From 35f20a16b8bb85677f3ff52e2c5d99bddb4899a6 Mon Sep 17 00:00:00 2001
From: iris <iris.kaizen@pm.me>
Date: Wed, 20 May 2026 17:55:07 +0200
Subject: [PATCH] i should implement DSP DMA...

---
 CMakeLists.txt                 |   3 +-
 core/broadway.cpp              |  40 ++++++++++-
 core/broadway.hpp              |  13 +++-
 core/broadway/instructions.cpp | 124 ++++++++++++++++++++++++++++++--
 core/broadway/mmio/ai.cpp      |  10 +--
 core/broadway/mmio/ai.hpp      |   4 +-
 core/broadway/mmio/dsp.cpp     | 125 ++++++++++++++++++++++++++++++++-
 core/broadway/mmio/dsp.hpp     |  17 ++++-
 core/broadway/mmio/si.cpp      |  46 ++++++++++++
 core/broadway/mmio/si.hpp      |  75 ++++++++++++++++++++
 core/broadway/mmio/vi.cpp      |  55 +++++++++++++++
 core/broadway/mmio/vi.hpp      |   5 +-
 core/mem.cpp                   |   2 +-
 core/mem.hpp                   |   4 +-
 main.cpp                       |   2 +-
 15 files changed, 500 insertions(+), 25 deletions(-)
 create mode 100644 core/broadway/mmio/si.cpp
 create mode 100644 core/broadway/mmio/si.hpp

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 08424c1..9899385 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -33,6 +33,7 @@ add_executable(weee main.cpp core/mem.cpp core/loaders/elf.cpp
     core/broadway/mmio/mi.cpp
     core/broadway/mmio/dsp.cpp
     core/broadway/mmio/ai.cpp
-    core/broadway/mmio/exi.cpp)
+    core/broadway/mmio/exi.cpp
+    core/broadway/mmio/si.cpp)
 target_link_libraries(weee PUBLIC SDL3::SDL3 capstone)
 target_include_directories(weee PUBLIC core)
\ No newline at end of file
diff --git a/core/broadway.cpp b/core/broadway.cpp
index be628b3..316f5b0 100644
--- a/core/broadway.cpp
+++ b/core/broadway.cpp
@@ -16,9 +16,10 @@ broadway::broadway() {
 void broadway::set_pc(ircolib::u32 value) { pc = value; }
 
 void broadway::run(mem &mem) {
-    for (int i = 0; i < 12150000; i++) {
-        // std::println("pc: 0x{:08X}", pc);
-        execute(fetch(mem), mem);
+    std::println("pc: 0x{:08X}", pc);
+    for (int i = 0; i < 1000000; i++) {
+        ircolib::u32 instr = fetch(mem);
+        execute(instr, mem);
     }
 }
 
@@ -58,6 +59,12 @@ void broadway::decode_special2(ircolib::u32 instr, mem &mem) {
     case 0x000:
         cmp(instr);
         break;
+    case 0x008:
+        subfc(instr);
+        break;
+    case 0x00A:
+        addc(instr);
+        break;
     case 0x013:
         mfcr(instr);
         break;
@@ -76,6 +83,12 @@ void broadway::decode_special2(ircolib::u32 instr, mem &mem) {
     case 0x053:
         mfmsr(instr);
         break;
+    case 0x088:
+        subfe(instr);
+        break;
+    case 0x08A:
+        adde(instr);
+        break;
     case 0x090:
         mtcrf(instr);
         break;
@@ -85,12 +98,21 @@ void broadway::decode_special2(ircolib::u32 instr, mem &mem) {
     case 0x097:
         stwx(instr, mem);
         break;
+    case 0x0CA:
+        addze(instr);
+        break;
     case 0x0D2:
         ircolib::warn("broadway TODO mtsr (pc 0x{:08X})", pc - 4);
         break;
     case 0x0EB:
         mullw(instr);
         break;
+    case 0x117:
+        lhzx(instr, mem);
+        break;
+    case 0x173:
+        mftb(instr);
+        break;
     case 0x1BC:
         or (instr);
         break;
@@ -109,6 +131,9 @@ void broadway::decode_special2(ircolib::u32 instr, mem &mem) {
         break;
     case 0x256: // sync
         break;
+    case 0x318:
+        sraw(instr);
+        break;
     default:
         std::println("broadway unknown special2 {} (0x{:04X}) (pc 0x{:08X})", secondary, secondary, pc - 4);
         std::println("disassembly:");
@@ -142,6 +167,9 @@ void broadway::execute(ircolib::u32 instr, mem &mem) {
     case 7:
         mulli(instr);
         break;
+    case 8:
+        subfic(instr);
+        break;
     case 10:
         cmpli(instr);
         break;
@@ -181,6 +209,9 @@ void broadway::execute(ircolib::u32 instr, mem &mem) {
     case 25:
         oris(instr);
         break;
+    case 26:
+        xori(instr);
+        break;
     case 28:
         andi(instr);
         break;
@@ -217,6 +248,9 @@ void broadway::execute(ircolib::u32 instr, mem &mem) {
     case 44:
         sth(instr, mem);
         break;
+    case 45:
+        sthu(instr, mem);
+        break;
     case 50:
         lfd(instr, mem);
         break;
diff --git a/core/broadway.hpp b/core/broadway.hpp
index 00ad1cf..01141d8 100644
--- a/core/broadway.hpp
+++ b/core/broadway.hpp
@@ -17,7 +17,7 @@ struct broadway {
     void execute(ircolib::u32, mem &);
 
     bool disasm_available = true;
-    ircolib::u32 pc = 0, lr = 0, ctr = 0, cr = 0, srr0 = 0, fpscr = 0, msr = 0;
+    ircolib::u32 pc = 0, lr = 0, ctr = 0, cr = 0, srr0 = 0, fpscr = 0, msr = 0, tbl = 0, tbu = 0;
     union {
         struct {
             unsigned bytecount : 7;
@@ -66,6 +66,9 @@ struct broadway {
     void andis(ircolib::u32);
     void and(ircolib::u32);
     void add(ircolib::u32);
+    void addc(ircolib::u32);
+    void adde(ircolib::u32);
+    void addze(ircolib::u32);
     void addis(ircolib::u32);
     void addi(ircolib::u32);
     void addic(ircolib::u32);
@@ -79,6 +82,7 @@ struct broadway {
     void stw(ircolib::u32, mem &);
     void stb(ircolib::u32, mem &);
     void stwu(ircolib::u32, mem &);
+    void sthu(ircolib::u32, mem &);
     void stwx(ircolib::u32, mem &);
     void stbu(ircolib::u32, mem &);
     void sth(ircolib::u32, mem &);
@@ -86,6 +90,7 @@ struct broadway {
     void lwz(ircolib::u32, mem &);
     void lwzx(ircolib::u32, mem &);
     void lhz(ircolib::u32, mem &);
+    void lhzx(ircolib::u32, mem &);
     void lfd(ircolib::u32, mem &);
     void bclrx(ircolib::u32);
     void cmpi(ircolib::u32);
@@ -106,8 +111,14 @@ struct broadway {
     void mulli(ircolib::u32);
     void nand(ircolib::u32);
     void subf(ircolib::u32);
+    void subfc(ircolib::u32);
+    void subfic(ircolib::u32);
+    void subfe(ircolib::u32);
     void or (ircolib::u32);
+    void xori(ircolib::u32);
     void divwu(ircolib::u32);
+    void mftb(ircolib::u32);
+    void sraw(ircolib::u32);
 
     inline void cr0_update(bool condition, ircolib::s32 result) {
         if (condition) {
diff --git a/core/broadway/instructions.cpp b/core/broadway/instructions.cpp
index c1e42bd..4d75c12 100644
--- a/core/broadway/instructions.cpp
+++ b/core/broadway/instructions.cpp
@@ -8,6 +8,31 @@ void broadway::add(ircolib::u32 instr) {
     cr0_update(instr & 1, gpr[utils::RD(instr)]);
 }
 
+void broadway::addc(ircolib::u32 instr) {
+    ircolib::u32 sum;
+    bool carry = __builtin_add_overflow(gpr[utils::RA(instr)], gpr[utils::RB(instr)], &sum);
+    cr0_update(instr & 1, sum);
+    xer.ca = carry;
+    gpr[utils::RD(instr)] = sum;
+}
+
+void broadway::adde(ircolib::u32 instr) {
+    ircolib::u32 sum;
+    bool c0 = __builtin_add_overflow(gpr[utils::RA(instr)], gpr[utils::RB(instr)], &sum);
+    bool c1 = __builtin_add_overflow(sum, xer.ca, &sum);
+    cr0_update(instr & 1, sum);
+    xer.ca = c0 | c1;
+    gpr[utils::RD(instr)] = sum;
+}
+
+void broadway::addze(ircolib::u32 instr) {
+    ircolib::u32 sum;
+    bool c1 = __builtin_add_overflow(gpr[utils::RA(instr)], xer.ca, &sum);
+    cr0_update(instr & 1, sum);
+    xer.ca = c1;
+    gpr[utils::RD(instr)] = sum;
+}
+
 void broadway::addi(ircolib::u32 instr) {
     if (utils::RA(instr) == 0) { // li
         gpr[utils::RD(instr)] = ircolib::s32(utils::SIMM(instr));
@@ -17,13 +42,19 @@ void broadway::addi(ircolib::u32 instr) {
     gpr[utils::RD(instr)] = gpr[utils::RA(instr)] + (ircolib::s32(utils::SIMM(instr)));
 }
 
-void broadway::addicr(ircolib::u32 instr) {
-    gpr[utils::RD(instr)] = gpr[utils::RA(instr)] + (ircolib::s32(utils::SIMM(instr)));
-    cr0_update(true, gpr[utils::RD(instr)]);
+void broadway::addic(ircolib::u32 instr) {
+    ircolib::u32 sum;
+    bool carry = __builtin_add_overflow(gpr[utils::RA(instr)], ircolib::s32(utils::SIMM(instr)), &sum);
+    gpr[utils::RD(instr)] = sum;
+    xer.ca = carry;
 }
 
-void broadway::addic(ircolib::u32 instr) {
-    gpr[utils::RD(instr)] = gpr[utils::RA(instr)] + (ircolib::s32(utils::SIMM(instr)));
+void broadway::addicr(ircolib::u32 instr) {
+    ircolib::u32 sum;
+    bool carry = __builtin_add_overflow(gpr[utils::RA(instr)], ircolib::s32(utils::SIMM(instr)), &sum);
+    cr0_update(true, sum);
+    gpr[utils::RD(instr)] = sum;
+    xer.ca = carry;
 }
 
 void broadway::addis(ircolib::u32 instr) {
@@ -167,6 +198,22 @@ void broadway::stwu(ircolib::u32 instr, mem &mem) {
              });
 }
 
+void broadway::sthu(ircolib::u32 instr, mem &mem) {
+    if (utils::RA(instr) == 0)
+        ircolib::panic("broadway::sthu with ra == 0");
+
+    const ircolib::u32 EA = ircolib::s32(gpr[utils::RA(instr)]) + utils::SIMM(instr);
+    auto _ = mem.write16(EA, gpr[utils::RS(instr)])
+             .and_then([&] {
+                 gpr[utils::RA(instr)] = EA;
+                 return std::expected<void, std::string>();
+             })
+             .or_else([&](std::string e) {
+                 ircolib::panic("sthu broadway write failed. Reason: {} (pc: 0x{:08X})", e, pc - 4);
+                 return std::expected<void, std::string>();
+             });
+}
+
 void broadway::stbu(ircolib::u32 instr, mem &mem) {
     if (utils::RA(instr) == 0)
         ircolib::panic("broadway::stbu with ra == 0");
@@ -288,6 +335,22 @@ void broadway::lhz(ircolib::u32 instr, mem &mem) {
                             .value();
 }
 
+void broadway::lhzx(ircolib::u32 instr, mem &mem) {
+    ircolib::u32 b = gpr[utils::RA(instr)];
+    if (utils::RA(instr) == 0)
+        b = 0;
+
+    ircolib::u32 ea = ircolib::s32(b) + gpr[utils::RB(instr)];
+
+    gpr[utils::RD(instr)] = mem.read16(ea)
+                            .and_then([&](ircolib::u32 val) { return std::expected<ircolib::u32, std::string>(val); })
+                            .or_else([&](std::string e) {
+                                ircolib::panic("lhzx broadway read failed. Reason {} (pc: 0x{:08X})", e, pc - 4);
+                                return std::expected<ircolib::u32, std::string>();
+                            })
+                            .value();
+}
+
 void broadway::lbz(ircolib::u32 instr, mem &mem) {
     ircolib::u32 b = gpr[utils::RA(instr)];
     if (utils::RA(instr) == 0)
@@ -505,11 +568,39 @@ void broadway::subf(ircolib::u32 instr) {
     cr0_update(instr & 1, gpr[utils::RD(instr)]);
 }
 
+void broadway::subfc(ircolib::u32 instr) {
+    ircolib::u32 sum;
+    bool c0 = __builtin_add_overflow(~gpr[utils::RA(instr)], 1, &sum);
+    bool c1 = __builtin_add_overflow(sum, gpr[utils::RB(instr)], &sum);
+    cr0_update(instr & 1, sum);
+    xer.ca = !c0 | c1;
+    gpr[utils::RD(instr)] = sum;
+}
+
+void broadway::subfic(ircolib::u32 instr) {
+    ircolib::u32 sum;
+    bool c0 = __builtin_add_overflow(~gpr[utils::RA(instr)], 1, &sum);
+    bool c1 = __builtin_add_overflow(sum, utils::SIMM(instr), &sum);
+    xer.ca = !c0 | c1;
+    gpr[utils::RD(instr)] = sum;
+}
+
+void broadway::subfe(ircolib::u32 instr) {
+    ircolib::u32 sum;
+    bool c0 = __builtin_add_overflow(~gpr[utils::RA(instr)], gpr[utils::RB(instr)], &sum);
+    bool c1 = __builtin_add_overflow(sum, xer.ca, &sum);
+    cr0_update(instr & 1, sum);
+    xer.ca = c0 | c1;
+    gpr[utils::RD(instr)] = sum;
+}
+
 void broadway:: or (ircolib::u32 instr) {
     gpr[utils::RA(instr)] = gpr[utils::RS(instr)] | gpr[utils::RB(instr)];
     cr0_update(instr & 1, gpr[utils::RA(instr)]);
 }
 
+void broadway::xori(ircolib::u32 instr) { gpr[utils::RA(instr)] = gpr[utils::RS(instr)] ^ utils::UIMM(instr); }
+
 void broadway::mullw(ircolib::u32 instr) {
     gpr[utils::RD(instr)] = ircolib::u64(gpr[utils::RA(instr)]) * ircolib::u64(gpr[utils::RB(instr)]);
 }
@@ -543,4 +634,27 @@ void broadway::divwu(ircolib::u32 instr) {
     gpr[utils::RD(instr)] = dividend / divisor;
     cr0_update(instr & 1, gpr[utils::RD(instr)]);
 }
+
+void broadway::mftb(ircolib::u32 instr) {
+    const ircolib::u32 tbr = (instr >> 11) & 0x3FF;
+
+    if (tbr != 392 && tbr != 424)
+        ircolib::panic("broadway::mftb with tbr != 268 && != 269 ({})", tbr);
+
+    if (tbr == 392)
+        gpr[utils::RD(instr)] = tbl;
+
+    if (tbr == 424)
+        gpr[utils::RD(instr)] = tbu;
+}
+
+void broadway::sraw(ircolib::u32 instr) {
+    ircolib::u8 shift = std::min(gpr[utils::RB(instr)] & 0x3f, ircolib::u32(31));
+    ircolib::s32 rs = gpr[utils::RS(instr)];
+    ircolib::s32 result = rs >> shift;
+    ircolib::u32 mask = (1 << shift) - 1;
+    cr0_update(instr & 1, result);
+    xer.ca = (rs < 0) & ((ircolib::u32(rs) & mask) != 0);
+    gpr[utils::RA(instr)] = result;
+}
 } // namespace weee::core
diff --git a/core/broadway/mmio/ai.cpp b/core/broadway/mmio/ai.cpp
index 5e6d119..98617c3 100644
--- a/core/broadway/mmio/ai.cpp
+++ b/core/broadway/mmio/ai.cpp
@@ -3,29 +3,29 @@
 #include <ircolib/log.hpp>
 
 namespace weee::core {
-ai::ai(mem &mem) {
+audio_interface::audio_interface(mem &mem) {
     mem.register_read32_handler(0x0c006c00, 0x0c006c1f, [&](ircolib::u32 addr) { return read32(addr); });
     mem.register_write32_handler(0x0c006c00, 0x0c006c1f,
                                  [&](ircolib::u32 addr, ircolib::u32 value) { return write32(addr, value); });
 }
 
-ircolib::u32 ai::read32(ircolib::u32 addr) {
+ircolib::u32 audio_interface::read32(ircolib::u32 addr) {
     switch (addr) {
     case 0:
         return ctrl.raw;
     default:
-        ircolib::panic("ai::read32 from unimplemented addr 0x{:08X}", addr);
+        ircolib::panic("audio_interface::read32 from unimplemented addr 0x{:08X}", addr);
         return 0;
     }
 }
 
-void ai::write32(ircolib::u32 addr, ircolib::u32 value) {
+void audio_interface::write32(ircolib::u32 addr, ircolib::u32 value) {
     switch (addr) {
     case 0:
         ctrl.raw = value;
         break;
     default:
-        ircolib::panic("ai::write32 to unimplemented addr 0x{:08X} with value 0x{:08X}", addr, value);
+        ircolib::panic("audio_interface::write32 to unimplemented addr 0x{:08X} with value 0x{:08X}", addr, value);
     }
 }
 } // namespace weee::core
diff --git a/core/broadway/mmio/ai.hpp b/core/broadway/mmio/ai.hpp
index d4ead02..a4cec32 100644
--- a/core/broadway/mmio/ai.hpp
+++ b/core/broadway/mmio/ai.hpp
@@ -3,8 +3,8 @@
 
 namespace weee::core {
 struct mem;
-struct ai {
-    ai(mem &);
+struct audio_interface {
+    audio_interface(mem &);
 
     ircolib::u32 read32(ircolib::u32);
     void write32(ircolib::u32, ircolib::u32);
diff --git a/core/broadway/mmio/dsp.cpp b/core/broadway/mmio/dsp.cpp
index 381e673..e858362 100644
--- a/core/broadway/mmio/dsp.cpp
+++ b/core/broadway/mmio/dsp.cpp
@@ -7,12 +7,77 @@ dsp::dsp(mem &mem) {
     mem.register_read16_handler(0x0c005000, 0x0c0051ff, [&](ircolib::u32 addr) { return read16(addr); });
     mem.register_write16_handler(0x0c005000, 0x0c0051ff,
                                  [&](ircolib::u32 addr, ircolib::u16 value) { return write16(addr, value); });
+
+    mem.register_read32_handler(0x0c005000, 0x0c0051ff, [&](ircolib::u32 addr) { return read32(addr); });
+    mem.register_write32_handler(0x0c005000, 0x0c0051ff,
+                                 [&](ircolib::u32 addr, ircolib::u32 value) { return write32(addr, value); });
+}
+
+ircolib::u32 dsp::read32(ircolib::u32 addr) {
+    switch (addr) {
+    case 0x20:
+        return ar_dma_mmaddr.whole;
+    case 0x24:
+        return ar_dma_araddr.whole;
+    case 0x28:
+        return ar_dma_cnt.whole;
+    case 0x30:
+        return dma_start_addr.whole;
+    default:
+        ircolib::panic("dsp::read32 from unimplemented addr 0x{:08X}", addr);
+        return 0;
+    }
+}
+
+void dsp::write32(ircolib::u32 addr, ircolib::u32 value) {
+    switch (addr) {
+    case 0x20:
+        ar_dma_mmaddr.whole = value;
+        break;
+    case 0x24:
+        ar_dma_araddr.whole = value;
+        break;
+    case 0x28:
+        ar_dma_cnt.whole = value;
+        break;
+    case 0x30:
+        dma_start_addr.whole = value;
+        break;
+    default:
+        ircolib::panic("dsp::write32 to unimplemented addr 0x{:08X} with value 0x{:08X}", addr, value);
+    }
 }
 
 ircolib::u16 dsp::read16(ircolib::u32 addr) {
     switch (addr) {
+    case 0x00:
+        return dsp_mail_hi;
+    case 0x02:
+        return dsp_mail_lo;
+    case 0x04:
+        return cpu_mail_hi;
+    case 0x06:
+        return cpu_mail_lo;
     case 0x0a:
         return csr.raw;
+    case 0x12:
+        return ar_size;
+    case 0x20:
+        return ar_dma_mmaddr.hi;
+    case 0x22:
+        return ar_dma_mmaddr.lo;
+    case 0x24:
+        return ar_dma_araddr.hi;
+    case 0x26:
+        return ar_dma_araddr.lo;
+    case 0x28:
+        return ar_dma_cnt.hi;
+    case 0x2a:
+        return ar_dma_cnt.lo;
+    case 0x30:
+        return dma_start_addr.hi;
+    case 0x32:
+        return dma_start_addr.lo;
     default:
         ircolib::panic("dsp::read16 from unimplemented addr 0x{:08X}", addr);
         return 0;
@@ -21,11 +86,67 @@ ircolib::u16 dsp::read16(ircolib::u32 addr) {
 
 void dsp::write16(ircolib::u32 addr, ircolib::u16 value) {
     switch (addr) {
+    case 0x00:
+        dsp_mail_hi = value;
+        break;
+    case 0x02:
+        dsp_mail_lo = value;
+        break;
     case 0x0a:
-        csr.raw = value;
+        {
+            Csr ccsr = {.raw = value};
+            Csr ocsr = csr;
+            csr = ccsr;
+            if (csr.res || (ocsr.boot_mode != ccsr.boot_mode && ccsr.boot_mode)) {
+                cpu_mail_hi = 0;
+                cpu_mail_lo = 0;
+                dsp_mail_hi = 0;
+                dsp_mail_lo = 0;
+            }
+
+            if (csr.piint)
+                csr.piint = false;
+
+            if (csr.aidint)
+                csr.aidint = false;
+
+            if (csr.arint)
+                csr.arint = false;
+
+            if (csr.dspint)
+                csr.dspint = false;
+        }
+        break;
+    case 0x12:
+        ar_size = value;
+        break;
+    case 0x20:
+        ar_dma_mmaddr.hi = value;
+        break;
+    case 0x22:
+        ar_dma_mmaddr.lo = value;
+        break;
+    case 0x24:
+        ar_dma_araddr.hi = value;
+        break;
+    case 0x26:
+        ar_dma_araddr.lo = value;
+        break;
+    case 0x28:
+        ar_dma_cnt.hi = value;
+        break;
+    case 0x2a:
+        ar_dma_cnt.lo = value;
+        csr.arint = true;
+        break;
+    case 0x30:
+        dma_start_addr.hi = value;
+        break;
+    case 0x32:
+        dma_start_addr.lo = value;
         break;
     default:
-        ircolib::panic("dsp::read16 from unimplemented addr 0x{:08X}", addr);
+        ircolib::panic("dsp::write16 from unimplemented addr 0x{:08X} with value 0x{:04X}", addr, value);
     }
 }
 } // namespace weee::core
diff --git a/core/broadway/mmio/dsp.hpp b/core/broadway/mmio/dsp.hpp
index d18f4a7..34f632d 100644
--- a/core/broadway/mmio/dsp.hpp
+++ b/core/broadway/mmio/dsp.hpp
@@ -7,8 +7,10 @@ struct dsp {
     dsp(mem &);
     ircolib::u16 read16(ircolib::u32);
     void write16(ircolib::u32, ircolib::u16);
+    ircolib::u32 read32(ircolib::u32);
+    void write32(ircolib::u32, ircolib::u32);
 
-    union {
+    union Csr {
         struct {
             unsigned res : 1;
             unsigned piint : 1;
@@ -21,10 +23,21 @@ struct dsp {
             unsigned dspint_mask : 1;
             unsigned int_status : 1;
             unsigned : 1;
-            unsigned res2 : 1;
+            unsigned boot_mode : 1;
             unsigned : 4;
         };
         ircolib::u16 raw;
     } csr;
+
+    union {
+        struct {
+            ircolib::u32 lo;
+            ircolib::u32 hi;
+        };
+        ircolib::u64 whole;
+    } ar_dma_mmaddr, ar_dma_araddr, ar_dma_cnt, dma_start_addr;
+
+    ircolib::u16 ar_size;
+    ircolib::u16 dsp_mail_hi = 0, dsp_mail_lo = 0, cpu_mail_hi = 0, cpu_mail_lo = 0;
 };
 } // namespace weee::core
diff --git a/core/broadway/mmio/si.cpp b/core/broadway/mmio/si.cpp
new file mode 100644
index 0000000..2d4c952
--- /dev/null
+++ b/core/broadway/mmio/si.cpp
@@ -0,0 +1,46 @@
+#include <broadway/mmio/si.hpp>
+#include <mem.hpp>
+#include <ircolib/log.hpp>
+
+namespace weee::core {
+serial_interface::serial_interface(mem &mem) {
+    mem.register_read32_handler(0x0c006400, 0x0c0064ff, [&](ircolib::u32 addr) { return read32(addr); });
+    mem.register_write32_handler(0x0c006400, 0x0c0064ff,
+                                 [&](ircolib::u32 addr, ircolib::u32 value) { return write32(addr, value); });
+}
+
+ircolib::u32 serial_interface::read32(ircolib::u32 addr) {
+    switch (addr) {
+    case 0x30:
+        return sipoll.raw;
+    case 0x34:
+        return sicomcsr.raw;
+    case 0x38:
+        return sisr.raw;
+    case 0x3C:
+        return clock_lk.raw;
+    default:
+        ircolib::panic("serial_interface::read32 from unimplemented addr 0x{:08X}", addr);
+        return 0;
+    }
+}
+
+void serial_interface::write32(ircolib::u32 addr, ircolib::u32 value) {
+    switch (addr) {
+    case 0x30:
+        sipoll.raw = value;
+        break;
+    case 0x34:
+        sicomcsr.raw = value;
+        break;
+    case 0x38:
+        sisr.raw = value;
+        break;
+    case 0x3C:
+        clock_lk.raw = value;
+        break;
+    default:
+        ircolib::panic("serial_interface::write32 to unimplemented addr 0x{:08X} with value 0x{:08X}", addr, value);
+    }
+}
+} // namespace weee::core
diff --git a/core/broadway/mmio/si.hpp b/core/broadway/mmio/si.hpp
new file mode 100644
index 0000000..64125c8
--- /dev/null
+++ b/core/broadway/mmio/si.hpp
@@ -0,0 +1,75 @@
+#pragma once
+#include <ircolib/types.hpp>
+
+namespace weee::core {
+struct mem;
+struct serial_interface {
+    serial_interface(mem &);
+
+    ircolib::u32 read32(ircolib::u32);
+    void write32(ircolib::u32, ircolib::u32);
+
+    union {
+        struct {
+            unsigned vbcpy : 4;
+            unsigned en : 4;
+            unsigned y : 8;
+            unsigned x : 8;
+            unsigned : 8;
+        };
+
+        ircolib::u32 raw;
+    } sipoll;
+
+    union {
+        struct {
+            unsigned tstart : 1;
+            unsigned channel : 2;
+            unsigned cben : 1;
+            unsigned cmden : 1;
+            unsigned inlength : 7;
+            unsigned : 1;
+            unsigned outlength : 7;
+            unsigned : 1;
+            unsigned chen : 1;
+            unsigned chnum : 2;
+            unsigned rdstintmsk : 1;
+            unsigned rdstint : 1;
+            unsigned comerr : 1;
+            unsigned tcintmsk : 1;
+            unsigned tcint : 1;
+        };
+        ircolib::u32 raw;
+    } sicomcsr;
+
+    union {
+        struct {
+            unsigned : 31;
+            unsigned lock : 1;
+        };
+
+        ircolib::u32 raw;
+    } clock_lk;
+
+    union {
+        struct {
+            unsigned joy3 : 6;
+            unsigned : 2;
+            unsigned joy2 : 6;
+            unsigned : 2;
+            unsigned joy1 : 6;
+            unsigned : 2;
+            unsigned unrun : 1;
+            unsigned ovrun0 : 1;
+            unsigned coll0 : 1;
+            unsigned norep0 : 1;
+            unsigned wrst0 : 1;
+            unsigned rdst0 : 1;
+            unsigned : 1;
+            unsigned wr : 1;
+        };
+
+        ircolib::u32 raw;
+    } sisr;
+};
+} // namespace weee::core
diff --git a/core/broadway/mmio/vi.cpp b/core/broadway/mmio/vi.cpp
index f8b70fc..736c49a 100644
--- a/core/broadway/mmio/vi.cpp
+++ b/core/broadway/mmio/vi.cpp
@@ -4,12 +4,67 @@
 
 namespace weee::core {
 video_interface::video_interface(mem &mem) {
+    mem.register_read16_handler(0x0c002000, 0x0c0020ff, [&](ircolib::u32 addr) { return read16(addr); });
+    mem.register_read32_handler(0x0c002000, 0x0c0020ff, [&](ircolib::u32 addr) { return read32(addr); });
     mem.register_write16_handler(0x0c002000, 0x0c0020ff,
                                  [&](ircolib::u32 addr, ircolib::u16 value) { write16(addr, value); });
     mem.register_write32_handler(0x0c002000, 0x0c0020ff,
                                  [&](ircolib::u32 addr, ircolib::u32 value) { write32(addr, value); });
 }
 
+ircolib::u16 video_interface::read16(ircolib::u32 addr) {
+    switch (addr) {
+    case 0x00:
+        return vtr.raw;
+    case 0x02:
+        return dcr.raw;
+    case 0x4a:
+        return hsr.raw;
+    case 0x6c:
+        return viclk & 1;
+    case 0x70:
+        return 0x0280;
+    default:
+        ircolib::panic("video_interface::read16 from unimplemented addr 0x{:04X}", addr);
+        return 0;
+    }
+}
+
+ircolib::u32 video_interface::read32(ircolib::u32 addr) {
+    switch (addr) {
+    case 0x02:
+        return dcr.raw;
+    case 0x04:
+        return htr0.raw;
+    case 0x08:
+        return htr1.raw;
+    case 0x0c:
+        return vto.raw;
+    case 0x10:
+        return vte.raw;
+    case 0x14:
+        return bbei.raw;
+    case 0x18:
+        return bboi.raw;
+    case 0x1c:
+        return tfbl.raw & 0x1ffffe00;
+    case 0x24:
+        return bfbl.raw & 0x10fffe00;
+    case 0x4c:
+    case 0x50:
+    case 0x54:
+        return fct0[addr - 0x4c].raw;
+    case 0x58:
+    case 0x5c:
+    case 0x60:
+    case 0x64:
+        return fct1[addr - 0x58].raw;
+    default:
+        ircolib::panic("video_interface::read32 from unimplemented addr 0x{:04X}", addr);
+        return 0;
+    }
+}
+
 void video_interface::write16(ircolib::u32 addr, ircolib::u16 value) {
     switch (addr) {
     case 0x00:
diff --git a/core/broadway/mmio/vi.hpp b/core/broadway/mmio/vi.hpp
index 080b0eb..77388b3 100644
--- a/core/broadway/mmio/vi.hpp
+++ b/core/broadway/mmio/vi.hpp
@@ -8,6 +8,9 @@ struct video_interface {
     video_interface(mem &);
     void write16(ircolib::u32, ircolib::u16);
     void write32(ircolib::u32, ircolib::u32);
+    ircolib::u16 read16(ircolib::u32);
+    ircolib::u32 read32(ircolib::u32);
+
     ircolib::u32 xfb_top_addr() {
         auto addr = tfbl.fbb;
         if (tfbl.page) {
@@ -96,7 +99,7 @@ struct video_interface {
             unsigned fbb : 24;
         };
         ircolib::u32 raw;
-    } tfbl, bfbl;
+    } tfbl{}, bfbl{};
 
     union FCT012 {
         struct {
diff --git a/core/mem.cpp b/core/mem.cpp
index f0c8afa..bb608f3 100644
--- a/core/mem.cpp
+++ b/core/mem.cpp
@@ -4,7 +4,7 @@
 #include <ircolib/mem_access.hpp>
 
 namespace weee::core {
-mem::mem() : vi(*this), pi(*this), mi(*this), dsp(*this), ai(*this), exi(*this) {
+mem::mem() : vi(*this), pi(*this), mi(*this), dsp(*this), ai(*this), exi(*this), si(*this) {
     mem1.resize(24_mib);
     std::fill(mem1.begin(), mem1.end(), 0);
     ipl.resize(1_mib);
diff --git a/core/mem.hpp b/core/mem.hpp
index 0b7a742..35a2449 100644
--- a/core/mem.hpp
+++ b/core/mem.hpp
@@ -8,6 +8,7 @@
 #include <broadway/mmio/dsp.hpp>
 #include <broadway/mmio/ai.hpp>
 #include <broadway/mmio/exi.hpp>
+#include <broadway/mmio/si.hpp>
 #include <functional>
 #include <expected>
 
@@ -92,6 +93,7 @@ struct mem {
     memory_interface mi;
     dsp dsp;
     exi exi;
-    ai ai;
+    audio_interface ai;
+    serial_interface si;
 };
 } // namespace weee::core
diff --git a/main.cpp b/main.cpp
index d6a1afb..84ad9ad 100644
--- a/main.cpp
+++ b/main.cpp
@@ -67,7 +67,7 @@ int main(int argc, char **argv) {
                 open = false;
         }
 
-        SDL_ConvertPixels(640, 240, SDL_PIXELFORMAT_UYVY, &mem.mem1[vi.xfb_top_addr()], 640 * 4, SDL_PIXELFORMAT_BGR24,
+        SDL_ConvertPixels(640, 240, SDL_PIXELFORMAT_UYVY, &mem.mem1[0], 640 * 4, SDL_PIXELFORMAT_BGR24,
                           rgbTexture.data(), 640 * 3);
 
         SDL_RenderClear(renderer);