[0]-32768)*1499.4/(98304-results[0]); } if(pr1<1039.025){//低于10度时的处理 pr1=(results[1]-32768)*1525.3/(98304-results[1]); } if(pr0<1039.025){ pr0=(results[0]-32768)*1513.8/(98304-results[0]); } if(1039.025<pr0<1077.935){ pr0=(results[0]-32768)*1504.6/(98304-results[0]); } if(1039.025<pr1<1077.935){ pr1=(results[1]-32768)*1516.9/(98304-results[1]); } break; } for(i=0;i<=201;i++){ if(pr1<pt1000[i]){ mid_num=(pt1000[i]+pt1000[i-1])/2; if(pr1<mid_num) temperature1=0.5*(i-1); else temperature1=0.5*i; break; } } for(i=0;i<=201;i++){ if(pr0<pt1000[i]){ mid_num=(pt1000[i]+pt1000[i-1])/2; if(pr0<mid_num) temperature0=0.5*(i-1); else temperature0=0.5*i; break; } } _BIC_SR_IRQ(LPM0_bits); // Exit LPM0 }