wifi improvements:

* implement channels
* rework power-down support, fixing bugs
* fix bug when W_BeaconInterval is zero
* fix potential missing IRQs when writing to W_IE

6 files changed, 339 insertions, 129 deletions

diff --git a/src/NDS.cpp b/src/NDS.cpp
index 284f6eb..68227ea 100644
--- a/src/NDS.cpp
+++ b/src/NDS.cpp
@@ -1845,7 +1845,7 @@ void NDS::debug(u32 param)
     //for (int i = 0; i < 9; i++)
     //    printf("VRAM %c: %02X\n", 'A'+i, GPU->VRAMCNT[i]);
 
-    Platform::FileHandle* shit = Platform::OpenFile("debug/DSfirmware.bin", FileMode::Write);
+    Platform::FileHandle* shit = Platform::OpenFile("debug/pokeplat.bin", FileMode::Write);
     Platform::FileWrite(ARM9.ITCM, 0x8000, 1, shit);
     for (u32 i = 0x02000000; i < 0x02400000; i+=4)
     {
diff --git a/src/Wifi.cpp b/src/Wifi.cpp
index 4da253e..12926c6 100644
--- a/src/Wifi.cpp
+++ b/src/Wifi.cpp
@@ -159,11 +159,45 @@ void Wifi::Reset()
     #undef BBREG_FIXED
 
     const Firmware& fw = NDS.SPI.GetFirmware();
+    const auto& fwheader = fw.GetHeader();
 
-    RFVersion = fw.GetHeader().RFChipType;
+    RFVersion = fwheader.RFChipType;
     memset(RFRegs, 0, 4*0x40);
 
-    Firmware::FirmwareConsoleType console = fw.GetHeader().ConsoleType;
+    // load channel index/data from the firmware
+    // the current channel will be determined by RF settings
+    // so we compare the two 'most important' RF registers to these values to figure out which channel is selected
+
+    if (RFVersion == 3)
+    {
+        RFChannelIndex[0] = fwheader.Type3Config.RFIndex1;
+        RFChannelIndex[1] = fwheader.Type3Config.RFIndex2;
+
+        for (int i = 0; i < 14; i++)
+        {
+            RFChannelData[i][0] = fwheader.Type3Config.RFData1[i];
+            RFChannelData[i][1] = fwheader.Type3Config.RFData2[i];
+        }
+    }
+    else
+    {
+        RFChannelIndex[0] = fwheader.Type2Config.InitialRF56Values[2] >> 2;
+        RFChannelIndex[1] = fwheader.Type2Config.InitialRF56Values[5] >> 2;
+
+        for (int i = 0; i < 14; i++)
+        {
+            RFChannelData[i][0] = fwheader.Type2Config.InitialRF56Values[i*6 + 0] |
+                                  (fwheader.Type2Config.InitialRF56Values[i*6 + 1] << 8) |
+                                  ((fwheader.Type2Config.InitialRF56Values[i*6 + 2] & 0x03) << 16);
+            RFChannelData[i][1] = fwheader.Type2Config.InitialRF56Values[i*6 + 3] |
+                                  (fwheader.Type2Config.InitialRF56Values[i*6 + 4] << 8) |
+                                  ((fwheader.Type2Config.InitialRF56Values[i*6 + 5] & 0x03) << 16);
+        }
+    }
+
+    CurChannel = 0;
+
+    Firmware::FirmwareConsoleType console = fwheader.ConsoleType;
     if (console == Firmware::FirmwareConsoleType::DS)
         IOPORT(0x000) = 0x1440;
     else if (console == Firmware::FirmwareConsoleType::DSLite)
@@ -182,6 +216,8 @@ void Wifi::Reset()
     // TODO: find out what the initial values are
     IOPORT(W_PowerUS) = 0x0001;
 
+    //IOPORT(W_BeaconInterval) = 100;
+
     USTimestamp = 0;
 
     USCounter = 0;
@@ -209,7 +245,6 @@ void Wifi::Reset()
     CmdCounter = 0;
 
     USUntilPowerOn = 0;
-    ForcePowerOn = false;
 
     IsMP = false;
     IsMPClient = false;
@@ -244,6 +279,8 @@ void Wifi::DoSavestate(Savestate* file)
     file->Var8(&RFVersion);
     file->VarArray(RFRegs, 4*0x40);
 
+    file->Var32((u32*)&CurChannel);
+
     file->Var64(&USCounter);
     file->Var64(&USCompare);
     file->Bool32(&BlockBeaconIRQ14);
@@ -285,7 +322,6 @@ void Wifi::DoSavestate(Savestate* file)
     file->Var16(&MPLastSeqno);
 
     file->Var32((u32*)&USUntilPowerOn);
-    file->Bool32(&ForcePowerOn);
 
     file->Bool32(&IsMP);
     file->Bool32(&IsMPClient);
@@ -351,33 +387,38 @@ void Wifi::SetPowerCnt(u32 val)
 }
 
 
-void Wifi::SetIRQ(u32 irq)
+void Wifi::CheckIRQ(u16 oldflags)
 {
-    u32 oldflags = IOPORT(W_IF) & IOPORT(W_IE);
-
-    IOPORT(W_IF) |= (1<<irq);
-    u32 newflags = IOPORT(W_IF) & IOPORT(W_IE);
+    u16 newflags = IOPORT(W_IF) & IOPORT(W_IE);
 
     if ((oldflags == 0) && (newflags != 0))
         NDS.SetIRQ(1, IRQ_Wifi);
 }
 
+void Wifi::SetIRQ(u32 irq)
+{
+    u16 oldflags = IOPORT(W_IF) & IOPORT(W_IE);
+
+    IOPORT(W_IF) |= (1<<irq);
+    CheckIRQ(oldflags);
+}
+
 void Wifi::SetIRQ13()
 {
     SetIRQ(13);
 
-    if (!(IOPORT(W_PowerTX) & 0x0002))
+    if ((IOPORT(W_ModeWEP) & 0x7) != 3)
     {
-        IOPORT(0x034) = 0x0002;
-        //PowerDown();
-        // FIXME!!
-        IOPORT(W_RFPins) = 0x0046;
-        IOPORT(W_RFStatus) = 9;
+        if (!(IOPORT(W_PowerTX) & (1<<1)))
+        {
+            UpdatePowerStatus(-1);
+        }
     }
 }
 
 void Wifi::SetIRQ14(int source) // 0=USCOMPARE 1=BEACONCOUNT 2=forced
 {
+    // CHECKME: is this also done for USCOMPARE IRQ?
     if (source != 2)
         IOPORT(W_BeaconCount1) = IOPORT(W_BeaconInterval);
 
@@ -409,10 +450,10 @@ void Wifi::SetIRQ15()
 {
     SetIRQ(15);
 
-    if (IOPORT(W_PowerTX) & 0x0001)
+    // unlike auto sleep, auto wakeup works under all power management modes
+    if (IOPORT(W_PowerTX) & (1<<0))
     {
-        IOPORT(W_RFPins) |= 0x0080;
-        IOPORT(W_RFStatus) = 1;
+        UpdatePowerStatus(1);
     }
 }
 
@@ -426,16 +467,110 @@ void Wifi::SetStatus(u32 status)
 }
 
 
-void Wifi::PowerDown()
+void Wifi::UpdatePowerStatus(int power) // 1=on 0=no change -1=off
 {
-    IOPORT(W_TXReqRead) &= ~0x000F;
-    IOPORT(W_PowerState) |= 0x0200;
+    // TRANSCEIVER POWER MANAGEMENT
+    //
+    // * W_PowerForce overrides all else
+    // * W_ModeReset bit0 forcibly turns off the transceiver when cleared
+    // * power is normally turned on or off either by IRQ15/IRQ13 or by W_PowerState
+    //   depending on the power management mode selected in W_ModeWEP
+    // * W_PowerDownCtrl controls how deep a regular power-down is
 
-    // if the RF hardware is powered down while still sending or receiving,
-    // the current frame is completed before going idle
-    if (!ComStatus)
+    int curflags = 0;
+    if (IOPORT(W_TRXPower) == 1) curflags |= 1;
+    if (!(IOPORT(W_PowerState) & (1<<9))) curflags |= 2;
+    int reqflags = curflags;
+
+    if (IOPORT(W_PowerForce) & (1<<15))
+    {
+        reqflags = (IOPORT(W_PowerForce) & (1<<0)) ? 0 : 3;
+    }
+    else if (!(IOPORT(W_ModeReset) & (1<<0)))
     {
-        SetStatus(9);
+        reqflags = 0;
+    }
+    else
+    {
+        if (power == 0)
+        {
+            if ((IOPORT(W_PowerState) & 0x0202) == 0x0202)
+                power = 1;
+            else if ((IOPORT(W_PowerState) & 0x0201) == 0x0001)
+                power = -1;
+        }
+
+        // W_PowerDownCtrl:
+        // * bit 0 inhibits a regular power-down
+        // * bit 1 forces a wakeup, atleast partial
+
+        if ((power == -1) && (IOPORT(W_PowerDownCtrl) & (1<<0)))
+            power = 0;
+
+        /*if (power == 1)
+            reqflags = 3;
+        else if (power == -1)
+            reqflags = IOPORT(W_PowerDownCtrl);
+        else if (IOPORT(W_PowerDownCtrl) & (1<<1))
+            reqflags = (curflags == 3) ? 3 : IOPORT(W_PowerDownCtrl);*/
+
+        // TODO: support partial power statuses (W_PowerDownCtrl=1 or 2)
+
+        if (power == 1)
+            reqflags = 3;
+        else if (power == -1)
+            reqflags = IOPORT(W_PowerDownCtrl) ? 3 : 0;
+        else if (IOPORT(W_PowerDownCtrl) & (1<<1))
+            reqflags = 3;
+    }
+
+    if (reqflags == curflags)
+        return;
+
+    if (reqflags & 1)
+    {
+        if (!(curflags & 1))
+        {
+            IOPORT(W_TRXPower) = 1;
+            SetStatus(1);
+        }
+    }
+    else
+    {
+        // signal the transceiver is going to turn off (checkme)
+        IOPORT(W_TRXPower) = 2;
+
+        if (!ComStatus)
+        {
+            IOPORT(W_TRXPower) = 0;
+            SetStatus(9);
+        }
+    }
+
+    if (reqflags & 2)
+    {
+        // power on
+
+        IOPORT(W_PowerState) |= (1<<8);
+        if ((!(curflags & 2)) && (USUntilPowerOn == 0))
+        {
+            Log(LogLevel::Debug, "wifi: TRX power ON\n");
+
+            USUntilPowerOn = -2048;
+            SetIRQ(11);
+        }
+    }
+    else
+    {
+        // power off
+
+        if (curflags & 2)
+            Log(LogLevel::Debug, "wifi: TRX power OFF\n");
+
+        IOPORT(W_PowerState) &= ~(1<<0);
+        IOPORT(W_PowerState) &= ~(1<<8);
+        IOPORT(W_PowerState) |= (1<<9);
+        USUntilPowerOn = 0;
     }
 }
 
@@ -521,6 +656,9 @@ void Wifi::TXSendFrame(const TXSlot* slot, int num)
     if (noseqno == 2)
         *(u16*)&TXBuffer[0xC] |= (1<<11);
 
+    if (CurChannel == 0) return;
+    TXBuffer[9] = CurChannel;
+
     switch (num)
     {
     case 0:
@@ -600,6 +738,9 @@ void Wifi::StartTX_Cmd()
         slot->CurPhase = 13;
         slot->CurPhaseTime = CmdCounter - 100;
     }
+
+    // starting a CMD transfer wakes up the transceiver automatically
+    UpdatePowerStatus(1);
 }
 
 void Wifi::StartTX_Beacon()
@@ -678,6 +819,9 @@ void Wifi::SendMPDefaultReply()
     // TODO
     reply[0x8] = 0x14;
 
+    if (CurChannel == 0) return;
+    reply[0x9] = CurChannel;
+
     *(u16*)&reply[0xC + 0x00] = 0x0158;
     *(u16*)&reply[0xC + 0x02] = 0x00F0;//0; // TODO??
     *(u16*)&reply[0xC + 0x04] = IOPORT(W_BSSID0);
@@ -767,6 +911,9 @@ void Wifi::SendMPAck(u16 cmdcount, u16 clientfail)
     if (TXSlots[1].Rate == 2) ack[0x8] = 0x14;
     else                      ack[0x8] = 0xA;
 
+    if (CurChannel == 0) return;
+    ack[0x9] = CurChannel;
+
     *(u16*)&ack[0xC + 0x00] = 0x0218;
     *(u16*)&ack[0xC + 0x02] = 0;
     *(u16*)&ack[0xC + 0x04] = 0x0903;
@@ -1110,8 +1257,11 @@ void Wifi::FinishRX()
 
     if (!ComStatus)
     {
-        if (IOPORT(W_PowerState) & 0x0300)
+        if (IOPORT(W_PowerState) & (1<<9))
+        {
+            IOPORT(W_TRXPower) = 0;
             SetStatus(9);
+        }
         else
             SetStatus(1);
     }
@@ -1380,7 +1530,7 @@ void Wifi::FinishRX()
 
 void Wifi::MPClientReplyRX(int client)
 {
-    if (IOPORT(W_PowerState) & 0x0300)
+    if (IOPORT(W_PowerState) & (1<<9))
         return;
 
     if (!(IOPORT(W_RXCnt) & 0x8000))
@@ -1421,7 +1571,7 @@ void Wifi::MPClientReplyRX(int client)
 
 bool Wifi::CheckRX(int type) // 0=regular 1=MP replies 2=MP host frames
 {
-    if (IOPORT(W_PowerState) & 0x0300)
+    if (IOPORT(W_PowerState) & (1<<9))
         return false;
 
     if (!(IOPORT(W_RXCnt) & 0x8000))
@@ -1433,7 +1583,7 @@ bool Wifi::CheckRX(int type) // 0=regular 1=MP replies 2=MP host frames
     int rxlen;
     int framelen;
     u16 framectl;
-    u8 txrate;
+    u8 txrate, chan;
     u64 timestamp;
 
     for (;;)
@@ -1468,6 +1618,13 @@ bool Wifi::CheckRX(int type) // 0=regular 1=MP replies 2=MP host frames
             continue;
         }
 
+        chan = RXBuffer[9];
+        if (chan != CurChannel || CurChannel == 0)
+        {
+            Log(LogLevel::Debug, "received frame but bad channel %d (expected %d)\n", chan, CurChannel);
+            continue;
+        }
+
         framectl = *(u16*)&RXBuffer[12+0];
         txrate = RXBuffer[8];
 
@@ -1528,7 +1685,6 @@ bool Wifi::CheckRX(int type) // 0=regular 1=MP replies 2=MP host frames
         // we also need to determine how far we can run after having received this frame
 
         RXTimestamp = timestamp;
-        //if (RXTimestamp < USTimestamp) printf("CRAP!! %04X %016llX %016llX\n", framectl, RXTimestamp, USTimestamp);
         if (RXTimestamp < USTimestamp) RXTimestamp = USTimestamp;
         NextSync = RXTimestamp + (framelen * (txrate==0x14 ? 4:8));
 
@@ -1570,11 +1726,13 @@ void Wifi::MSTimer()
         }
     }
 
-    IOPORT(W_BeaconCount1)--;
-    if (IOPORT(W_BeaconCount1) == 0)
+    if (IOPORT(W_BeaconCount1) != 0)
     {
-        SetIRQ14(1);
+        IOPORT(W_BeaconCount1)--;
+        if (IOPORT(W_BeaconCount1) == 0) SetIRQ14(1);
     }
+    if (IOPORT(W_BeaconCount1) == 0)
+        IOPORT(W_BeaconCount1) = IOPORT(W_BeaconInterval);
 
     if (IOPORT(W_BeaconCount2) != 0)
     {
@@ -1605,19 +1763,19 @@ void Wifi::USTimer(u32 param)
     if (!(USTimestamp & 0x3FF & kTimeCheckMask))
         WifiAP->MSTimer();
 
-    bool switchOffPowerSaving = false;
     if (USUntilPowerOn < 0)
     {
         USUntilPowerOn += kTimerInterval;
 
-        switchOffPowerSaving = (USUntilPowerOn >= 0) && (IOPORT(W_PowerUnk) & 0x0001 || ForcePowerOn);
-    }
-    if ((USUntilPowerOn >= 0) && (IOPORT(W_PowerState) & 0x0002 || switchOffPowerSaving))
-    {
-        IOPORT(W_PowerState) = 0;
-        IOPORT(W_RFPins) = 1;
-        IOPORT(W_RFPins) = 0x0084;
-        SetIRQ(11);
+        if (USUntilPowerOn >= 0)
+        {
+            USUntilPowerOn = 0;
+
+            IOPORT(W_PowerState) = 0;
+            SetStatus(1);
+
+            UpdatePowerStatus(0);
+        }
     }
 
     if (IOPORT(W_USCountCnt))
@@ -1660,7 +1818,7 @@ void Wifi::USTimer(u32 param)
         u16 txbusy = IOPORT(W_TXBusy);
         if (txbusy)
         {
-            if (IOPORT(W_PowerState) & 0x0300)
+            if (IOPORT(W_PowerState) & (1<<9))
             {
                 ComStatus = 0;
                 TXCurSlot = -1;
@@ -1695,9 +1853,10 @@ void Wifi::USTimer(u32 param)
         bool finished = ProcessTX(&TXSlots[TXCurSlot], TXCurSlot);
         if (finished)
         {
-            if (IOPORT(W_PowerState) & 0x0300)
+            if (IOPORT(W_PowerState) & (1<<9))
             {
                 IOPORT(W_TXBusy) = 0;
+                IOPORT(W_TRXPower) = 0;
                 SetStatus(9);
             }
 
@@ -1754,8 +1913,9 @@ void Wifi::USTimer(u32 param)
                     RXCounter = 0;
                 }
                 // TODO: proper error management
-                if ((!ComStatus) && (IOPORT(W_PowerState) & 0x0300))
+                if ((!ComStatus) && (IOPORT(W_PowerState) & (1<<9)))
                 {
+                    IOPORT(W_TRXPower) = 0;
                     SetStatus(9);
                 }
             }
@@ -1766,6 +1926,28 @@ void Wifi::USTimer(u32 param)
 }
 
 
+void Wifi::ChangeChannel()
+{
+    u32 val1 = RFRegs[RFChannelIndex[0]];
+    u32 val2 = RFRegs[RFChannelIndex[1]];
+
+    CurChannel = 0;
+
+    for (int i = 0; i < 14; i++)
+    {
+        if (val1 == RFChannelData[i][0] && val2 == RFChannelData[i][1])
+        {
+            CurChannel = i+1;
+            break;
+        }
+    }
+
+    if (CurChannel > 0)
+        Log(LogLevel::Debug, "wifi: switching to channel %d\n", CurChannel);
+    else
+        Log(LogLevel::Debug, "wifi: invalid channel values %05X:%05X\n", val1, val2);
+}
+
 void Wifi::RFTransfer_Type2()
 {
     u32 id = (IOPORT(W_RFData2) >> 2) & 0x1F;
@@ -1780,6 +1962,9 @@ void Wifi::RFTransfer_Type2()
     {
         u32 data = IOPORT(W_RFData1) | ((IOPORT(W_RFData2) & 0x0003) << 16);
         RFRegs[id] = data;
+
+        if (id == RFChannelIndex[0] || id == RFChannelIndex[1])
+            ChangeChannel();
     }
 }
 
@@ -1796,6 +1981,9 @@ void Wifi::RFTransfer_Type3()
     {
         u32 data = IOPORT(W_RFData1) & 0xFF;
         RFRegs[id] = data;
+
+        if (id == RFChannelIndex[0] || id == RFChannelIndex[1])
+            ChangeChannel();
     }
 }
 
@@ -1819,6 +2007,7 @@ u16 Wifi::Read(u32 addr)
     switch (addr)
     {
     case W_Random: // random generator. not accurate
+        // TODO: rotate the sequence based on the ARM7 cycle counter (if this is important)
         Random = (Random & 0x1) ^ (((Random & 0x3FF) << 1) | (Random >> 10));
         return Random;
 
@@ -1899,7 +2088,6 @@ u16 Wifi::Read(u32 addr)
         }
     }
 
-    //printf("WIFI: read %08X\n", addr);
     return IOPORT(addr&0xFFF);
 }
 
@@ -1923,28 +2111,20 @@ void Wifi::Write(u32 addr, u16 val)
     case W_ModeReset:
         {
             u16 oldval = IOPORT(W_ModeReset);
+            IOPORT(W_ModeReset) = val & 0x0001;
 
             if (!(oldval & 0x0001) && (val & 0x0001))
             {
-                if (!(USUntilPowerOn < 0 && ForcePowerOn))
-                {
-                    //printf("mode reset power on %08x\n", NDS::ARM7->R[15]);
-                    IOPORT(0x034) = 0x0002;
-                    IOPORT(0x27C) = 0x0005;
-                    // TODO: 02A2??
+                IOPORT(0x27C) = 0x0005;
+                // TODO: 02A2??
 
-                    if (IOPORT(W_PowerUnk) & 0x0002)
-                    {
-                        USUntilPowerOn = -2048;
-                        IOPORT(W_PowerState) |= 0x100;
-                    }
-                }
+                UpdatePowerStatus(0);
             }
             else if ((oldval & 0x0001) && !(val & 0x0001))
             {
-                //printf("mode reset shutdown %08x\n", NDS::ARM7->R[15]);
                 IOPORT(0x27C) = 0x000A;
-                PowerDown();
+
+                UpdatePowerStatus(0);
             }
 
             if (val & 0x2000)
@@ -1986,23 +2166,43 @@ void Wifi::Write(u32 addr, u16 val)
                 IOPORT(0x230) = 0x0047;
             }
         }
-        break;
+        return;
 
     case W_ModeWEP:
         val &= 0x007F;
-        //printf("writing mode web %x\n", val);
-        if ((val & 0x7) == 1)
-            IOPORT(W_PowerUnk) |= 0x0002;
-        if ((val & 0x7) == 2)
-            IOPORT(W_PowerUnk) = 0x0003;
-        break;
+        IOPORT(W_ModeWEP) = val;
+
+        if (IOPORT(W_PowerTX) & (1<<1))
+        {
+            if ((val & 0x7) == 1)
+                IOPORT(W_PowerDownCtrl) |= (1<<1);
+            else if ((val & 0x7) == 2)
+                IOPORT(W_PowerDownCtrl) = 3;
+
+            if ((val & 0x7) != 3)
+                IOPORT(W_PowerState) &= 0x0300;
 
+            UpdatePowerStatus(0);
+        }
+        return;
+
+    case W_IE:
+        {
+            u16 oldflags = IOPORT(W_IF) & IOPORT(W_IE);
+            IOPORT(W_IE) = val;
+            CheckIRQ(oldflags);
+        }
+        return;
     case W_IF:
         IOPORT(W_IF) &= ~val;
         return;
     case W_IFSet:
-        IOPORT(W_IF) |= (val & 0xFBFF);
-        Log(LogLevel::Debug, "wifi: force-setting IF %04X\n", val);
+        {
+            u16 oldflags = IOPORT(W_IF) & IOPORT(W_IE);
+            IOPORT(W_IF) |= (val & 0xFBFF);
+            CheckIRQ(oldflags);
+            Log(LogLevel::Debug, "wifi: force-setting IF %04X\n", val);
+        }
         return;
 
     case W_AIDLow:
@@ -2012,67 +2212,63 @@ void Wifi::Write(u32 addr, u16 val)
         IOPORT(W_AIDFull) = val & 0x07FF;
         return;
 
-    case W_PowerState:
-        //printf("writing power state %x %08x\n", val, NDS::ARM7->R[15]);
-        IOPORT(W_PowerState) |= val & 0x0002;
+    case W_PowerUS:
+        IOPORT(W_PowerUS) = val & 0x0003;
+        UpdatePowerOn();
+        return;
 
-        if (IOPORT(W_ModeReset) & 0x0001 && IOPORT(W_PowerState) & 0x0002)
+    case W_PowerTX:
+        IOPORT(W_PowerTX) = val & 0x0003;
+        if (val & (1<<1))
         {
-            /*if (IOPORT(W_PowerState) & 0x100)
-            {
-                AlwaysPowerOn = true;
-                USUntilPowerOn = -1;
-            }
-            else */
-            if (IOPORT(W_PowerForce) == 1)
-            {
-                //printf("power on\n");
-                IOPORT(W_PowerState) |= 0x100;
-                USUntilPowerOn = -2048;
-                ForcePowerOn = false;
-            }
+            if ((IOPORT(W_ModeWEP) & 0x7) == 1)
+                IOPORT(W_PowerDownCtrl) |= (1<<1);
+            else if ((IOPORT(W_ModeWEP) & 0x7) == 2)
+                IOPORT(W_PowerDownCtrl) = 3;
+
+            UpdatePowerStatus(0);
         }
         return;
-    case W_PowerForce:
-        //if ((val&0x8001)==0x8000) printf("WIFI: forcing power %04X\n", val);
 
+    case W_PowerState:
+        if ((IOPORT(W_ModeWEP) & 0x7) != 3)
+            return;
+
+        val = (IOPORT(W_PowerState) & 0x0300) | (val & 0x0003);
+        if ((val & 0x0300) == 0x0200)
+            val &= ~(1<<0);
+        else
+            val &= ~(1<<1);
+
+        if (!(val & (1<<9)))
+            val &= ~(1<<8);
+
+        IOPORT(W_PowerState) = val;
+        UpdatePowerStatus(0);
+        return;
+
+    case W_PowerForce:
         val &= 0x8001;
-        //printf("writing power force %x %08x\n", val, NDS::ARM7->R[15]);
-        if (val == 0x8001)
-        {
-            //printf("force power off\n");
-            IOPORT(0x034) = 0x0002;
-            IOPORT(W_PowerState) = 0x0200;
-            IOPORT(W_TXReqRead) = 0;
-            PowerDown();
-        }
-        if (val == 1 && IOPORT(W_PowerState) & 0x0002)
-        {
-            //printf("power on\n");
-            IOPORT(W_PowerState) |= 0x100;
-            USUntilPowerOn = -2048;
-            ForcePowerOn = false;
-        }
-        if (val == 0x8000)
+        IOPORT(W_PowerForce) = val;
+        UpdatePowerStatus(0);
+        return;
+
+    case W_PowerDownCtrl:
+        IOPORT(W_PowerDownCtrl) = val & 0x0003;
+
+        if (IOPORT(W_PowerTX) & (1<<1))
         {
-            //printf("force power on\n");
-            IOPORT(W_PowerState) |= 0x100;
-            USUntilPowerOn = -2048;
-            ForcePowerOn = true;
+            if ((IOPORT(W_ModeWEP) & 0x7) == 1)
+                IOPORT(W_PowerDownCtrl) |= (1<<1);
+            else if ((IOPORT(W_ModeWEP) & 0x7) == 2)
+                IOPORT(W_PowerDownCtrl) = 3;
         }
-        break;
-    case W_PowerUS:
-        IOPORT(W_PowerUS) = val & 0x0003;
-        UpdatePowerOn();
+        
+        if (val != 0 && val != 3)
+            Log(LogLevel::Warn, "wifi: unusual W_PowerDownCtrl value %04X\n", val);
+
+        UpdatePowerStatus(0);
         return;
-    case W_PowerUnk:
-        val &= 0x0003;
-        //printf("writing power unk %x\n", val);
-        if ((IOPORT(W_ModeWEP) & 0x7) == 1)
-            val |= 2;
-        else if ((IOPORT(W_ModeWEP) & 0x7) == 2)
-            val = 3;
-        break;
 
     case W_USCountCnt: val &= 0x0001; break;
     case W_USCompareCnt:
@@ -2231,6 +2427,7 @@ void Wifi::Write(u32 addr, u16 val)
 
     // read-only ports
     case 0x000:
+    case 0x034:
     case 0x044:
     case 0x054:
     case 0x098:
diff --git a/src/Wifi.h b/src/Wifi.h
index 5553a6f..2e0465a 100644
--- a/src/Wifi.h
+++ b/src/Wifi.h
@@ -52,11 +52,12 @@ public:
         W_RXCnt = 0x030,
         W_WEPCnt = 0x032,
 
+        W_TRXPower = 0x034,
         W_PowerUS = 0x036,
         W_PowerTX = 0x038,
         W_PowerState = 0x03C,
         W_PowerForce = 0x040,
-        W_PowerUnk = 0x48,
+        W_PowerDownCtrl = 0x48,
 
         W_Random = 0x044,
 
@@ -206,6 +207,10 @@ private:
     u8 RFVersion;
     u32 RFRegs[0x40];
 
+    u32 RFChannelIndex[2];
+    u32 RFChannelData[14][2];
+    int CurChannel;
+
     struct TXSlot
     {
         bool Valid;
@@ -240,7 +245,6 @@ private:
     bool LANInited;
 
     int USUntilPowerOn;
-    bool ForcePowerOn;
 
     // MULTIPLAYER SYNC APPARATUS
     bool IsMP;
@@ -253,13 +257,15 @@ private:
     void ScheduleTimer(bool first);
     void UpdatePowerOn();
 
+    void CheckIRQ(u16 oldflags);
     void SetIRQ(u32 irq);
     void SetIRQ13();
     void SetIRQ14(int source);
     void SetIRQ15();
 
     void SetStatus(u32 status);
-    void PowerDown();
+
+    void UpdatePowerStatus(int power);
 
     int PreambleLen(int rate) const;
     u32 NumClients(u16 bitmask) const;
@@ -284,6 +290,8 @@ private:
 
     void MSTimer();
 
+    void ChangeChannel();
+
     void RFTransfer_Type2();
     void RFTransfer_Type3();
 };
diff --git a/src/WifiAP.cpp b/src/WifiAP.cpp
index 4c64520..855dc24 100644
--- a/src/WifiAP.cpp
+++ b/src/WifiAP.cpp
@@ -35,6 +35,7 @@ using Platform::LogLevel;
 
 const char* WifiAP::APName = "melonAP";
 const u8 WifiAP::APMac[6] = {0x00, 0xF0, 0x77, 0x77, 0x77, 0x77};
+const u8 WifiAP::APChannel = 6;
 
 #define PWRITE_8(p, v)      *p++ = v;
 #define PWRITE_16(p, v)     *(u16*)p = v; p += 2;
@@ -55,7 +56,7 @@ const u8 WifiAP::APMac[6] = {0x00, 0xF0, 0x77, 0x77, 0x77, 0x77};
     PWRITE_16(p, 0); \
     PWRITE_16(p, 0); \
     PWRITE_8(p, rate); \
-    PWRITE_8(p, 0); \
+    PWRITE_8(p, APChannel); \
     PWRITE_16(p, len);
 
 //#define PALIGN_4(p, base)  p += ((4 - ((ptrdiff_t)(p-base) & 0x3)) & 0x3);
@@ -174,7 +175,7 @@ int WifiAP::HandleManagementFrame(const u8* data, int len)
             PWRITE_16(p, 128); // beacon interval
             PWRITE_16(p, 0x0021); // capability
             PWRITE_8(p, 0x01); PWRITE_8(p, 0x02); PWRITE_8(p, 0x82); PWRITE_8(p, 0x84); // rates
-            PWRITE_8(p, 0x03); PWRITE_8(p, 0x01); PWRITE_8(p, 0x06); // current channel
+            PWRITE_8(p, 0x03); PWRITE_8(p, 0x01); PWRITE_8(p, APChannel); // current channel
             PWRITE_8(p, 0x00); PWRITE_8(p, strlen(APName));
             memcpy(p, APName, strlen(APName)); p += strlen(APName);
 
@@ -260,6 +261,9 @@ int WifiAP::HandleManagementFrame(const u8* data, int len)
 
 int WifiAP::SendPacket(const u8* data, int len)
 {
+    if (data[9] != APChannel)
+        return 0;
+
     data += 12;
 
     u16 framectl = *(u16*)&data[0];
@@ -327,7 +331,7 @@ int WifiAP::RecvPacket(u8* data)
         PWRITE_16(p, 128); // beacon interval
         PWRITE_16(p, 0x0021); // capability
         PWRITE_8(p, 0x01); PWRITE_8(p, 0x02); PWRITE_8(p, 0x82); PWRITE_8(p, 0x84); // rates
-        PWRITE_8(p, 0x03); PWRITE_8(p, 0x01); PWRITE_8(p, 0x06); // current channel
+        PWRITE_8(p, 0x03); PWRITE_8(p, 0x01); PWRITE_8(p, APChannel); // current channel
         PWRITE_8(p, 0x05); PWRITE_8(p, 0x04); PWRITE_8(p, 0); PWRITE_8(p, 0); PWRITE_8(p, 0); PWRITE_8(p, 0); // TIM
         PWRITE_8(p, 0x00); PWRITE_8(p, strlen(APName));
         memcpy(p, APName, strlen(APName)); p += strlen(APName);
diff --git a/src/WifiAP.h b/src/WifiAP.h
index 8f3ed11..a9e80c3 100644
--- a/src/WifiAP.h
+++ b/src/WifiAP.h
@@ -34,6 +34,7 @@ public:
 
     static const char* APName;
     static const u8 APMac[6];
+    static const u8 APChannel;
 
     void MSTimer();
 
diff --git a/src/frontend/qt_sdl/Window.cpp b/src/frontend/qt_sdl/Window.cpp
index fde29b6..23ba784 100644
--- a/src/frontend/qt_sdl/Window.cpp
+++ b/src/frontend/qt_sdl/Window.cpp
@@ -805,7 +805,7 @@ void MainWindow::keyPressEvent(QKeyEvent* event)
     if (event->isAutoRepeat()) return;
 
     // TODO!! REMOVE ME IN RELEASE BUILDS!!
-    //if (event->key() == Qt::Key_F11) NDS::debug(0);
+    //if (event->key() == Qt::Key_F11) emuThread->NDS->debug(0);
 
     Input::KeyPress(event);
 }