src/memory.c

Tue, 21 May 2013 22:48:32 +0100

author
Philip Pemberton <philpem@philpem.me.uk>
date
Tue, 21 May 2013 22:48:32 +0100
branch
experimental_memory_mapper_v2
changeset 145
2d6de28c6e6c
parent 144
609707511166
permissions
-rw-r--r--

Code clean up

* Tighten optimisation and warning options to find more potential issues
* Remove unused variable in keyboard code
* Display error message if ROMs fail to load
* Fix format string bugs in WD2010

     1 #include <stdio.h>
     2 #include <stdlib.h>
     3 #include <stdint.h>
     4 #include <stdbool.h>
     5 #include <assert.h>
     6 #include "musashi/m68k.h"
     7 #include "state.h"
     8 #include "utils.h"
     9 #include "memory.h"
    11 // The value which will be returned if the CPU attempts to read from empty memory
    12 // TODO (FIXME?) - need to figure out if R/W ops wrap around. This seems to appease the UNIX kernel and P4TEST.
    13 #define EMPTY 0xFFFFFFFFUL
    14 //#define EMPTY 0x55555555UL
    15 //#define EMPTY 0x00000000UL
    17 /******************
    18  * Memory mapping
    19  ******************/
    21 /// Set a page bit
    22 #define MAP_SET_PAGEBIT(addr, bit) state.map[(MAP_ADDR_TO_PAGE(addr))*2] |=  ((uint8_t)bit << 2)
    23 /// Clear a page bit
    24 #define MAP_CLR_PAGEBIT(addr, bit) state.map[(MAP_ADDR_TO_PAGE(addr))*2] &= ~((uint8_t)bit << 2)
    27 /********************************************************
    28  * m68k memory read/write support functions for Musashi
    29  ********************************************************/
    31 /**
    32  * @brief	Check memory access permissions for a write operation.
    33  * @note	This used to be a single macro (merged with ACCESS_CHECK_RD), but
    34  * 			gcc throws warnings when you have a return-with-value in a void
    35  * 			function, even if the return-with-value is completely unreachable.
    36  * 			Similarly it doesn't like it if you have a return without a value
    37  * 			in a non-void function, even if it's impossible to ever reach the
    38  * 			return-with-no-value. UGH!
    39  */
    40 /*{{{ macro: ACCESS_CHECK_WR(address, bits)*/
    41 #define ACCESS_CHECK_WR(address, bits)								\
    42 	do {															\
    43 		if (access_check_cpu(address, bits, true)) {				\
    44 			return;													\
    45 		}															\
    46 	} while (0)
    47 /*}}}*/
    49 /**
    50  * @brief Check memory access permissions for a read operation.
    51  * @note	This used to be a single macro (merged with ACCESS_CHECK_WR), but
    52  * 			gcc throws warnings when you have a return-with-value in a void
    53  * 			function, even if the return-with-value is completely unreachable.
    54  * 			Similarly it doesn't like it if you have a return without a value
    55  * 			in a non-void function, even if it's impossible to ever reach the
    56  * 			return-with-no-value. UGH!
    57  */
    58 /*{{{ macro: ACCESS_CHECK_RD(address, bits)*/
    59 #define ACCESS_CHECK_RD(address, bits)								\
    60 	do {															\
    61 		if (access_check_cpu(address, bits, false)) {				\
    62 			if (bits == 32)											\
    63 				return EMPTY & 0xFFFFFFFF;							\
    64 			else													\
    65 				return EMPTY & ((1UL << bits)-1);					\
    66 		}															\
    67 	} while (0)
    68 /*}}}*/
    71 /**
    72  * Update the page bits for a given memory address
    73  *
    74  * @param	addr	Memory address being accessed
    75  * @param	l7intr	Set to <i>true</i> if a level-seven interrupt has been
    76  * 					signalled (even if <b>ENABLE ERROR</b> isn't set).
    77  * @param	write	Set to <i>true</i> if the address is being written to.
    78  */
    79 static void update_page_bits(uint32_t addr, bool l7intr, bool write)
    80 {
    81 	bool ps0_state = false;
    83 	// Don't try and update pagebits for non-RAM addresses
    84 	if (addr > 0x3FFFFF)
    85 		return;
    87 	if (l7intr) {
    88 //		if (!(MAP_PAGEBITS(addr) & PAGE_BIT_PS0)) {
    89 			// FIXME FUCKUP The ruddy TRM is wrong AGAIN! If above line is uncommented, Really Bad Things Happen.
    90 		if ((MAP_PAGEBITS(addr) & PAGE_BIT_PS0)) {
    91 			// Level 7 interrupt, PS0 set, PS1 don't-care. Set PS0.
    92 			ps0_state = true;
    93 		}
    94 	} else {
    95 		// No L7 interrupt
    96 		if ((write && !(MAP_PAGEBITS(addr) & PAGE_BIT_PS1) &&  (MAP_PAGEBITS(addr) & PAGE_BIT_PS0)) ||
    97 			(write &&  (MAP_PAGEBITS(addr) & PAGE_BIT_PS1) && !(MAP_PAGEBITS(addr) & PAGE_BIT_PS0)) ||
    98 			(          (MAP_PAGEBITS(addr) & PAGE_BIT_PS1) &&  (MAP_PAGEBITS(addr) & PAGE_BIT_PS0)))  /* NOTE -- Once again, this case was missing from the PAL equations in the TRM... */
    99 		{
   100 			// No L7 interrupt, PS[1:0] = 0b01, write
   101 			// No L7 interrupt, PS[1:0] = 0b10, write
   102 			ps0_state = true;
   103 		}
   104 	}
   106 #ifdef MAPRAM_BIT_TEST
   107 	LOG("Starting Mapram Bit Test");
   108 	state.map[0] = state.map[1] = 0;
   109 	LOG("Start   = %04X %02X", MAPRAM_ADDR(0), MAP_PAGEBITS(0));
   110 	MAP_SET_PAGEBIT(0, PAGE_BIT_WE);
   111 	LOG("Set WE  = %04X %02X", MAPRAM_ADDR(0), MAP_PAGEBITS(0));
   112 	MAP_SET_PAGEBIT(0, PAGE_BIT_PS1);
   113 	LOG("Set PS1 = %04X %02X", MAPRAM_ADDR(0), MAP_PAGEBITS(0));
   114 	MAP_SET_PAGEBIT(0, PAGE_BIT_PS0);
   115 	LOG("Set PS0 = %04X %02X", MAPRAM_ADDR(0), MAP_PAGEBITS(0));
   117 	MAP_CLR_PAGEBIT(0, PAGE_BIT_WE);
   118 	LOG("Clr WE  = %04X %02X", MAPRAM_ADDR(0), MAP_PAGEBITS(0));
   119 	MAP_CLR_PAGEBIT(0, PAGE_BIT_PS1);
   120 	LOG("Clr PS1 = %04X %02X", MAPRAM_ADDR(0), MAP_PAGEBITS(0));
   121 	MAP_CLR_PAGEBIT(0, PAGE_BIT_PS0);
   122 	LOG("Clr PS0 = %04X %02X", MAPRAM_ADDR(0), MAP_PAGEBITS(0));
   123 	exit(-1);
   124 #endif
   126 	if (!l7intr) {
   127 		// PS1 is always set on access if no fault
   128 		MAP_SET_PAGEBIT(addr, PAGE_BIT_PS1);
   130 		// Update PS0
   131 		if (ps0_state) {
   132 			MAP_SET_PAGEBIT(addr, PAGE_BIT_PS0);
   133 		} else {
   134 			MAP_CLR_PAGEBIT(addr, PAGE_BIT_PS0);
   135 		}
   136 	}
   138 #ifdef MAPRAM_DEBUG_MESSAGES
   139 	uint16_t new_pagebit2 = MAP_PAGEBITS(addr);
   140 	switch (addr) {
   141 		case 0x000000:
   142 		case 0x001000:
   143 		case 0x002000:
   144 		case 0x003000:
   145 		case 0x004000:
   146 		case 0x033000:
   147 		case 0x034000:
   148 		case 0x035000:
   149 			LOG("Addr %08X %s MapNew %04X Page %04X -- Pagebit update -- ps0 %d, old %s%s => %s%s => %s%s",
   150 					addr,
   151 					write ? "Wr" : "Rd",
   152 					MAPRAM_ADDR(addr),
   153 					MAP_ADDR_TO_PAGE(addr),
   154 					ps0_state,
   155 					old_pagebits & PAGE_BIT_PS0 ? "PS0" : "",
   156 					old_pagebits & PAGE_BIT_PS1 ? "PS1" : "",
   157 					new_pagebit1 & PAGE_BIT_PS0 ? "PS0" : "",
   158 					new_pagebit1 & PAGE_BIT_PS1 ? "PS1" : "",
   159 					new_pagebit2 & PAGE_BIT_PS0 ? "PS0" : "",
   160 					new_pagebit2 & PAGE_BIT_PS1 ? "PS1" : ""
   161 			   );
   162 		default:
   163 			break;
   164 	}
   165 #endif // MAPRAM_DEBUG_MESSAGES
   166 }
   168 bool access_check_dma(void)
   169 {
   170 	// TODO FIXME BUGBUG Sanity check - Make sure DMAC is only accessing RAM addresses
   172 	// DMA access check -- make sure the page is mapped in
   173 	if (!(MAP_PAGEBITS(state.dma_address) & PAGE_BIT_PS0) && !(MAP_PAGEBITS(state.dma_address) & PAGE_BIT_PS1)) {
   174 		// DMA access to page which is not mapped in.
   175 		// Level 7 interrupt, page fault, DMA invoked
   176 		state.genstat = 0xABFF
   177 			| (state.dma_reading ? 0x4000 : 0)
   178 			| (state.pie ? 0x0400 : 0);
   180 		// XXX: Check all this stuff.
   181 		state.bsr0 = 0x3C00;
   182 		state.bsr0 |= (state.dma_address >> 16);
   183 		state.bsr1 = state.dma_address & 0xffff;
   185 		// Update page bits for this transfer
   186 		update_page_bits(state.dma_address, true, !state.dma_reading);
   188 		// XXX: is this right?
   189 		// Fire a Level 7 interrupt
   190 		/*if (state.ee)*/ m68k_set_irq(7);
   192 		LOG("BUS ERROR FROM DMA: genstat=%04X, bsr0=%04X, bsr1=%04X\n", state.genstat, state.bsr0, state.bsr1);
   193 		return false;
   194 	} else {
   195 		// No errors. Just update the page bits.
   196 		update_page_bits(state.dma_address, false, !state.dma_reading);
   197 		return true;
   198 	}
   199 }
   201 /**
   202  * Check memory access permissions for a CPU memory access.
   203  *
   204  * @param	addr	Virtual memory address being accessed (from CPU address bus).
   205  * @param	bits	Word size of this transfer (8, 16 or 32 bits).
   206  * @param	write	<i>true</i> if this is a write operation, <i>false</i> if it is a read operation.
   207  * @return	<i>true</i> if the access was denied and a level-7 interrupt and/or bus error raised.
   208  * 			<i>false</i> if the access was allowed.
   209  */
   210 bool access_check_cpu(uint32_t addr, int bits, bool write)
   211 {
   212 	bool supervisor = (m68k_get_reg(NULL, M68K_REG_SR) & 0x2000);
   213 	bool fault = false;
   215 	// TODO FIXME BUGBUG? Do we need to check for supervisor access here?
   216 	if ((addr >= 0x000000) && (addr <= 0x3FFFFF) && !(MAP_PAGEBITS(addr) & PAGE_BIT_PS1) && !(MAP_PAGEBITS(addr) & PAGE_BIT_PS0)) {
   217 		// (A) Page Fault -- user access to page which is not mapped in
   218 		// Level 7 Interrupt, Bus Error, regs=PAGEFAULT
   219 		if (write) {
   220 			state.genstat = 0x8BFF | (state.pie ? 0x0400 : 0);
   221 		} else {
   222 			state.genstat = 0xCBFF | (state.pie ? 0x0400 : 0);
   223 		}
   224 		fault = true;
   225 	} else if (!supervisor && (addr >= 0x000000) && (addr <= 0x07FFFF)) {
   226 		// (B) User attempted to access the kernel
   227 		// Level 7 Interrupt, Bus Error, regs=KERNEL
   228 		if (write) {
   229 			// XXX: BUGBUG? Is this correct?
   230 			state.genstat = 0x9BFF | (state.pie ? 0x0400 : 0);
   231 		} else {
   232 			state.genstat = 0xDBFF | (state.pie ? 0x0400 : 0);
   233 		}
   234 		fault = true;
   235 	} else if (!supervisor && write && (addr >= 0x000000) && (addr <= 0x3FFFFF) && !(MAP_PAGEBITS(addr) & PAGE_BIT_WE)) {
   236 		// (C) User attempted to write to a page which is not write enabled
   237 		// Level 7 Interrupt, Bus Error, regs=WRITE_EN
   238 		if (write) {
   239 			// XXX: BUGBUG? Is this correct?
   240 			state.genstat = 0x9BFF | (state.pie ? 0x0400 : 0);
   241 		} else {
   242 			state.genstat = 0xDBFF | (state.pie ? 0x0400 : 0);
   243 		}
   244 		fault = true;
   245 	} else if (!supervisor && (addr >= 0x400000) && (addr <= 0xFFFFFF)) {
   246 		// (D) UIE - user I/O exception
   247 		// Bus Error only, regs=UIE
   248 		if (write) {
   249 			state.genstat = 0x9AFF | (state.pie ? 0x0400 : 0);
   250 		} else {
   251 			state.genstat = 0xDAFF | (state.pie ? 0x0400 : 0);
   252 		}
   253 		fault = true;
   254 	}
   256 	unsigned char pagebits_preup = MAP_PAGEBITS(addr & 0x3fffff);
   258 	// Update the page bits first
   259 	update_page_bits(addr, fault, write);
   261 	if (fault) {
   262 		if (bits >= 16)
   263 			state.bsr0 = 0x7C00;
   264 		else
   265 			state.bsr0 = (addr & 1) ? 0x7E00 : 0x7D00;
   266 		// FIXME? Physical or virtual address here?
   267 		state.bsr0 |= (addr >> 16);
   268 		state.bsr1 = addr & 0xffff;
   270 		LOG("CPU Bus Error or L7Intr while %s, vaddr %08X, map %08X, pagebits 0x%02X=>0x%02X bsr0=%04X bsr1=%04X genstat=%04X", 
   271 				write ? "writing" : "reading", addr,
   272 				MAPRAM_ADDR(addr & 0x3fffff),
   273 				pagebits_preup,
   274 				MAP_PAGEBITS(addr & 0x3fffff),
   275 				state.bsr0, state.bsr1, state.genstat);
   277 		// FIXME? BUGBUG? Does EE disable one or both of these?
   278 		// /*if (state.ee)*/ m68k_set_irq(7);
   279 		/*if (state.ee)*/ m68k_pulse_bus_error();
   280 	}
   282 	return fault;
   283 }
   285 // Logging macros
   286 #define LOG_NOT_HANDLED_R(bits)															\
   287 	if (!handled) fprintf(stderr, "unhandled read%02d, addr=0x%08X\n", bits, address);
   289 #define LOG_NOT_HANDLED_W(bits)															\
   290 	if (!handled) fprintf(stderr, "unhandled write%02d, addr=0x%08X, data=0x%08X\n", bits, address, data);
   292 /********************************************************
   293  * I/O read/write functions
   294  ********************************************************/
   296 /**
   297  * Issue a warning if a read operation is made with an invalid size
   298  */
   299 inline static void ENFORCE_SIZE(int bits, uint32_t address, bool read, int allowed, char *regname)
   300 {
   301 	assert((bits == 8) || (bits == 16) || (bits == 32));
   302 	if ((bits & allowed) == 0) {
   303 		LOG("WARNING: %s 0x%08X (%s) with invalid size %d!\n", read ? "read from" : "write to", address, regname, bits);
   304 	}
   305 }
   307 inline static void ENFORCE_SIZE_R(int bits, uint32_t address, int allowed, char *regname)
   308 {
   309 	ENFORCE_SIZE(bits, address, true, allowed, regname);
   310 }
   312 inline static void ENFORCE_SIZE_W(int bits, uint32_t address, int allowed, char *regname)
   313 {
   314 	ENFORCE_SIZE(bits, address, false, allowed, regname);
   315 }
   317 void IoWrite(uint32_t address, uint32_t data, int bits)/*{{{*/
   318 {
   319 	bool handled = false;
   321 	if ((address >= 0x400000) && (address <= 0x7FFFFF)) {
   322 		// I/O register space, zone A
   323 		switch (address & 0x0F0000) {
   324 			case 0x010000:				// General Status Register
   325 				if (bits == 16)
   326 					state.genstat = (data & 0xffff);
   327 				else if (bits == 8) {
   328 					if (address & 0)
   329 						state.genstat = data;
   330 					else
   331 						state.genstat = data << 8;
   332 				}
   333 				handled = true;
   334 				break;
   335 			case 0x030000:				// Bus Status Register 0
   336 				break;
   337 			case 0x040000:				// Bus Status Register 1
   338 				break;
   339 			case 0x050000:				// Phone status
   340 				break;
   341 			case 0x060000:				// DMA Count
   342 				ENFORCE_SIZE_W(bits, address, 16, "DMACOUNT");
   343 				state.dma_count = (data & 0x3FFF);
   344 				state.idmarw = ((data & 0x4000) == 0x4000);
   345 				state.dmaen = ((data & 0x8000) == 0x8000);
   346 				// This handles the "dummy DMA transfer" mentioned in the docs
   347 				// disabled because it causes the floppy test to fail
   348 #if 0
   349 				if (!state.idmarw){
   350 					if (access_check_dma(true)){
   351 						uint32_t newAddr = mapAddr(state.dma_address, true);
   352 						// RAM access
   353 						if (newAddr <= 0x1fffff)
   354 							WR16(state.base_ram, newAddr, state.base_ram_size - 1, 0xFF);
   355 						else if (address <= 0x3FFFFF)
   356 							WR16(state.exp_ram, newAddr - 0x200000, state.exp_ram_size - 1, 0xFF);
   357 					}
   358 				}
   359 #endif
   360 				state.dma_count++;
   361 				handled = true;
   362 				break;
   363 			case 0x070000:				// Line Printer Status Register
   364 				break;
   365 			case 0x080000:				// Real Time Clock
   366 				LOGS("REAL TIME CLOCK WRITE");
   367 				break;
   368 			case 0x090000:				// Phone registers
   369 				switch (address & 0x0FF000) {
   370 					case 0x090000:		// Handset relay
   371 					case 0x098000:
   372 						break;
   373 					case 0x091000:		// Line select 2
   374 					case 0x099000:
   375 						break;
   376 					case 0x092000:		// Hook relay 1
   377 					case 0x09A000:
   378 						break;
   379 					case 0x093000:		// Hook relay 2
   380 					case 0x09B000:
   381 						break;
   382 					case 0x094000:		// Line 1 hold
   383 					case 0x09C000:
   384 						break;
   385 					case 0x095000:		// Line 2 hold
   386 					case 0x09D000:
   387 						break;
   388 					case 0x096000:		// Line 1 A-lead
   389 					case 0x09E000:
   390 						break;
   391 					case 0x097000:		// Line 2 A-lead
   392 					case 0x09F000:
   393 						break;
   394 				}
   395 				break;
   396 			case 0x0A0000:				// Miscellaneous Control Register
   397 				ENFORCE_SIZE_W(bits, address, 16, "MISCCON");
   398 				// TODO: handle the ctrl bits properly
   399 				if (data & 0x8000){
   400 					state.timer_enabled = 1;
   401 				}else{
   402 					state.timer_enabled = 0;
   403 					state.timer_asserted = 0;
   404 				}
   405 				state.dma_reading = (data & 0x4000);
   406 				if (state.leds != ((~data & 0xF00) >> 8)) {
   407 					state.leds = (~data & 0xF00) >> 8;
   408 #ifdef SHOW_LEDS
   409 					printf("LEDs: %s %s %s %s\n",
   410 							(state.leds & 8) ? "R" : "-",
   411 							(state.leds & 4) ? "G" : "-",
   412 							(state.leds & 2) ? "Y" : "-",
   413 							(state.leds & 1) ? "R" : "-");
   414 #endif
   415 				}
   416 				handled = true;
   417 				break;
   418 			case 0x0B0000:				// TM/DIALWR
   419 				break;
   420 			case 0x0C0000:				// Clear Status Register
   421 				state.genstat = 0xFFFF;
   422 				state.bsr0 = 0xFFFF;
   423 				state.bsr1 = 0xFFFF;
   424 				handled = true;
   425 				break;
   426 			case 0x0D0000:				// DMA Address Register
   427 				if (address & 0x004000) {
   428 					// A14 high -- set most significant bits
   429 					state.dma_address = (state.dma_address & 0x1fe) | ((address & 0x3ffe) << 8);
   430 				} else {
   431 					// A14 low -- set least significant bits
   432 					state.dma_address = (state.dma_address & 0x3ffe00) | (address & 0x1fe);
   433 				}
   434 				handled = true;
   435 				break;
   436 			case 0x0E0000:				// Disk Control Register
   437 				{
   438 					bool fd_selected;
   439 					bool hd_selected;
   440 					ENFORCE_SIZE_W(bits, address, 16, "DISKCON");
   441 					// B7 = FDD controller reset
   442 					if ((data & 0x80) == 0) wd2797_reset(&state.fdc_ctx);
   443 					// B6 = drive 0 select
   444 					fd_selected = (data & 0x40) != 0;
   445 					// B5 = motor enable -- TODO
   446 					// B4 = HDD controller reset
   447 					if ((data & 0x10) == 0) wd2010_reset(&state.hdc_ctx);
   448 					// B3 = HDD0 select
   449 					hd_selected = (data & 0x08) != 0;
   450 					// B2,1,0 = HDD0 head select -- TODO?
   451 					if (hd_selected && !state.hd_selected){
   452 						state.fd_selected = false;
   453 						state.hd_selected = true;
   454 					}else if (fd_selected && !state.fd_selected){
   455 						state.hd_selected = false;
   456 						state.fd_selected = true;
   457 					}
   458 					handled = true;
   459 					break;
   460 				}
   461 			case 0x0F0000:				// Line Printer Data Register
   462 				break;
   463 		}
   464 	} else if ((address >= 0xC00000) && (address <= 0xFFFFFF)) {
   465 		// I/O register space, zone B
   466 		switch (address & 0xF00000) {
   467 			case 0xC00000:				// Expansion slots
   468 			case 0xD00000:
   469 				switch (address & 0xFC0000) {
   470 					case 0xC00000:		// Expansion slot 0
   471 					case 0xC40000:		// Expansion slot 1
   472 					case 0xC80000:		// Expansion slot 2
   473 					case 0xCC0000:		// Expansion slot 3
   474 					case 0xD00000:		// Expansion slot 4
   475 					case 0xD40000:		// Expansion slot 5
   476 					case 0xD80000:		// Expansion slot 6
   477 					case 0xDC0000:		// Expansion slot 7
   478 						fprintf(stderr, "NOTE: WR%d to expansion card space, addr=0x%08X, data=0x%08X\n", bits, address, data);
   479 						handled = true;
   480 						break;
   481 				}
   482 				break;
   483 			case 0xE00000:				// HDC, FDC, MCR2 and RTC data bits
   484 			case 0xF00000:
   485 				switch (address & 0x070000) {
   486 					case 0x000000:		// [ef][08]xxxx ==> WD2010 hard disc controller
   487 						wd2010_write_reg(&state.hdc_ctx, (address >> 1) & 7, data);
   488 						handled = true;
   489 						break;
   490 					case 0x010000:		// [ef][19]xxxx ==> WD2797 floppy disc controller
   491 						/*ENFORCE_SIZE_W(bits, address, 16, "FDC REGISTERS");*/
   492 						wd2797_write_reg(&state.fdc_ctx, (address >> 1) & 3, data);
   493 						handled = true;
   494 						break;
   495 					case 0x020000:		// [ef][2a]xxxx ==> Miscellaneous Control Register 2
   496 						// MCR2 - UNIX PC Rev. P5.1 HDD head select b3 and potential HDD#2 select
   497 						wd2010_write_reg(&state.hdc_ctx, UNIXPC_REG_MCR2, data);
   498 						handled = true;
   499 						break;
   500 					case 0x030000:		// [ef][3b]xxxx ==> Real Time Clock data bits
   501 						LOGS("REAL TIME CLOCK DATA WRITE");
   502 						break;
   503 					case 0x040000:		// [ef][4c]xxxx ==> General Control Register
   504 						switch (address & 0x077000) {
   505 							case 0x040000:		// [ef][4c][08]xxx ==> EE
   506 								// Error Enable. If =0, Level7 intrs and bus errors are masked.
   507 								ENFORCE_SIZE_W(bits, address, 16, "EE");
   508 								state.ee = ((data & 0x8000) == 0x8000);
   509 								handled = true;
   510 								break;
   511 							case 0x041000:		// [ef][4c][19]xxx ==> PIE
   512 								ENFORCE_SIZE_W(bits, address, 16, "PIE");
   513 								state.pie = ((data & 0x8000) == 0x8000);
   514 								handled = true;
   515 								break;
   516 							case 0x042000:		// [ef][4c][2A]xxx ==> BP
   517 								break;
   518 							case 0x043000:		// [ef][4c][3B]xxx ==> ROMLMAP
   519 								ENFORCE_SIZE_W(bits, address, 16, "ROMLMAP");
   520 								state.romlmap = ((data & 0x8000) == 0x8000);
   521 								handled = true;
   522 								break;
   523 							case 0x044000:		// [ef][4c][4C]xxx ==> L1 MODEM
   524 								ENFORCE_SIZE_W(bits, address, 16, "L1 MODEM");
   525 								break;
   526 							case 0x045000:		// [ef][4c][5D]xxx ==> L2 MODEM
   527 								ENFORCE_SIZE_W(bits, address, 16, "L2 MODEM");
   528 								break;
   529 							case 0x046000:		// [ef][4c][6E]xxx ==> D/N CONNECT
   530 								ENFORCE_SIZE_W(bits, address, 16, "D/N CONNECT");
   531 								break;
   532 							case 0x047000:		// [ef][4c][7F]xxx ==> Whole screen reverse video
   533 								ENFORCE_SIZE_W(bits, address, 16, "WHOLE SCREEN REVERSE VIDEO");
   534 								break;
   535 						}
   536 					case 0x050000:		// [ef][5d]xxxx ==> 8274
   537 						break;
   538 					case 0x060000:		// [ef][6e]xxxx ==> Control regs
   539 						switch (address & 0x07F000) {
   540 							default:
   541 								break;
   542 						}
   543 						break;
   544 					case 0x070000:		// [ef][7f]xxxx ==> 6850 Keyboard Controller
   545 						// TODO: figure out which sizes are valid (probably just 8 and 16)
   546 						// ENFORCE_SIZE_W(bits, address, 16, "KEYBOARD CONTROLLER");
   547 						if (bits == 8) {
   548 #ifdef LOG_KEYBOARD_WRITES
   549 							LOG("KBD WR %02X => %02X\n", (address >> 1) & 3, data);
   550 #endif
   551 							keyboard_write(&state.kbd, (address >> 1) & 3, data);
   552 							handled = true;
   553 						} else if (bits == 16) {
   554 #ifdef LOG_KEYBOARD_WRITES
   555 							LOG("KBD WR %02X => %04X\n", (address >> 1) & 3, data);
   556 #endif
   557 							keyboard_write(&state.kbd, (address >> 1) & 3, data >> 8);
   558 							handled = true;
   559 						}
   560 						break;
   561 				}
   562 		}
   563 	}
   565 	LOG_NOT_HANDLED_W(bits);
   566 }/*}}}*/
   568 uint32_t IoRead(uint32_t address, int bits)/*{{{*/
   569 {
   570 	bool handled = false;
   571 	uint32_t data = EMPTY & 0xFFFFFFFF;
   573 	if ((address >= 0x400000) && (address <= 0x7FFFFF)) {
   574 		// I/O register space, zone A
   575 		switch (address & 0x0F0000) {
   576 			case 0x010000:				// General Status Register
   577 				/* ENFORCE_SIZE_R(bits, address, 16, "GENSTAT"); */
   578 				if (bits == 32) {
   579 					return ((uint32_t)state.genstat << 16) + (uint32_t)state.genstat;
   580 				} else if (bits == 16) {
   581 					return (uint16_t)state.genstat;
   582 				} else {
   583 					return (uint8_t)(state.genstat & 0xff);
   584 				}
   585 				break;
   586 			case 0x030000:				// Bus Status Register 0
   587 				ENFORCE_SIZE_R(bits, address, 16, "BSR0");
   588 				return ((uint32_t)state.bsr0 << 16) + (uint32_t)state.bsr0;
   589 				break;
   590 			case 0x040000:				// Bus Status Register 1
   591 				ENFORCE_SIZE_R(bits, address, 16, "BSR1");
   592 				return ((uint32_t)state.bsr1 << 16) + (uint32_t)state.bsr1;
   593 				break;
   594 			case 0x050000:				// Phone status
   595 				ENFORCE_SIZE_R(bits, address, 8 | 16, "PHONE STATUS");
   596 				break;
   597 			case 0x060000:				// DMA Count
   598 				// TODO: U/OERR- is always inactive (bit set)... or should it be = DMAEN+?
   599 				// Bit 14 is always unused, so leave it set
   600 				ENFORCE_SIZE_R(bits, address, 16, "DMACOUNT");
   601 				return (state.dma_count & 0x3fff) | 0xC000;
   602 				break;
   603 			case 0x070000:				// Line Printer Status Register
   604 				data = 0x00120012;	// no parity error, no line printer error, no irqs from FDD or HDD
   605 				data |= wd2797_get_irq(&state.fdc_ctx) ? 0x00080008 : 0;
   606 				data |= wd2010_get_irq(&state.hdc_ctx) ? 0x00040004 : 0;
   607 				return data;
   608 				break;
   609 			case 0x080000:				// Real Time Clock
   610 				LOGS("REAL TIME CLOCK READ");
   611 				break;
   612 			case 0x090000:				// Phone registers
   613 				switch (address & 0x0FF000) {
   614 					case 0x090000:		// Handset relay
   615 					case 0x098000:
   616 						break;
   617 					case 0x091000:		// Line select 2
   618 					case 0x099000:
   619 						break;
   620 					case 0x092000:		// Hook relay 1
   621 					case 0x09A000:
   622 						break;
   623 					case 0x093000:		// Hook relay 2
   624 					case 0x09B000:
   625 						break;
   626 					case 0x094000:		// Line 1 hold
   627 					case 0x09C000:
   628 						break;
   629 					case 0x095000:		// Line 2 hold
   630 					case 0x09D000:
   631 						break;
   632 					case 0x096000:		// Line 1 A-lead
   633 					case 0x09E000:
   634 						break;
   635 					case 0x097000:		// Line 2 A-lead
   636 					case 0x09F000:
   637 						break;
   638 				}
   639 				break;
   640 			case 0x0A0000:				// Miscellaneous Control Register -- write only!
   641 				handled = true;
   642 				break;
   643 			case 0x0B0000:				// TM/DIALWR
   644 				break;
   645 			case 0x0C0000:				// Clear Status Register -- write only!
   646 				handled = true;
   647 				break;
   648 			case 0x0D0000:				// DMA Address Register
   649 				break;
   650 			case 0x0E0000:				// Disk Control Register
   651 				break;
   652 			case 0x0F0000:				// Line Printer Data Register
   653 				break;
   654 		}
   655 	} else if ((address >= 0xC00000) && (address <= 0xFFFFFF)) {
   656 		// I/O register space, zone B
   657 		switch (address & 0xF00000) {
   658 			case 0xC00000:				// Expansion slots
   659 			case 0xD00000:
   660 				switch (address & 0xFC0000) {
   661 					case 0xC00000:		// Expansion slot 0
   662 					case 0xC40000:		// Expansion slot 1
   663 					case 0xC80000:		// Expansion slot 2
   664 					case 0xCC0000:		// Expansion slot 3
   665 					case 0xD00000:		// Expansion slot 4
   666 					case 0xD40000:		// Expansion slot 5
   667 					case 0xD80000:		// Expansion slot 6
   668 					case 0xDC0000:		// Expansion slot 7
   669 						fprintf(stderr, "NOTE: RD%d from expansion card space, addr=0x%08X\n", bits, address);
   670 						handled = true;
   671 						break;
   672 				}
   673 				break;
   674 			case 0xE00000:				// HDC, FDC, MCR2 and RTC data bits
   675 			case 0xF00000:
   676 				switch (address & 0x070000) {
   677 					case 0x000000:		// [ef][08]xxxx ==> WD1010 hard disc controller
   678 						return (wd2010_read_reg(&state.hdc_ctx, (address >> 1) & 7));
   680 						break;
   681 					case 0x010000:		// [ef][19]xxxx ==> WD2797 floppy disc controller
   682 						/*ENFORCE_SIZE_R(bits, address, 16, "FDC REGISTERS");*/
   683 						return wd2797_read_reg(&state.fdc_ctx, (address >> 1) & 3);
   684 						break;
   685 					case 0x020000:		// [ef][2a]xxxx ==> Miscellaneous Control Register 2
   686 						break;
   687 					case 0x030000:		// [ef][3b]xxxx ==> Real Time Clock data bits
   688 						LOGS("REAL TIME CLOCK DATA READ");
   689 						break;
   690 					case 0x040000:		// [ef][4c]xxxx ==> General Control Register
   691 						switch (address & 0x077000) {
   692 							case 0x040000:		// [ef][4c][08]xxx ==> EE
   693 							case 0x041000:		// [ef][4c][19]xxx ==> PIE
   694 							case 0x042000:		// [ef][4c][2A]xxx ==> BP
   695 							case 0x043000:		// [ef][4c][3B]xxx ==> ROMLMAP
   696 							case 0x044000:		// [ef][4c][4C]xxx ==> L1 MODEM
   697 							case 0x045000:		// [ef][4c][5D]xxx ==> L2 MODEM
   698 							case 0x046000:		// [ef][4c][6E]xxx ==> D/N CONNECT
   699 								// All write-only registers... TODO: bus error?
   700 								handled = true;
   701 								break;
   702 							case 0x047000:		// [ef][4c][7F]xxx ==> Whole screen reverse video [FIXME: not in TRM]
   703 								break;
   704 						}
   705 						break;
   706 					case 0x050000:		// [ef][5d]xxxx ==> 8274
   707 						break;
   708 					case 0x060000:		// [ef][6e]xxxx ==> Control regs
   709 						switch (address & 0x07F000) {
   710 							default:
   711 								break;
   712 						}
   713 						break;
   714 					case 0x070000:		// [ef][7f]xxxx ==> 6850 Keyboard Controller
   715 						// TODO: figure out which sizes are valid (probably just 8 and 16)
   716 						//ENFORCE_SIZE_R(bits, address, 16, "KEYBOARD CONTROLLER");
   717 						{
   718 							if (bits == 8) {
   719 								return keyboard_read(&state.kbd, (address >> 1) & 3);
   720 							} else {
   721 								return keyboard_read(&state.kbd, (address >> 1) & 3) << 8;
   722 							}
   723 							return data;
   724 						}
   725 						break;
   726 				}
   727 		}
   728 	}
   730 	LOG_NOT_HANDLED_R(bits);
   732 	return data;
   733 }/*}}}*/
   736 /********************************************************
   737  * m68k memory read/write support functions for Musashi
   738  ********************************************************/
   740 /**
   741  * @brief Read M68K memory, 32-bit
   742  */
   743 uint32_t m68k_read_memory_32(uint32_t address)/*{{{*/
   744 {
   745 	uint32_t data = EMPTY & 0xFFFFFFFF;
   747 	// If ROMLMAP is set, force system to access ROM
   748 	if (!state.romlmap)
   749 		address |= 0x800000;
   751 	// Check access permissions
   752 	ACCESS_CHECK_RD(address, 32);
   754 	if ((address >= 0x800000) && (address <= 0xBFFFFF)) {
   755 		// ROM access
   756 		return RD32(state.rom, address, ROM_SIZE - 1);
   757 	} else if (address <= 0x3fffff) {
   758 		// RAM access
   759 		uint32_t newAddr = MAP_ADDR(address);
   761 		if (newAddr <= 0x1fffff) {
   762 			// Base memory wraps around
   763 			return RD32(state.base_ram, newAddr, state.base_ram_size - 1);
   764 		} else {
   765 			if ((newAddr <= (state.exp_ram_size + 0x200000 - 1)) && (newAddr >= 0x200000))
   766 				return RD32(state.exp_ram, newAddr - 0x200000, state.exp_ram_size - 1);
   767 			else
   768 				return EMPTY & 0xffffffff;
   769 		}
   770 	} else if ((address >= 0x400000) && (address <= 0x7FFFFF)) {
   771 		// I/O register space, zone A
   772 		switch (address & 0x0F0000) {
   773 			case 0x000000:				// Map RAM access
   774 				if (address > 0x4007FF) fprintf(stderr, "NOTE: RD32 from MapRAM mirror, addr=0x%08X\n", address);
   775 				return RD32(state.map, address, 0x7FF);
   776 				break;
   777 			case 0x020000:				// Video RAM
   778 				if (address > 0x427FFF) fprintf(stderr, "NOTE: RD32 from VideoRAM mirror, addr=0x%08X\n", address);
   779 				return RD32(state.vram, address, 0x7FFF);
   780 				break;
   781 			default:
   782 				return IoRead(address, 32);
   783 		}
   784 	} else {
   785 		return IoRead(address, 32);
   786 	}
   788 	return data;
   789 }/*}}}*/
   791 /**
   792  * @brief Read M68K memory, 16-bit
   793  */
   794 uint32_t m68k_read_memory_16(uint32_t address)/*{{{*/
   795 {
   796 	uint16_t data = EMPTY & 0xFFFF;
   798 	// If ROMLMAP is set, force system to access ROM
   799 	if (!state.romlmap)
   800 		address |= 0x800000;
   802 	// Check access permissions
   803 	ACCESS_CHECK_RD(address, 16);
   805 	if ((address >= 0x800000) && (address <= 0xBFFFFF)) {
   806 		// ROM access
   807 		data = RD16(state.rom, address, ROM_SIZE - 1);
   808 	} else if (address <= 0x3fffff) {
   809 		// RAM access
   810 		uint32_t newAddr = MAP_ADDR(address);
   812 		if (newAddr <= 0x1fffff) {
   813 			// Base memory wraps around
   814 			return RD16(state.base_ram, newAddr, state.base_ram_size - 1);
   815 		} else {
   816 			if ((newAddr <= (state.exp_ram_size + 0x200000 - 1)) && (newAddr >= 0x200000))
   817 				return RD16(state.exp_ram, newAddr - 0x200000, state.exp_ram_size - 1);
   818 			else
   819 				return EMPTY & 0xffff;
   820 		}
   821 	} else if ((address >= 0x400000) && (address <= 0x7FFFFF)) {
   822 		// I/O register space, zone A
   823 		switch (address & 0x0F0000) {
   824 			case 0x000000:				// Map RAM access
   825 				if (address > 0x4007FF) fprintf(stderr, "NOTE: RD16 from MapRAM mirror, addr=0x%08X\n", address);
   826 				data = RD16(state.map, address, 0x7FF);
   827 				break;
   828 			case 0x020000:				// Video RAM
   829 				if (address > 0x427FFF) fprintf(stderr, "NOTE: RD16 from VideoRAM mirror, addr=0x%08X\n", address);
   830 				data = RD16(state.vram, address, 0x7FFF);
   831 				break;
   832 			default:
   833 				data = IoRead(address, 16);
   834 		}
   835 	} else {
   836 		data = IoRead(address, 16);
   837 	}
   839 	return data;
   840 }/*}}}*/
   842 /**
   843  * @brief Read M68K memory, 8-bit
   844  */
   845 uint32_t m68k_read_memory_8(uint32_t address)/*{{{*/
   846 {
   847 	uint8_t data = EMPTY & 0xFF;
   849 	// If ROMLMAP is set, force system to access ROM
   850 	if (!state.romlmap)
   851 		address |= 0x800000;
   853 	// Check access permissions
   854 	ACCESS_CHECK_RD(address, 8);
   856 	if ((address >= 0x800000) && (address <= 0xBFFFFF)) {
   857 		// ROM access
   858 		data = RD8(state.rom, address, ROM_SIZE - 1);
   859 	} else if (address <= 0x3fffff) {
   860 		// RAM access
   861 		uint32_t newAddr = MAP_ADDR(address);
   863 		if (newAddr <= 0x1fffff) {
   864 			// Base memory wraps around
   865 			return RD8(state.base_ram, newAddr, state.base_ram_size - 1);
   866 		} else {
   867 			if ((newAddr <= (state.exp_ram_size + 0x200000 - 1)) && (newAddr >= 0x200000))
   868 				return RD8(state.exp_ram, newAddr - 0x200000, state.exp_ram_size - 1);
   869 			else
   870 				return EMPTY & 0xff;
   871 		}
   872 	} else if ((address >= 0x400000) && (address <= 0x7FFFFF)) {
   873 		// I/O register space, zone A
   874 		switch (address & 0x0F0000) {
   875 			case 0x000000:				// Map RAM access
   876 				if (address > 0x4007FF) fprintf(stderr, "NOTE: RD8 from MapRAM mirror, addr=0x%08X\n", address);
   877 				data = RD8(state.map, address, 0x7FF);
   878 				break;
   879 			case 0x020000:				// Video RAM
   880 				if (address > 0x427FFF) fprintf(stderr, "NOTE: RD8 from VideoRAM mirror, addr=0x%08X\n", address);
   881 				data = RD8(state.vram, address, 0x7FFF);
   882 				break;
   883 			default:
   884 				data = IoRead(address, 8);
   885 		}
   886 	} else {
   887 		data = IoRead(address, 8);
   888 	}
   890 	return data;
   891 }/*}}}*/
   893 /**
   894  * @brief Write M68K memory, 32-bit
   895  */
   896 void m68k_write_memory_32(uint32_t address, uint32_t value)/*{{{*/
   897 {
   898 	// If ROMLMAP is set, force system to access ROM
   899 	if (!state.romlmap)
   900 		address |= 0x800000;
   902 	// Check access permissions
   903 	ACCESS_CHECK_WR(address, 32);
   905 	if ((address >= 0x800000) && (address <= 0xBFFFFF)) {
   906 		// ROM access
   907 	} else if (address <= 0x3FFFFF) {
   908 		// RAM access
   909 		uint32_t newAddr = MAP_ADDR(address);
   911 		if (newAddr <= 0x1fffff) {
   912 			if (newAddr < state.base_ram_size) {
   913 				WR32(state.base_ram, newAddr, state.base_ram_size - 1, value);
   914 			}
   915 		} else {
   916 			if ((newAddr - 0x200000) < state.exp_ram_size) {
   917 				WR32(state.exp_ram, newAddr - 0x200000, state.exp_ram_size - 1, value);
   918 			}
   919 		}
   920 	} else if ((address >= 0x400000) && (address <= 0x7FFFFF)) {
   921 		// I/O register space, zone A
   922 		switch (address & 0x0F0000) {
   923 			case 0x000000:				// Map RAM access
   924 				if (address > 0x4007FF) fprintf(stderr, "NOTE: WR32 to MapRAM mirror, addr=0x%08X\n", address);
   925 				WR32(state.map, address, 0x7FF, value);
   926 				break;
   927 			case 0x020000:				// Video RAM
   928 				if (address > 0x427FFF) fprintf(stderr, "NOTE: WR32 to VideoRAM mirror, addr=0x%08X\n", address);
   929 				WR32(state.vram, address, 0x7FFF, value);
   930 				break;
   931 			default:
   932 				IoWrite(address, value, 32);
   933 		}
   934 	} else {
   935 		IoWrite(address, value, 32);
   936 	}
   937 }/*}}}*/
   939 /**
   940  * @brief Write M68K memory, 16-bit
   941  */
   942 void m68k_write_memory_16(uint32_t address, uint32_t value)/*{{{*/
   943 {
   944 	// If ROMLMAP is set, force system to access ROM
   945 	if (!state.romlmap)
   946 		address |= 0x800000;
   948 	// Check access permissions
   949 	ACCESS_CHECK_WR(address, 16);
   951 	if ((address >= 0x800000) && (address <= 0xBFFFFF)) {
   952 		// ROM access
   953 	} else if (address <= 0x3FFFFF) {
   954 		// RAM access
   955 		uint32_t newAddr = MAP_ADDR(address);
   957 		if (newAddr <= 0x1fffff) {
   958 			if (newAddr < state.base_ram_size) {
   959 				WR16(state.base_ram, newAddr, state.base_ram_size - 1, value);
   960 			}
   961 		} else {
   962 			if ((newAddr - 0x200000) < state.exp_ram_size) {
   963 				WR16(state.exp_ram, newAddr - 0x200000, state.exp_ram_size - 1, value);
   964 			}
   965 		}
   966 	} else if ((address >= 0x400000) && (address <= 0x7FFFFF)) {
   967 		// I/O register space, zone A
   968 		switch (address & 0x0F0000) {
   969 			case 0x000000:				// Map RAM access
   970 				if (address > 0x4007FF) fprintf(stderr, "NOTE: WR16 to MapRAM mirror, addr=0x%08X, data=0x%04X\n", address, value);
   971 				WR16(state.map, address, 0x7FF, value);
   972 				break;
   973 			case 0x020000:				// Video RAM
   974 				if (address > 0x427FFF) fprintf(stderr, "NOTE: WR16 to VideoRAM mirror, addr=0x%08X, data=0x%04X\n", address, value);
   975 				WR16(state.vram, address, 0x7FFF, value);
   976 				break;
   977 			default:
   978 				IoWrite(address, value, 16);
   979 		}
   980 	} else {
   981 		IoWrite(address, value, 16);
   982 	}
   983 }/*}}}*/
   985 /**
   986  * @brief Write M68K memory, 8-bit
   987  */
   988 void m68k_write_memory_8(uint32_t address, uint32_t value)/*{{{*/
   989 {
   990 	// If ROMLMAP is set, force system to access ROM
   991 	if (!state.romlmap)
   992 		address |= 0x800000;
   994 	// Check access permissions
   995 	ACCESS_CHECK_WR(address, 8);
   997 	if ((address >= 0x800000) && (address <= 0xBFFFFF)) {
   998 		// ROM access (read only!)
   999 	} else if (address <= 0x3FFFFF) {
  1000 		// RAM access
  1001 		uint32_t newAddr = MAP_ADDR(address);
  1003 		if (newAddr <= 0x1fffff) {
  1004 			if (newAddr < state.base_ram_size) {
  1005 				WR8(state.base_ram, newAddr, state.base_ram_size - 1, value);
  1007 		} else {
  1008 			if ((newAddr - 0x200000) < state.exp_ram_size) {
  1009 				WR8(state.exp_ram, newAddr - 0x200000, state.exp_ram_size - 1, value);
  1012 	} else if ((address >= 0x400000) && (address <= 0x7FFFFF)) {
  1013 		// I/O register space, zone A
  1014 		switch (address & 0x0F0000) {
  1015 			case 0x000000:				// Map RAM access
  1016 				if (address > 0x4007FF) fprintf(stderr, "NOTE: WR8 to MapRAM mirror, addr=0x%08X, data=0x%04X\n", address, value);
  1017 				WR8(state.map, address, 0x7FF, value);
  1018 				break;
  1019 			case 0x020000:				// Video RAM
  1020 				if (address > 0x427FFF) fprintf(stderr, "NOTE: WR8 to VideoRAM mirror, addr=0x%08X, data=0x%04X\n", address, value);
  1021 				WR8(state.vram, address, 0x7FFF, value);
  1022 				break;
  1023 			default:
  1024 				IoWrite(address, value, 8);
  1026 	} else {
  1027 		IoWrite(address, value, 8);
  1029 }/*}}}*/
  1032 // for the disassembler
  1033 uint32_t m68k_read_disassembler_32(uint32_t addr)
  1035 	if (addr < 0x400000) {
  1036 		// XXX FIXME BUGBUG update this to use the new mapper macros!
  1037 		uint16_t page = (addr >> 12) & 0x3FF;
  1038 		uint32_t new_page_addr = MAPRAM(page) & 0x3FF;
  1039 		uint32_t newAddr = (new_page_addr << 12) + (addr & 0xFFF);
  1040 		if (newAddr <= 0x1fffff) {
  1041 			if (newAddr >= state.base_ram_size)
  1042 				return EMPTY;
  1043 			else
  1044 				return RD32(state.base_ram, newAddr, state.base_ram_size - 1);
  1045 		} else {
  1046 			if ((newAddr <= (state.exp_ram_size + 0x200000 - 1)) && (newAddr >= 0x200000))
  1047 				return RD32(state.exp_ram, newAddr - 0x200000, state.exp_ram_size - 1);
  1048 			else
  1049 				return EMPTY;
  1051 	} else {
  1052 		LOG("WARNING: Disassembler RD32 out of range 0x%08X\n", addr);
  1053 		return EMPTY;
  1057 uint32_t m68k_read_disassembler_16(uint32_t addr)
  1059 	if (addr < 0x400000) {
  1060 		uint16_t page = (addr >> 12) & 0x3FF;
  1061 		uint32_t new_page_addr = MAPRAM(page) & 0x3FF;
  1062 		uint32_t newAddr = (new_page_addr << 12) + (addr & 0xFFF);
  1063 		if (newAddr <= 0x1fffff) {
  1064 			if (newAddr >= state.base_ram_size)
  1065 				return EMPTY & 0xffff;
  1066 			else
  1067 				return RD16(state.base_ram, newAddr, state.base_ram_size - 1);
  1068 		} else {
  1069 			if ((newAddr <= (state.exp_ram_size + 0x200000 - 1)) && (newAddr >= 0x200000))
  1070 				return RD16(state.exp_ram, newAddr - 0x200000, state.exp_ram_size - 1);
  1071 			else
  1072 				return EMPTY & 0xffff;
  1074 	} else {
  1075 		LOG("WARNING: Disassembler RD16 out of range 0x%08X\n", addr);
  1076 		return EMPTY & 0xffff;
  1080 uint32_t m68k_read_disassembler_8 (uint32_t addr)
  1082 	if (addr < 0x400000) {
  1083 		uint16_t page = (addr >> 12) & 0x3FF;
  1084 		uint32_t new_page_addr = MAPRAM(page) & 0x3FF;
  1085 		uint32_t newAddr = (new_page_addr << 12) + (addr & 0xFFF);
  1086 		if (newAddr <= 0x1fffff) {
  1087 			if (newAddr >= state.base_ram_size)
  1088 				return EMPTY & 0xff;
  1089 			else
  1090 				return RD8(state.base_ram, newAddr, state.base_ram_size - 1);
  1091 		} else {
  1092 			if ((newAddr <= (state.exp_ram_size + 0x200000 - 1)) && (newAddr >= 0x200000))
  1093 				return RD8(state.exp_ram, newAddr - 0x200000, state.exp_ram_size - 1);
  1094 			else
  1095 				return EMPTY & 0xff;
  1097 	} else {
  1098 		LOG("WARNING: Disassembler RD8 out of range 0x%08X\n", addr);
  1099 		return EMPTY & 0xff;