CSUSM FM Synth 2017 / Mbed 2 deprecated FMSynthCSUSM

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Dependencies:   mbed

Fork of STM32FMSynth by Steven Clark

main.cpp@7:b0cd74923bc6, 2017-12-06 (annotated)

Committer:
davolfman
Date:
Wed Dec 06 22:33:04 2017 +0000
Revision:
7:b0cd74923bc6
Parent:
6:9f8c8c3c111d
Child:
8:13b0594510de
compiles at least

Who changed what in which revision?

UserRevisionLine numberNew contents of line
davolfman 0:b2f7400596ce 1 #include "mbed.h"
davolfman 3:83ac767f3a63 2 #include "sintable.h"
davolfman 0:b2f7400596ce 3
davolfman 0:b2f7400596ce 4 AnalogOut DAC0(PA_4);//Not labeled in the docs for the f401, but seems to be for all
davolfman 7:b0cd74923bc6 5 //AnalogOut DAC1(PA_5);
davolfman 0:b2f7400596ce 6
davolfman 0:b2f7400596ce 7 AnalogIn ADC0(PA_0);
davolfman 7:b0cd74923bc6 8 AnalogIn inModAmt(PA_1);
davolfman 6:9f8c8c3c111d 9 //AnalogIn ADC2(PA_2);//these are the uart pins!!
davolfman 6:9f8c8c3c111d 10 //AnalogIn ADC3(PA_3);//these are the uart pins!!
davolfman 0:b2f7400596ce 11 //AnalogIn ADC4(PA_4);//we're using these for output
davolfman 0:b2f7400596ce 12 //AnalogIn ADC5(PA_5);//we're using these for output
davolfman 0:b2f7400596ce 13 AnalogIn ADC6(PA_6);
davolfman 0:b2f7400596ce 14 AnalogIn ADC7(PA_7);
davolfman 0:b2f7400596ce 15 //AnalogIn ADC8(PB_0);//lets leave the 2 we aren't using in a single port
davolfman 0:b2f7400596ce 16 //AnalogIn ADC9(PB_1);//that way we know there's not ADCs on one of them
davolfman 0:b2f7400596ce 17 AnalogIn ADC10(PC_0);
davolfman 0:b2f7400596ce 18 AnalogIn ADC11(PC_1);
davolfman 0:b2f7400596ce 19 AnalogIn ADC12(PC_2);
davolfman 0:b2f7400596ce 20 AnalogIn ADC13(PC_3);
davolfman 0:b2f7400596ce 21 AnalogIn ADC14(PC_4);
davolfman 0:b2f7400596ce 22 AnalogIn ADC15(PC_5);
davolfman 0:b2f7400596ce 23
davolfman 2:5454dee210ed 24 BusIn keyBank(PC_10, PC_11, PC_12, PC_13, PC_14, PC_15);
davolfman 7:b0cd74923bc6 25 BusOut bankSelect(PB_0, PB_1, PB_2, PB_3, PB_4, PB_5, PB_6, PB_7, PB_8);
davolfman 2:5454dee210ed 26 BusIn numerator(PA_8, PA_9, PA_10, PA_11);
davolfman 2:5454dee210ed 27 BusIn denominator(PA_12, PA_13, PA_14, PA_15);
davolfman 2:5454dee210ed 28
davolfman 0:b2f7400596ce 29 //Renaming ports
davolfman 0:b2f7400596ce 30 #define inVol ADC0
davolfman 7:b0cd74923bc6 31 //#define inModAmt ADC1
davolfman 0:b2f7400596ce 32 #define inCarA ADC6
davolfman 0:b2f7400596ce 33 #define inCarD ADC7
davolfman 0:b2f7400596ce 34 #define inCarS ADC10
davolfman 0:b2f7400596ce 35 #define inCarR ADC11
davolfman 0:b2f7400596ce 36 #define inModA ADC12
davolfman 0:b2f7400596ce 37 #define inModD ADC13
davolfman 0:b2f7400596ce 38 #define inModS ADC14
davolfman 0:b2f7400596ce 39 #define inModR ADC15
davolfman 0:b2f7400596ce 40 #define outMono DAC0
davolfman 0:b2f7400596ce 41
davolfman 2:5454dee210ed 42 #define numKeys 49
davolfman 1:f3350a372732 43 #define PI M_PI
davolfman 0:b2f7400596ce 44
davolfman 4:1d2a699c95c7 45 //constants
davolfman 4:1d2a699c95c7 46 const int carrierIncrements[] = {107, 113, 120, 127, 135, 143, 151, 160, 170,
davolfman 4:1d2a699c95c7 47 180, 190, 202, 214, 227, 240, 254, 270, 286, 303, 321, 340, 360, 381, 404,
davolfman 4:1d2a699c95c7 48 428, 454, 481, 509, 540, 572, 606, 642, 680, 720, 763, 809, 857, 908, 962,
davolfman 4:1d2a699c95c7 49 1019, 1080, 1144, 1212, 1284, 1360, 1441, 1527, 1618, 1714};
davolfman 1:f3350a372732 50 const int attackLimit = (0x1 << 16) - 1;
davolfman 7:b0cd74923bc6 51 #define U_PI 3.14159265358979f
davolfman 7:b0cd74923bc6 52 const int fixed2pi = (int) ((2.0 * U_PI) * (0x1 << 16));
davolfman 1:f3350a372732 53
davolfman 0:b2f7400596ce 54 //non-constants
davolfman 1:f3350a372732 55 //Most of these will be recalculated or reset on every input cycle of the main
davolfman 1:f3350a372732 56 // loop, as appropriate
davolfman 0:b2f7400596ce 57 int FMmult;
davolfman 0:b2f7400596ce 58 int Volume;
davolfman 1:f3350a372732 59 int modVol;
davolfman 1:f3350a372732 60 int modAmpI;
davolfman 1:f3350a372732 61 int carAmpS;
davolfman 2:5454dee210ed 62 //bool keysPressed[numKeys];
davolfman 2:5454dee210ed 63 int64_t keyboard;
davolfman 0:b2f7400596ce 64 int carrierPhases[numKeys];
davolfman 0:b2f7400596ce 65 int modulatorPhases[numKeys];
davolfman 0:b2f7400596ce 66 short envelopeStatesC[numKeys];
davolfman 0:b2f7400596ce 67 short envelopeStatesM[numKeys];
davolfman 0:b2f7400596ce 68 int envelopeAmpsC[numKeys];
davolfman 1:f3350a372732 69 int envelopeAmpsM[numKeys];
davolfman 1:f3350a372732 70
davolfman 1:f3350a372732 71 int modA;
davolfman 1:f3350a372732 72 int modD;
davolfman 1:f3350a372732 73 int modS;
davolfman 1:f3350a372732 74 int modR;
davolfman 1:f3350a372732 75 int carA;
davolfman 1:f3350a372732 76 int carD;
davolfman 1:f3350a372732 77 int carS;
davolfman 1:f3350a372732 78 int carR;
davolfman 1:f3350a372732 79
davolfman 1:f3350a372732 80 int fastSin(const int phase){
davolfman 5:ac5c4bd3ef4b 81 int index = (phase & 0x3ffc) >> 2;
davolfman 5:ac5c4bd3ef4b 82 int subindex = phase & 0x3;
davolfman 5:ac5c4bd3ef4b 83 int quadrant = (phase & 0xc000) >> 14;
davolfman 3:83ac767f3a63 84 int sum = 0;
davolfman 5:ac5c4bd3ef4b 85 switch (quadrant) {
davolfman 5:ac5c4bd3ef4b 86 case 0:
davolfman 7:b0cd74923bc6 87 sum += (4 - subindex) * sinTable[index];
davolfman 7:b0cd74923bc6 88 sum += subindex * sinTable[index+1];
davolfman 5:ac5c4bd3ef4b 89 break;
davolfman 5:ac5c4bd3ef4b 90 case 1:
davolfman 7:b0cd74923bc6 91 sum += (4 - subindex) * sinTable[1+4095-index];
davolfman 7:b0cd74923bc6 92 sum += subindex * sinTable[4095-index];
davolfman 5:ac5c4bd3ef4b 93 break;
davolfman 5:ac5c4bd3ef4b 94 case 2:
davolfman 7:b0cd74923bc6 95 sum -= (4 - subindex) * sinTable[index];
davolfman 7:b0cd74923bc6 96 sum -= subindex * sinTable[index+1];
davolfman 5:ac5c4bd3ef4b 97 break;
davolfman 5:ac5c4bd3ef4b 98 case 3:
davolfman 7:b0cd74923bc6 99 sum -= (4 - subindex) * sinTable[1+4095-index];
davolfman 7:b0cd74923bc6 100 sum -= subindex * sinTable[4095-index];
davolfman 5:ac5c4bd3ef4b 101 break;
davolfman 5:ac5c4bd3ef4b 102 }
davolfman 3:83ac767f3a63 103 sum = sum >> 2;
davolfman 3:83ac767f3a63 104
davolfman 3:83ac767f3a63 105 return sum;
davolfman 1:f3350a372732 106 }
davolfman 0:b2f7400596ce 107
davolfman 1:f3350a372732 108 void synthesize(){
davolfman 1:f3350a372732 109 carAmpS = 0;
davolfman 1:f3350a372732 110 for(int i = 0; i < numKeys; ++i){
davolfman 2:5454dee210ed 111 if(keyboard & (0x1 << i)){
davolfman 1:f3350a372732 112 if(envelopeStatesC[i] < 2)
davolfman 1:f3350a372732 113 envelopeStatesC[i] = 4;
davolfman 1:f3350a372732 114 if(envelopeStatesM[i] < 2)
davolfman 1:f3350a372732 115 envelopeStatesM[i] = 4;
davolfman 1:f3350a372732 116
davolfman 1:f3350a372732 117 if(envelopeStatesC[i] == 4){
davolfman 1:f3350a372732 118 envelopeAmpsC[i] += carA;
davolfman 1:f3350a372732 119 if(envelopeAmpsC[i] >= attackLimit){
davolfman 1:f3350a372732 120 envelopeAmpsC[i] = attackLimit;
davolfman 1:f3350a372732 121 envelopeStatesC[i] = 3;
davolfman 1:f3350a372732 122 }
davolfman 1:f3350a372732 123 }
davolfman 1:f3350a372732 124
davolfman 1:f3350a372732 125 if(envelopeStatesM[i] == 4){
davolfman 1:f3350a372732 126 envelopeAmpsM[i] += modA;
davolfman 1:f3350a372732 127 if(envelopeAmpsM[i] >= attackLimit){
davolfman 1:f3350a372732 128 envelopeAmpsM[i] = attackLimit;
davolfman 1:f3350a372732 129 envelopeStatesM[i] = 3;
davolfman 1:f3350a372732 130 }
davolfman 1:f3350a372732 131 }
davolfman 1:f3350a372732 132
davolfman 1:f3350a372732 133 if(envelopeStatesC[i] == 3){
davolfman 1:f3350a372732 134 envelopeAmpsC[i] += carD;
davolfman 1:f3350a372732 135 if(envelopeAmpsC[i] <= carS){
davolfman 1:f3350a372732 136 envelopeAmpsC[i] = carS;
davolfman 1:f3350a372732 137 envelopeStatesC[i] = 2;
davolfman 1:f3350a372732 138 }
davolfman 1:f3350a372732 139 }
davolfman 1:f3350a372732 140
davolfman 1:f3350a372732 141 if(envelopeStatesM[i] == 3){
davolfman 1:f3350a372732 142 envelopeAmpsM[i] += modD;
davolfman 1:f3350a372732 143 if(envelopeAmpsM[i] <= modS){
davolfman 1:f3350a372732 144 envelopeAmpsM[i] = modS;
davolfman 1:f3350a372732 145 envelopeStatesM[i] = 2;
davolfman 1:f3350a372732 146 }
davolfman 1:f3350a372732 147 }
davolfman 1:f3350a372732 148 }else{
davolfman 1:f3350a372732 149 if(envelopeStatesC[i] > 1)
davolfman 1:f3350a372732 150 envelopeStatesC[i] = 1;
davolfman 1:f3350a372732 151 if(envelopeStatesM[i] > 1)
davolfman 1:f3350a372732 152 envelopeStatesM[i] = 1;
davolfman 1:f3350a372732 153
davolfman 1:f3350a372732 154 if(envelopeStatesC[i] == 1){
davolfman 1:f3350a372732 155 if(envelopeAmpsC[i] <= 0){
davolfman 1:f3350a372732 156 envelopeStatesC[i] = 0;
davolfman 1:f3350a372732 157 envelopeAmpsC[i] = 0;
davolfman 1:f3350a372732 158 }else{
davolfman 1:f3350a372732 159 envelopeAmpsC[i] -= carR;
davolfman 1:f3350a372732 160 }
davolfman 1:f3350a372732 161 }
davolfman 1:f3350a372732 162 if(envelopeStatesM[i] == 1){
davolfman 1:f3350a372732 163 if(envelopeAmpsM[i] <= 0){
davolfman 1:f3350a372732 164 envelopeStatesM[i] = 0;
davolfman 1:f3350a372732 165 envelopeAmpsM[i] = 0;
davolfman 1:f3350a372732 166 }else{
davolfman 1:f3350a372732 167 envelopeAmpsM[i] -= modR;
davolfman 1:f3350a372732 168 }
davolfman 1:f3350a372732 169 }
davolfman 1:f3350a372732 170 }
davolfman 1:f3350a372732 171
davolfman 1:f3350a372732 172 if(envelopeAmpsC[i] > 0){
davolfman 7:b0cd74923bc6 173 modulatorPhases[i] += (FMmult * carrierIncrements[i]) >> 16;
davolfman 1:f3350a372732 174 modAmpI = fastSin((((modulatorPhases[i] * envelopeAmpsM[i]) >> 16)
davolfman 1:f3350a372732 175 * modVol) >> 16);
davolfman 1:f3350a372732 176 carrierPhases[i] += ((carrierIncrements[i] + modAmpI) * fixed2pi) >> 16;
davolfman 7:b0cd74923bc6 177 carAmpS += (fastSin(carrierPhases[i]) * envelopeAmpsC[i]) >> 16;
davolfman 1:f3350a372732 178 }
davolfman 1:f3350a372732 179 }
davolfman 7:b0cd74923bc6 180 outMono.write_u16(((carAmpS / numKeys) * Volume) >> 16);
davolfman 1:f3350a372732 181 }
davolfman 0:b2f7400596ce 182
davolfman 0:b2f7400596ce 183
davolfman 0:b2f7400596ce 184 int main() {
davolfman 2:5454dee210ed 185 int ratNumer;
davolfman 2:5454dee210ed 186 int ratDenom;
davolfman 2:5454dee210ed 187
davolfman 2:5454dee210ed 188 while(true){
davolfman 2:5454dee210ed 189 ratNumer = 0xf & ~ numerator;
davolfman 7:b0cd74923bc6 190 ratDenom = 0xf & ~ denominator;
davolfman 7:b0cd74923bc6 191 FMmult = (ratNumer << 16) / ratDenom;
davolfman 2:5454dee210ed 192
davolfman 2:5454dee210ed 193 Volume = (int)inVol.read_u16();
davolfman 2:5454dee210ed 194 modVol = (int)inModAmt.read_u16();
davolfman 2:5454dee210ed 195
davolfman 2:5454dee210ed 196 carA = 0xffff / ((int)inCarA.read_u16());
davolfman 2:5454dee210ed 197 carD = 0xffff / ((int)inCarD.read_u16());
davolfman 2:5454dee210ed 198 carS = (int)inCarS.read_u16();
davolfman 2:5454dee210ed 199 carR = 0xffff / ((int)inCarR.read_u16());
davolfman 2:5454dee210ed 200
davolfman 2:5454dee210ed 201 modA = 0xffff / ((int)inModA.read_u16());
davolfman 2:5454dee210ed 202 modD = 0xffff / ((int)inModD.read_u16());
davolfman 2:5454dee210ed 203 modS = (int)inModS.read_u16();
davolfman 2:5454dee210ed 204 modR = 0xffff / ((int)inModR.read_u16());
davolfman 2:5454dee210ed 205
davolfman 7:b0cd74923bc6 206 //THIS IS CORRECT (1 means the key is connected)
davolfman 7:b0cd74923bc6 207 // B8 B7 B6 B5 B4 B3 B2 B1 B0
davolfman 7:b0cd74923bc6 208 // |----||----||----||----||----||----||----||----||
davolfman 7:b0cd74923bc6 209 //0000000000000001111111111111111111111111111111111111111111111111
davolfman 7:b0cd74923bc6 210 //
davolfman 7:b0cd74923bc6 211 //THIS IS NOT CORRECT (1 means the key is connected)
davolfman 7:b0cd74923bc6 212 // B8 B7 B6 B5 B4 B3 B2 B1 B0
davolfman 7:b0cd74923bc6 213 // |----||----||----||----||----||----||----||----||----|
davolfman 7:b0cd74923bc6 214 //0000000000111111111111111111111111111111111111111111111111000001
davolfman 7:b0cd74923bc6 215 //Thus, we need to subtract 5 from our shift for every bank > 0
davolfman 7:b0cd74923bc6 216 //'keyboard' should be uint64_t and not int64_t b/c keyboard&=~62 will make it negative, which isn't a huge deal really
davolfman 7:b0cd74923bc6 217 keyboard = 0; //zero the keys before we start ORing on top of everything
davolfman 7:b0cd74923bc6 218 for(int i = 0; i < 9; ++i) { //removed <= 9 because there is not 10 banks
davolfman 7:b0cd74923bc6 219 bankSelect = (short)(~(1 << i)) & bankSelect.mask();
davolfman 7:b0cd74923bc6 220
davolfman 7:b0cd74923bc6 221 int shiftOffset = 6 * i;
davolfman 7:b0cd74923bc6 222 if(i > 0) shiftOffset -= 5; //bank 0 only has 1 key, so to prevent 5 missing keys and bits we subtract 5 for every bank > 0
davolfman 7:b0cd74923bc6 223 else keyboard &= ~62; //clear bits 1-5 (xx00000x) b/c we are ORing the next bank of keys on top of them & they may not be 0
davolfman 7:b0cd74923bc6 224
davolfman 7:b0cd74923bc6 225 keyboard |= ((~keyBank) & keyBank.mask()) << shiftOffset;
davolfman 7:b0cd74923bc6 226 }
davolfman 2:5454dee210ed 227 }
davolfman 0:b2f7400596ce 228 }