/**
* Take into account the Falcon Bus Control register $ff8007.b
$FFFF8007 Falcon Bus Control
BIT 6 : F30 Start (0=Cold, 1=Warm)
BIT 5 : STe Bus Emulation (0=on)
BIT 3 : Blitter Flag (0=on, 1=off)
BIT 2 : Blitter (0=8mhz, 1=16mhz)
BIT 0 : 68030 (0=8mhz, 1=16mhz)
*/
static void IoMemTabFalcon_BusCtrl_WriteByte(void)
{
Uint8 busCtrl = IoMem_ReadByte(0xff8007);
/* Set Falcon bus or STE compatible bus emulation */
if ((busCtrl & 0x20) == 0)
IoMem_Init_FalconInSTeBuscompatibilityMode(0);
else
IoMem_Init_FalconInSTeBuscompatibilityMode(1);
/* 68030 Frequency changed ? */
/* We change freq only in 68030 mode for a normal Falcon, */
/* not if CPU is 68040 or 68060 is used */
if ( ConfigureParams.System.nCpuLevel == 3 )
{
if ((busCtrl & 0x1) == 1) {
/* 16 Mhz bus for 68030 */
nCpuFreqShift = 1;
ConfigureParams.System.nCpuFreq = 16;
}
else {
/* 8 Mhz bus for 68030 */
nCpuFreqShift = 0;
ConfigureParams.System.nCpuFreq = 8;
}
}
Statusbar_UpdateInfo(); /* Update clock speed in the status bar */
}
bool DSP_ProcessIRQ(void)
{
if (bDspHostInterruptPending && regs.intmask < 6)
{
M68000_Exception(IoMem_ReadByte(0xffa203)*4, M68000_EXC_SRC_INT_DSP);
bDspHostInterruptPending = false;
// M68000_UnsetSpecial(SPCFLAG_DSP);
return true;
}
return false;
}
/**
* Write to RTC/NVRAM offset selection register ($ff8961)
*/
void NvRam_Select_WriteByte(void)
{
Uint8 value = IoMem_ReadByte(0xff8961);
if (value < sizeof(nvram))
{
nvram_index = value;
}
else
{
Log_Printf(LOG_WARN, "NVRAM: trying to set out-of-bound position (%d)\n", value);
}
}
/**
* Set default memory configuration, connected floppies, memory size and
* clear the ST-RAM area.
* As TOS checks hardware for memory size + connected devices on boot-up
* we set these values ourselves and fill in the magic numbers so TOS
* skips these tests.
*/
void STMemory_SetDefaultConfig(void)
{
int i;
int screensize, limit;
int memtop, phystop;
Uint8 nMemControllerByte;
Uint8 nFalcSysCntrl;
static const int MemControllerTable[] =
{
0x01, /* 512 KiB */
0x05, /* 1 MiB */
0x02, /* 2 MiB */
0x06, /* 2.5 MiB */
0x0A /* 4 MiB */
};
if (bRamTosImage)
{
/* Clear ST-RAM, excluding the RAM TOS image */
STMemory_Clear(0x00000000, TosAddress);
STMemory_Clear(TosAddress+TosSize, STRamEnd);
}
else
{
/* Clear whole ST-RAM */
STMemory_Clear(0x00000000, STRamEnd);
}
/* Mirror ROM boot vectors */
STMemory_WriteLong(0x00, STMemory_ReadLong(TosAddress));
STMemory_WriteLong(0x04, STMemory_ReadLong(TosAddress+4));
/* Fill in magic numbers to bypass TOS' memory tests for faster boot or
* if VDI resolution is enabled or if more than 4 MB of ram are used
* or if TT RAM added in Falcon mode.
* (for highest compatibility, those tests should not be bypassed in
* the common STF/STE cases as some programs like "Yolanda" rely on
* the RAM content after those tests) */
if ( ConfigureParams.System.bFastBoot
|| bUseVDIRes
|| ( ConfigureParams.Memory.nMemorySize > 4 && !bIsEmuTOS )
|| ( ( ConfigureParams.System.nMachineType == MACHINE_FALCON ) && TTmemory ) )
{
/* Write magic values to sysvars to signal valid config */
STMemory_WriteLong(0x420, 0x752019f3); /* memvalid */
STMemory_WriteLong(0x43a, 0x237698aa); /* memval2 */
STMemory_WriteLong(0x51a, 0x5555aaaa); /* memval3 */
/* If ST RAM detection is bypassed, we must also force TT RAM config if enabled */
if ( TTmemory )
STMemory_WriteLong ( 0x5a4 , 0x01000000 + TTmem_size ); /* ramtop */
else
STMemory_WriteLong ( 0x5a4 , 0 ); /* ramtop */
STMemory_WriteLong ( 0x5a8 , 0x1357bd13 ); /* ramvalid */
/* On Falcon, set bit6=1 at $ff8007 to simulate a warm start */
/* (else memory detection is not skipped after a cold start/reset) */
if ( ConfigureParams.System.nMachineType == MACHINE_FALCON )
STMemory_WriteByte ( 0xff8007, IoMem_ReadByte(0xff8007) | 0x40 );
/* On TT, set bit0=1 at $ff8e09 to simulate a warm start */
/* (else memory detection is not skipped after a cold start/reset) */
if ( ConfigureParams.System.nMachineType == MACHINE_TT )
STMemory_WriteByte ( 0xff8e09, IoMem_ReadByte(0xff8e09) | 0x01 );
}
/* Set memory size, adjust for extra VDI screens if needed. */
screensize = VDIWidth * VDIHeight / 8 * VDIPlanes;
/* Use 32 kiB in normal screen mode or when the screen size is smaller than 32 kiB */
if (!bUseVDIRes || screensize < 0x8000)
screensize = 0x8000;
/* mem top - upper end of user memory (right before the screen memory)
* memtop / phystop must be dividable by 512 or TOS crashes */
memtop = (STRamEnd - screensize) & 0xfffffe00;
/* phys top - 32k gap causes least issues with apps & TOS
* as that's the largest _common_ screen size. EmuTOS behavior
* depends on machine type.
*
* TODO: what to do about _native_ TT & Videl resolutions
* which size is >32k? Should memtop be adapted also for
* those?
*/
switch (ConfigureParams.System.nMachineType)
{
case MACHINE_FALCON:
/* TOS v4 doesn't work with VDI mode (yet), and
* EmuTOS works with correct gap, so use that */
phystop = STRamEnd;
break;
case MACHINE_TT:
/* For correct TOS v3 memory detection, phystop should be
* at the end of memory, not at memtop + 32k.
*
* However:
* - TOS v3 crashes/hangs if phystop-memtop gap is larger
* than largest real HW screen size (150k)
* - NVDI hangs if gap is larger than 32k in any other than
* monochrome mode
*/
if (VDIPlanes == 1)
limit = 1280*960/8;
else
limit = 0x8000;
if (screensize > limit)
{
phystop = memtop + limit;
fprintf(stderr, "WARNING: too large VDI mode for TOS v3 memory detection to work correctly!\n");
}
else
phystop = STRamEnd;
break;
default:
phystop = memtop + 0x8000;
}
STMemory_WriteLong(0x436, memtop);
STMemory_WriteLong(0x42e, phystop);
if (bUseVDIRes)
fprintf(stderr, "VDI mode memtop: 0x%x, phystop: 0x%x (screensize: %d kB, memtop->phystop: %d kB)\n",
memtop, phystop, (screensize+511) / 1024, (phystop-memtop+511) / 1024);
/* Set memory controller byte according to different memory sizes */
/* Setting per bank: %00=128k %01=512k %10=2Mb %11=reserved. - e.g. %1010 means 4Mb */
if (ConfigureParams.Memory.nMemorySize <= 4)
nMemControllerByte = MemControllerTable[ConfigureParams.Memory.nMemorySize];
else
nMemControllerByte = 0x0f;
STMemory_WriteByte(0x424, nMemControllerByte);
IoMem_WriteByte(0xff8001, nMemControllerByte);
if (ConfigureParams.System.nMachineType == MACHINE_FALCON)
{
/* Set the Falcon memory and monitor configuration register:
$ffff8006.b [R] 76543210 Monitor-memory
||||||||
|||||||+- RAM Wait Status
||||||| 0 = 1 Wait (default)
||||||| 1 = 0 Wait
||||||+-- Video Bus size ???
|||||| 0 = 16 Bit
|||||| 1 = 32 Bit (default)
||||++--- ROM Wait Status
|||| 00 = Reserved
|||| 01 = 2 Wait (default)
|||| 10 = 1 Wait
|||| 11 = 0 Wait
||++----- Falcon Memory
|| 00 = 1 MB
|| 01 = 4 MB
|| 10 = 14 MB
|| 11 = no boot !
++------- Monitor-Typ
00 - Monochrome (SM124)
01 - Color (SC1224)
10 - VGA Color
11 - Television
Bit 1 seems not to be well documented. It's used by TOS at bootup to compute the memory size.
After some tests, I get the following RAM values (Bits 5, 4, 1 are involved) :
00 = 512 Ko 20 = 8192 Ko
02 = 1024 Ko 22 = 14366 Ko
10 = 2048 Ko 30 = Illegal
12 = 4096 Ko 32 = Illegal
I use these values for Hatari's emulation.
I also set the bit 3 and 2 at value 01 are mentioned in the register description.
*/
if (ConfigureParams.Memory.nMemorySize == 14) /* 14 Meg */
nFalcSysCntrl = 0x26;
else if (ConfigureParams.Memory.nMemorySize == 8) /* 8 Meg */
nFalcSysCntrl = 0x24;
else if (ConfigureParams.Memory.nMemorySize == 4) /* 4 Meg */
nFalcSysCntrl = 0x16;
else if (ConfigureParams.Memory.nMemorySize == 2) /* 2 Meg */
nFalcSysCntrl = 0x14;
else if (ConfigureParams.Memory.nMemorySize == 1) /* 1 Meg */
nFalcSysCntrl = 0x06;
else
nFalcSysCntrl = 0x04; /* 512 Ko */
switch(ConfigureParams.Screen.nMonitorType) {
case MONITOR_TYPE_TV:
nFalcSysCntrl |= FALCON_MONITOR_TV;
break;
case MONITOR_TYPE_VGA:
nFalcSysCntrl |= FALCON_MONITOR_VGA;
break;
case MONITOR_TYPE_RGB:
nFalcSysCntrl |= FALCON_MONITOR_RGB;
break;
case MONITOR_TYPE_MONO:
nFalcSysCntrl |= FALCON_MONITOR_MONO;
break;
}
STMemory_WriteByte(0xff8006, nFalcSysCntrl);
}
/* Set TOS floppies */
STMemory_WriteWord(0x446, nBootDrive); /* Boot up on A(0) or C(2) */
/* Create connected drives mask (only for harddrives, don't change floppy drive detected by TOS) */
ConnectedDriveMask = STMemory_ReadLong(0x4c2); // Get initial drive mask (see what TOS thinks)
if (GEMDOS_EMU_ON)
{
for (i = 0; i < MAX_HARDDRIVES; i++)
{
if (emudrives[i] != NULL) // Is this GEMDOS drive enabled?
ConnectedDriveMask |= (1 << emudrives[i]->drive_number);
}
}
/* Set connected drives system variable.
* NOTE: some TOS images overwrite this value, see 'OpCode_SysInit', too */
STMemory_WriteLong(0x4c2, ConnectedDriveMask);
}
void NvRam_Data_WriteByte(void)
{
Uint8 value = IoMem_ReadByte(0xff8963);
LOG_TRACE(TRACE_NVRAM, "NVRAM: write data at %d = %d ($%02x)\n", nvram_index, value, value);
nvram[nvram_index] = value;
}
