Experiments with nuked-opl3

sw/CMakeLists.txt

@@ -89,26 +89,30 @@ if(PROJECT_TYPE STREQUAL "GUS")
         )
         pico_enable_stdio_uart(picogus 0)
     else()
-        pico_enable_stdio_uart(picogus 1)
+        pico_enable_stdio_uart(picogus 0)
     endif()
-    pico_enable_stdio_usb(picogus 0)
+    pico_enable_stdio_usb(picogus 1)
     pico_enable_stdio_semihosting(picogus 0)
 endif()
 
 if(PROJECT_TYPE STREQUAL "OPL")
     pico_set_program_name(picogus "picogus-adlib")
-    target_sources(picogus PRIVATE adlibplay.cpp)
+    target_sources(picogus PRIVATE
+        adlibplay.cpp
+        Nuked-OPL3/opl3.c
+    )
     target_link_libraries(
         picogus
-        opl
+        # opl
     )
     target_compile_definitions(picogus PRIVATE
         SOUND_OPL=1
-        USE_EMU8950_OPL=1
-        EMU8950_ASM=1
+        # USE_EMU8950_OPL=1
+        # EMU8950_ASM=1
+        OPL_NUKED=1
     )
-    add_subdirectory(opl)
-    pico_enable_stdio_uart(picogus 0)
+    # add_subdirectory(opl)
+    pico_enable_stdio_uart(picogus 1)
     pico_enable_stdio_usb(picogus 0)
     pico_enable_stdio_semihosting(picogus 0)
 endif()

sw/adlibplay.cpp

@@ -18,7 +18,12 @@
 
 #include "pico/audio_i2s.h"
 
+#ifdef OPL_NUKED
+#include "Nuked-OPL3/opl3.h"
+extern opl3_chip nuked_chip;
+#else
 #include "opl.h"
+#endif
 
 #if PICO_ON_DEVICE
 #include "pico/binary_info.h"
@@ -70,9 +75,26 @@ void play_adlib() {
     uint32_t start, end;
 
     struct audio_buffer_pool *ap = init_audio();
+
+    OPL3_Reset(&nuked_chip, 49716);
+
     for (;;) {
         struct audio_buffer *buffer = take_audio_buffer(ap, true);
+#ifdef OPL_NUKED
+        int16_t *samples = (int16_t *) buffer->buffer->bytes;
+        uint32_t audio_begin = time_us_32();
+        // putchar('=');
+        for (int i = 0; i < buffer->max_sample_count; ++i) {
+            OPL3_Generate(&nuked_chip, samples + (i << 1));
+        }
+        uint32_t audio_elapsed = time_us_32() - audio_begin;
+        if (audio_elapsed > 1280) {
+            printf("took too long: %u\n", audio_elapsed);
+        }
+        buffer->sample_count = buffer->max_sample_count;
+#else
         OPL_Pico_Mix_callback(buffer);
+#endif
         // putchar((unsigned char)buffer->buffer->bytes[1]);
         give_audio_buffer(ap, buffer);
     }

sw/picogus.cpp

@@ -27,14 +27,20 @@ psram_spi_inst_t* async_spi_inst;
 #define BAUD_RATE   115200
 
 #ifdef SOUND_OPL
+#ifdef OPL_NUKED
+#include "Nuked-OPL3/opl3.h"
+uint8_t opl_reg;
+opl3_chip nuked_chip = {};
+#else
 #include "opl.h"
-static uint16_t basePort = 0x388u;
-
-void play_adlib(void);
 extern "C" int OPL_Pico_Init(unsigned int);
 extern "C" void OPL_Pico_PortWrite(opl_port_t, unsigned int);
 extern "C" unsigned int OPL_Pico_PortRead(opl_port_t);
 #endif
+static uint16_t basePort = 0x388u;
+
+void play_adlib(void);
+#endif
 
 #ifdef SOUND_GUS
 #include "gus-x.cpp"
@@ -265,13 +271,21 @@ __force_inline void handle_iow(void) {
     case 0:
         // Fast write
         pio_sm_put(pio0, iow_sm, IO_END);
+#ifdef OPL_NUKED
+        opl_reg = iow_read & 0xFF;
+#else
         OPL_Pico_PortWrite(OPL_REGISTER_PORT, iow_read & 0xFF);
+#endif
         // Fast write - return early as we've already written 0x0u to the PIO
         return;
         break;
     case 1:
         pio_sm_put(pio0, iow_sm, IO_WAIT);
+#ifdef OPL_NUKED
+        OPL3_WriteRegBuffered(&nuked_chip, opl_reg, iow_read & 0xFF);
+#else
         OPL_Pico_PortWrite(OPL_DATA_PORT, iow_read & 0xFF);
+#endif
         // __dsb();
         break;
     }
@@ -364,6 +378,7 @@ __force_inline void handle_ior(void) {
         // gpio_xor_mask(LED_PIN);
     } else // if follows down below
 #elif defined(SOUND_OPL)
+#if 0  // commenting out because hand386
     if (port == basePort) {
         // Tell PIO to wait for data
         pio_sm_put(pio0, ior_sm, IO_WAIT);
@@ -371,6 +386,7 @@ __force_inline void handle_ior(void) {
         // OR with 0x0000ff00 is required to set pindirs in the PIO
         pio_sm_put(pio0, ior_sm, IOR_SET_VALUE | value);
     } else // if follows down below
+#endif
 #elif defined(SOUND_MPU)
     if (port == basePort) {
         // Tell PIO to wait for data
@@ -510,7 +526,9 @@ int main()
 
 #ifdef SOUND_OPL
     puts("Creating OPL");
+#ifndef OPL_NUKED
     OPL_Pico_Init(basePort);
+#endif
     multicore_launch_core1(&play_adlib);
 #endif // SOUND_OPL