Emulate inductor, its still not tuned properly

bugs/unimplementedHardware.txt

@@ -25,6 +25,7 @@ ICR POL(1,2,3,6) may flip the pin value as well as the interrupt, POL5 does not
 edge triggered INT* don't clear on write to ISR when masked in IMR(at least that seems to be the reason)
 if a sound interrupt is triggered while the button interrupt is disabled the button interrupt will still trigger(in galax game)
 PWM1 output value is not a direct range cast of 0<->255 to 0<->32767, its additive, see properPwmSineWave.png
+inductor dosent properly drain when PWM1 gets disabled
 
 Debug tools:
 ADS7846 channels can't be read in single reference mode in hwTestSuite

qtBuildSystem/Mu/Mu.pro

@@ -84,7 +84,8 @@ SOURCES += \
     src/pdiUsbD12.c \
     src/sdCard.c \
     src/sed1376.c \
-    src/silkscreen.c
+    src/silkscreen.c \
+    src/audio/inductor.c
 
 HEADERS += \
     src/audio/blip_buf.h \
@@ -117,7 +118,8 @@ HEADERS += \
     emuwrapper.h \
     mainwindow.h \
     statemanager.h \
-    touchscreen.h
+    touchscreen.h \
+    src/audio/inductor.h
 
 FORMS += \
     mainwindow.ui \

src/audio/inductor.c

@@ -0,0 +1,29 @@
+#include <stdint.h>
+#include <stdbool.h>
+
+#include "../portability.h"
+#include "../emulator.h"
+#include "blip_buf.h"
+
+
+#define INDUCTOR_RANGE 10000
+#define INDUCTOR_CLOCK_POWER 0.80
+
+
+int32_t inductorCurrentCharge;
+int32_t inductorLastAudioSample;
+
+
+void inductorReset(){
+   inductorCurrentCharge = 0;
+   inductorLastAudioSample = 0;
+}
+
+void inductorAddClocks(int32_t clocks, bool charge){
+   inductorCurrentCharge = sClamp(-INDUCTOR_RANGE, inductorCurrentCharge + (charge ? +clocks : -clocks) * INDUCTOR_CLOCK_POWER, INDUCTOR_RANGE);
+}
+
+void inductorSampleAudio(int32_t now){
+   blip_add_delta(palmAudioResampler, now, inductorCurrentCharge - inductorLastAudioSample);
+   inductorLastAudioSample = inductorCurrentCharge;
+}

src/audio/inductor.h

@@ -0,0 +1,12 @@
+#pragma once
+
+#include <stdint.h>
+#include <stdbool.h>
+
+extern int32_t inductorCurrentCharge;
+extern int32_t inductorLastAudioSample;
+
+void inductorReset();
+
+void inductorAddClocks(int32_t clocks, bool charge);
+void inductorSampleAudio(int32_t now);

src/emulator.c

@@ -5,6 +5,7 @@
 
 #include "m68k/m68k.h"
 #include "audio/blip_buf.h"
+#include "audio/inductor.h"
 #include "m68328.h"
 #include "emulator.h"
 #include "hardwareRegisters.h"
@@ -107,6 +108,7 @@ uint32_t emulatorInit(buffer_t palmRomDump, buffer_t palmBootDump, uint32_t spec
    sed1376Reset();
    ads7846Reset();
    pdiUsbD12Reset();
+   inductorReset();
    sandboxInit();
 
    memset(&palmInput, 0x00, sizeof(palmInput));
@@ -144,11 +146,11 @@ void emulatorExit(){
 void emulatorReset(){
    //reset doesnt clear RAM or SD card, all programs are stored in RAM or on SD card
    debugLog("Reset triggered, PC:0x%08X\n", m68k_get_reg(NULL, M68K_REG_PPC));
-   blip_add_delta(palmAudioResampler, 0, -pwm1LastSampleDelta);
    m68328Reset();
    sed1376Reset();
    ads7846Reset();
    pdiUsbD12Reset();
+   inductorReset();
 }
 
 void emulatorSetRtc(uint16_t days, uint8_t hours, uint8_t minutes, uint8_t seconds){
@@ -186,7 +188,7 @@ uint64_t emulatorGetStateSize(){
    size += sizeof(int32_t);//pwm1ClocksToNextSample
    size += sizeof(uint8_t) * 6;//pwm1Fifo[6]
    size += sizeof(uint8_t) * 2;//pwm1(Read/Write)
-   size += sizeof(int32_t);//pwm1LastSampleDelta
+   size += sizeof(int32_t) * 2;//inductorCurrentCharge / inductorLastAudioSample
    size += sizeof(uint8_t) * 7;//palmMisc
    size += sizeof(uint32_t);//palmSdCard.command
    size += sizeof(uint8_t) * 2;//palmSdCard.response / palmSdCard.commandBitsRemaining
@@ -311,7 +313,9 @@ bool emulatorSaveState(buffer_t buffer){
    offset += sizeof(uint8_t);
    writeStateValueUint8(buffer.data + offset, pwm1WritePosition);
    offset += sizeof(uint8_t);
-   writeStateValueInt32(buffer.data + offset, pwm1LastSampleDelta);
+   writeStateValueInt32(buffer.data + offset, inductorCurrentCharge);
+   offset += sizeof(int32_t);
+   writeStateValueInt32(buffer.data + offset, inductorLastAudioSample);
    offset += sizeof(int32_t);
 
    //misc
@@ -462,10 +466,10 @@ bool emulatorLoadState(buffer_t buffer){
    offset += sizeof(uint8_t);
    pwm1WritePosition = readStateValueUint8(buffer.data + offset);
    offset += sizeof(uint8_t);
-   blip_add_delta(palmAudioResampler, 0, -pwm1LastSampleDelta);
-   pwm1LastSampleDelta = readStateValueInt32(buffer.data + offset);
+   inductorCurrentCharge = readStateValueInt32(buffer.data + offset);
+   offset += sizeof(int32_t);
+   inductorLastAudioSample = readStateValueInt32(buffer.data + offset);
    offset += sizeof(int32_t);
-   blip_add_delta(palmAudioResampler, 0, pwm1LastSampleDelta);
 
    //misc
    palmMisc.powerButtonLed = readStateValueBool(buffer.data + offset);

src/emulator.h

@@ -120,7 +120,7 @@ typedef struct{
 
 //system constants
 #define CRYSTAL_FREQUENCY 32768
-#define AUDIO_AMPLITUDE 1000000
+#define AUDIO_VOLUME 10//1000000
 #define AUDIO_SAMPLES_PER_FRAME (AUDIO_SAMPLE_RATE / EMU_FPS)
 #define AUDIO_END_OF_FRAME (235929600 / EMU_FPS)//smallest amount of time a second can be split into:(2.0 * (14.0 * (255 + 1.0) + 15 + 1.0)) * 32768 == 235929600, used to convert the variable timing of SYSCLK and CLK32 to a fixed location in the current frame 0<->AUDIO_END_OF_FRAME
 #define AUDIO_WAIT_FOR_SAMPLE INT32_MIN

src/hardwareRegisters.c

@@ -34,7 +34,6 @@ int32_t  pwm1ClocksToNextSample;
 uint8_t  pwm1Fifo[6];
 uint8_t  pwm1ReadPosition;
 uint8_t  pwm1WritePosition;
-int32_t  pwm1LastSampleDelta;
 
 
 static void checkInterrupts();
@@ -1083,7 +1082,6 @@ void resetHwRegisters(){
    memset(pwm1Fifo, 0x00, sizeof(pwm1Fifo));
    pwm1ReadPosition = 0;
    pwm1WritePosition = 0;
-   pwm1LastSampleDelta = 0;
 
    memset(chips, 0x00, sizeof(chips));
    //all chip selects are disabled at boot and CSA0 is mapped to 0x00000000 and covers the entire address range until CSA is set enabled

src/hardwareRegisters.h

@@ -80,7 +80,6 @@ extern int32_t  pwm1ClocksToNextSample;
 extern uint8_t  pwm1Fifo[];
 extern uint8_t  pwm1ReadPosition;
 extern uint8_t  pwm1WritePosition;
-extern int32_t  pwm1LastSampleDelta;
 
 //timing
 void beginClk32();

src/hardwareRegistersAccessors.c.h

@@ -85,12 +85,18 @@ int32_t pwm1FifoRunSample(int32_t now, int32_t clockOffset){
    uint8_t prescaler = (pwmc1 >> 8 & 0x7F) + 1;
    uint8_t clockDivider = 2 << (pwmc1 & 0x03);
    uint8_t repeat = 1 << (pwmc1 >> 2 & 0x03);
-   int32_t audioStart = now + clockOffset;
-   int32_t audioSampleDuration = usingClk32 ? audioGetFramePercentIncrementFromClk32s(period * prescaler * clockDivider * repeat) : audioGetFramePercentIncrementFromSysclks(period * prescaler * clockDivider * repeat);
-   int32_t audioDeew = dMin((double)sample / period, 1.0)/*dutyCycle*/ * AUDIO_AMPLITUDE;
+   int32_t audioNow = now + clockOffset;
+   int32_t audioSampleDuration = usingClk32 ? audioGetFramePercentIncrementFromClk32s(period * prescaler * clockDivider) : audioGetFramePercentIncrementFromSysclks(period * prescaler * clockDivider);
+   int32_t audioDutyCycle = dMin((double)sample / period, 1.0)/*dutyCycle*/ * audioSampleDuration;
 
-   blip_add_delta(palmAudioResampler, audioStart, audioDeew - pwm1LastSampleDelta);
-   pwm1LastSampleDelta = audioDeew;
+   //relay all the samples to the inductor
+   for(uint8_t index = 0; index < repeat; index++){
+      inductorAddClocks(audioDutyCycle, true);
+      inductorSampleAudio(audioNow + audioDutyCycle);
+      inductorAddClocks(audioSampleDuration - audioDutyCycle, false);
+      inductorSampleAudio(audioNow + audioSampleDuration);
+      audioNow += audioSampleDuration;
+   }
 
    //remove used entry
    if(pwm1FifoEntrys() > 0)
@@ -106,12 +112,7 @@ int32_t pwm1FifoRunSample(int32_t now, int32_t clockOffset){
       registerArrayWrite16(PWMC1, pwmc1 | 0x0080);//set IRQ bit
    }
 
-   return audioSampleDuration;
-}
-
-static inline void pwm1FifoFinished(int32_t now){
-   blip_add_delta(palmAudioResampler, now, -pwm1LastSampleDelta);
-   pwm1LastSampleDelta = 0;
+   return audioSampleDuration * repeat;
 }
 
 static inline void pwm1FifoWrite(uint8_t value){
@@ -619,18 +620,23 @@ static inline uint8_t getPortMValue(){
 static inline void samplePwm1(bool forClk32, double sysclks){
    //clear PWM1 FIFO values if enough time has passed
    uint16_t pwmc1 = registerArrayRead16(PWMC1);
+   int32_t audioClocks;
 
    //check if enabled and validate clock mode
    if(!(pwmc1 & 0x0010) || forClk32 != (bool)(pwmc1 & 0x8000))
       return;
 
+   //this calculation is fairly heavy, only do it after we know the clock mode is valid
+   audioClocks = forClk32 ? audioGetFramePercentIncrementFromClk32s(1) : audioGetFramePercentIncrementFromSysclks(sysclks);
+
    //add cycles
    if(pwm1ClocksToNextSample != AUDIO_WAIT_FOR_SAMPLE)
-      pwm1ClocksToNextSample -= forClk32 ? audioGetFramePercentIncrementFromClk32s(1) : audioGetFramePercentIncrementFromSysclks(sysclks);
+      pwm1ClocksToNextSample -= audioClocks;
 
    //use samples
    if(pwm1ClocksToNextSample <= 0){
       int32_t audioNow = audioGetFramePercentage();
+      int32_t audioClocksLeft = audioClocks;
 
       while(pwm1FifoEntrys() > 0 && pwm1ClocksToNextSample <= 0){
          int32_t audioUsed;
@@ -648,12 +654,17 @@ static inline void samplePwm1(bool forClk32, double sysclks){
          }
 
          audioNow += audioUsed;
+         audioClocksLeft -= audioUsed;//goes negative when extra clocks are used
       }
 
       //all samples used and its still negative, wait for next sample
-      if(pwm1ClocksToNextSample != AUDIO_WAIT_FOR_SAMPLE && pwm1ClocksToNextSample <= 0){
-         pwm1FifoFinished(audioNow);
+      if(pwm1ClocksToNextSample <= 0)
          pwm1ClocksToNextSample = AUDIO_WAIT_FOR_SAMPLE;
+
+      //add 0 cycles to inductor when theres no samples
+      if(audioClocksLeft > 0){
+         inductorAddClocks(audioClocksLeft, false);
+         inductorSampleAudio(audioNow + audioClocksLeft);
       }
    }
 }

src/makefile.all

@@ -14,4 +14,5 @@ EMU_SOURCES_C := $(EMU_PATH)/emulator.c \
       $(EMU_PATH)/m68k/m68kdasm.c \
       $(EMU_PATH)/m68k/m68kcpu.c \
       $(EMU_PATH)/audio/blip_buf.c \
+      $(EMU_PATH)/audio/inductor.c \
       $(EMU_PATH)/debug/sandbox.c