mirror of
https://github.com/ekeeke/Genesis-Plus-GX.git
synced 2024-12-29 04:31:49 +01:00
28775cc3aa
---------- * added Mega CD / Sega CD hardware emulation (incl. Sub 68K, CDD, CDC, PCM, GFX rotation/scaling, etc) * added .ISO & .BIN CD image file support * added 512K backup cartridge RAM support * added savestate support for CD games NOTES: ~~~~~~ * to play CD games, original BIOS ROM files are required in /genplus/bios/ directory: unzip & rename them to bios_CD_U.bin, bios_CD_E.bin, bios_CD_J.bin * CD audio tracks (CD-DA) are not supported (yet) [Core/CPU] ---------- * modified 68k core for Mega CD / Sega CD support [Core/VDP] --------------- * improved DMA accuracy * added support for 8-bit VRAM writes with undocumented code value (verified on real hardware by Nemesis) [Gamecube/Wii] --------------- * modified Master System & Game Gear "BIOS" support (files should be named bios_U.sms, bios_J.sms, bios_E.sms & bios.gg and copied to /genplus/bios directory). * replaced "Hard Reset" button by a Soft Reset for systems having a Reset button (Mega Drive / Genesis & Master System) * State & SRAM files are now only compressed when saving to Gamecube Memory Cards * various fixes & cleanup. [Core/SCD] ---------- * added Mega CD / Sega CD hardware emulation (incl. Sub 68K, CDD, CDC, PCM, GFX rotation/scaling, etc) * added .ISO & .BIN CD image file support * added 512K backup cartridge RAM support * added savestate support for CD games NOTES: ~~~~~~ * to play CD games, original BIOS ROM files are required in /genplus/bios/ directory: unzip & rename them to bios_CD_U.bin, bios_CD_E.bin, bios_CD_J.bin * CD audio tracks (CD-DA) are not supported (yet) [Core/CPU] ---------- * modified 68k core for Mega CD / Sega CD support [Core/VDP] --------------- * improved DMA accuracy * added support for 8-bit VRAM writes with undocumented code value (verified on real hardware by Nemesis) [Gamecube/Wii] --------------- * modified Master System & Game Gear "BIOS" support (files should be named bios_U.sms, bios_J.sms, bios_E.sms & bios.gg and copied to /genplus/bios directory). * replaced "Hard Reset" button by a Soft Reset for systems having a Reset button (Mega Drive / Genesis & Master System) * State & SRAM files are now only compressed when saving to Gamecube Memory Cards * various fixes & cleanup.
554 lines
17 KiB
C
554 lines
17 KiB
C
/****************************************************************************
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* Genesis Plus
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* I2C Serial EEPROM (24Cxx) support
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*
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* Copyright (C) 2007-2011 Eke-Eke (Genesis Plus GX)
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*
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* Redistribution and use of this code or any derivative works are permitted
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* provided that the following conditions are met:
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*
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* - Redistributions may not be sold, nor may they be used in a commercial
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* product or activity.
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*
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* - Redistributions that are modified from the original source must include the
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* complete source code, including the source code for all components used by a
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* binary built from the modified sources. However, as a special exception, the
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* source code distributed need not include anything that is normally distributed
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* (in either source or binary form) with the major components (compiler, kernel,
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* and so on) of the operating system on which the executable runs, unless that
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* component itself accompanies the executable.
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*
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* - Redistributions must reproduce the above copyright notice, this list of
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* conditions and the following disclaimer in the documentation and/or other
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* materials provided with the distribution.
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*
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
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* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
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* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
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* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
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* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
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* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
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* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
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* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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* POSSIBILITY OF SUCH DAMAGE.
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*
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****************************************************************************************/
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#include "shared.h"
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#include "md_eeprom.h"
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#define GAME_CNT 28
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T_EEPROM_24C md_eeprom;
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typedef struct
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{
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char game_id[16];
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uint16 chk;
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T_EEPROM_TYPE type;
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} T_GAME_ENTRY;
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static const T_GAME_ENTRY database[GAME_CNT] =
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{
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/* ACCLAIM mappers */
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/* 24C02 (old mapper) */
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{{"T-081326" }, 0, {8, 0xFF, 0xFF, 0x200001, 0x200001, 0x200001, 0, 1, 1}}, /* NBA Jam (UE) */
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{{"T-81033" }, 0, {8, 0xFF, 0xFF, 0x200001, 0x200001, 0x200001, 0, 1, 1}}, /* NBA Jam (J) */
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/* 24C02 */
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{{"T-081276" }, 0, {8, 0xFF, 0xFF, 0x200001, 0x200001, 0x200000, 0, 0, 0}}, /* NFL Quarterback Club */
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/* 24C04 */
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{{"T-81406" }, 0, {8, 0x1FF, 0x1FF, 0x200001, 0x200001, 0x200000, 0, 0, 0}}, /* NBA Jam TE */
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/* 24C16 */
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{{"T-081586" }, 0, {8, 0x7FF, 0x7FF, 0x200001, 0x200001, 0x200000, 0, 0, 0}}, /* NFL Quarterback Club '96 */
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/* 24C65 */
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{{"T-81576" }, 0, {16, 0x1FFF, 0x1FFF, 0x200001, 0x200001, 0x200000, 0, 0, 0}}, /* College Slam */
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{{"T-81476" }, 0, {16, 0x1FFF, 0x1FFF, 0x200001, 0x200001, 0x200000, 0, 0, 0}}, /* Frank Thomas Big Hurt Baseball */
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/* EA mapper (24C01 only) */
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{{"T-50176" }, 0, {7, 0x7F, 0x7F, 0x200001, 0x200001, 0x200001, 7, 7, 6}}, /* Rings of Power */
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{{"T-50396" }, 0, {7, 0x7F, 0x7F, 0x200001, 0x200001, 0x200001, 7, 7, 6}}, /* NHLPA Hockey 93 */
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{{"T-50446" }, 0, {7, 0x7F, 0x7F, 0x200001, 0x200001, 0x200001, 7, 7, 6}}, /* John Madden Football 93 */
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{{"T-50516" }, 0, {7, 0x7F, 0x7F, 0x200001, 0x200001, 0x200001, 7, 7, 6}}, /* John Madden Football 93 (Championship Ed.) */
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{{"T-50606" }, 0, {7, 0x7F, 0x7F, 0x200001, 0x200001, 0x200001, 7, 7, 6}}, /* Bill Walsh College Football */
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/* SEGA mapper (24C01 only) */
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{{"T-12046" }, 0xAD23, {7, 0x7F, 0x7F, 0x200001, 0x200001, 0x200001, 0, 0, 1}}, /* Megaman - The Wily Wars */
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{{"T-12053" }, 0xEA80, {7, 0x7F, 0x7F, 0x200001, 0x200001, 0x200001, 0, 0, 1}}, /* Rockman Mega World [Alt] */
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{{"MK-1215" }, 0, {7, 0x7F, 0x7F, 0x200001, 0x200001, 0x200001, 0, 0, 1}}, /* Evander 'Real Deal' Holyfield's Boxing */
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{{"MK-1228" }, 0, {7, 0x7F, 0x7F, 0x200001, 0x200001, 0x200001, 0, 0, 1}}, /* Greatest Heavyweights of the Ring (U) */
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{{"G-5538" }, 0, {7, 0x7F, 0x7F, 0x200001, 0x200001, 0x200001, 0, 0, 1}}, /* Greatest Heavyweights of the Ring (J) */
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{{"PR-1993" }, 0, {7, 0x7F, 0x7F, 0x200001, 0x200001, 0x200001, 0, 0, 1}}, /* Greatest Heavyweights of the Ring (E) */
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{{"G-4060" }, 0, {7, 0x7F, 0x7F, 0x200001, 0x200001, 0x200001, 0, 0, 1}}, /* Wonderboy in Monster World */
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{{"00001211-00"}, 0, {7, 0x7F, 0x7F, 0x200001, 0x200001, 0x200001, 0, 0, 1}}, /* Sports Talk Baseball */
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{{"00004076-00"}, 0, {7, 0x7F, 0x7F, 0x200001, 0x200001, 0x200001, 0, 0, 1}}, /* Honoo no Toukyuuji Dodge Danpei */
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{{"G-4524" }, 0, {7, 0x7F, 0x7F, 0x200001, 0x200001, 0x200001, 0, 0, 1}}, /* Ninja Burai Densetsu */
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{{"00054503-00"}, 0, {7, 0x7F, 0x7F, 0x200001, 0x200001, 0x200001, 0, 0, 1}}, /* Game Toshokan */
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/* CODEMASTERS mapper */
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/* 24C08 */
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{{"T-120106" }, 0, {8, 0x3FF, 0x3FF, 0x300000, 0x380001, 0x300000, 0, 7, 1}}, /* Brian Lara Cricket */
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{{"00000000-00"}, 0xCEE0, {8, 0x3FF, 0x3FF, 0x300000, 0x380001, 0x300000, 0, 7, 1}}, /* Micro Machines Military */
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/* 24C16 */
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{{"T-120096" }, 0, {8, 0x7FF, 0x7FF, 0x300000, 0x380001, 0x300000, 0, 7, 1}}, /* Micro Machines 2 - Turbo Tournament */
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{{"00000000-00"}, 0x2C41, {8, 0x7FF, 0x7FF, 0x300000, 0x380001, 0x300000, 0, 7, 1}}, /* Micro Machines Turbo Tournament 96 */
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/* 24C65 */
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{{"T-120146-50"}, 0, {16, 0x1FFF, 0x1FFF, 0x300000, 0x380001, 0x300000, 0, 7, 1}} /* Brian Lara Cricket 96, Shane Warne Cricket */
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};
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static void eeprom_update(void);
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static unsigned char eeprom_out(void);
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void md_eeprom_init()
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{
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int i = 0;
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/* initialize eeprom */
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memset(&md_eeprom, 0, sizeof(T_EEPROM_24C));
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md_eeprom.sda = md_eeprom.old_sda = 1;
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md_eeprom.scl = md_eeprom.old_scl = 1;
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md_eeprom.state = STAND_BY;
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/* no eeprom by default */
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sram.custom = 0;
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/* look into game database */
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while (i<GAME_CNT)
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{
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if (strstr(rominfo.product,database[i].game_id) != NULL)
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{
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/* additional check (Micro Machines, Rockman Mega World) */
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if ((database[i].chk == 0x0000) || (database[i].chk == rominfo.realchecksum))
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{
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sram.custom = 1;
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sram.on = 1;
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memcpy(&md_eeprom.type, &database[i].type, sizeof(T_EEPROM_TYPE));
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return;
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}
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}
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i++;
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}
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/* Game not found in database but ROM header indicates it uses EEPROM */
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if (sram.detected)
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{
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if ((sram.end - sram.start) < 2)
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{
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/* set SEGA mapper as default */
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sram.custom = 1;
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memcpy(&md_eeprom.type, &database[9].type, sizeof(T_EEPROM_TYPE));
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}
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}
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}
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unsigned int md_eeprom_read_byte(unsigned int address)
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{
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if (address == md_eeprom.type.sda_out_adr)
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{
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return eeprom_out();
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}
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return READ_BYTE(cart.rom, address);
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}
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unsigned int md_eeprom_read_word(unsigned int address)
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{
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if (address == md_eeprom.type.sda_out_adr)
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{
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return (eeprom_out() << 8);
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}
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if (address == (md_eeprom.type.sda_out_adr ^ 1))
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{
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return eeprom_out();
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}
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return *(uint16 *)(cart.rom + address);
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}
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void md_eeprom_write_byte(unsigned int address, unsigned int data)
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{
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int do_update = 0;
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if (address == md_eeprom.type.sda_in_adr)
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{
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md_eeprom.sda = (data >> md_eeprom.type.sda_in_bit) & 1;
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do_update = 1;
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}
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if (address == md_eeprom.type.scl_adr)
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{
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md_eeprom.scl = (data >> md_eeprom.type.scl_bit) & 1;
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do_update = 1;
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}
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if (do_update)
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{
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eeprom_update();
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return;
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}
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m68k_unused_8_w(address, data);
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}
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void md_eeprom_write_word(unsigned int address, unsigned int data)
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{
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int do_update = 0;
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if (address == md_eeprom.type.sda_in_adr)
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{
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md_eeprom.sda = (data >> (8 + md_eeprom.type.sda_in_bit)) & 1;
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do_update = 1;
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}
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else if (address == (md_eeprom.type.sda_in_adr ^1))
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{
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md_eeprom.sda = (data >> md_eeprom.type.sda_in_bit) & 1;
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do_update = 1;
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}
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if (address == md_eeprom.type.scl_adr)
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{
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md_eeprom.scl = (data >> (8 + md_eeprom.type.scl_bit)) & 1;
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do_update = 1;
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}
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else if (address == (md_eeprom.type.scl_adr ^1))
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{
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md_eeprom.scl = (data >> md_eeprom.type.scl_bit) & 1;
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do_update = 1;
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}
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if (do_update)
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{
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eeprom_update();
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return;
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}
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m68k_unused_16_w(address, data);
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}
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INLINE void Detect_START()
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{
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if (md_eeprom.old_scl && md_eeprom.scl)
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{
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if (md_eeprom.old_sda && !md_eeprom.sda)
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{
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md_eeprom.cycles = 0;
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md_eeprom.slave_mask = 0;
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if (md_eeprom.type.address_bits == 7)
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{
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md_eeprom.word_address = 0;
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md_eeprom.state = GET_WORD_ADR_7BITS;
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}
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else md_eeprom.state = GET_SLAVE_ADR;
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}
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}
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}
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INLINE void Detect_STOP()
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{
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if (md_eeprom.old_scl && md_eeprom.scl)
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{
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if (!md_eeprom.old_sda && md_eeprom.sda)
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{
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md_eeprom.state = STAND_BY;
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}
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}
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}
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static void eeprom_update(void)
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{
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/* EEPROM current state */
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switch (md_eeprom.state)
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{
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/* Standby Mode */
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case STAND_BY:
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{
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Detect_START();
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Detect_STOP();
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break;
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}
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/* Suspended Mode */
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case WAIT_STOP:
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{
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Detect_STOP();
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break;
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}
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/* Get Word Address 7 bits: MODE-1 only (24C01)
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* and R/W bit
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*/
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case GET_WORD_ADR_7BITS:
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{
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Detect_START();
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Detect_STOP();
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/* look for SCL LOW to HIGH transition */
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if (!md_eeprom.old_scl && md_eeprom.scl)
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{
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if (md_eeprom.cycles == 0) md_eeprom.cycles ++;
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}
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/* look for SCL HIGH to LOW transition */
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if (md_eeprom.old_scl && !md_eeprom.scl && (md_eeprom.cycles > 0))
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{
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if (md_eeprom.cycles < 8)
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{
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md_eeprom.word_address |= (md_eeprom.old_sda << (7 - md_eeprom.cycles));
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}
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else if (md_eeprom.cycles == 8)
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{
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md_eeprom.rw = md_eeprom.old_sda;
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}
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else
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{ /* ACK CYCLE */
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md_eeprom.cycles = 0;
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md_eeprom.word_address &= md_eeprom.type.size_mask;
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md_eeprom.state = md_eeprom.rw ? READ_DATA : WRITE_DATA;
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}
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md_eeprom.cycles ++;
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}
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break;
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}
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/* Get Slave Address (3bits) : MODE-2 & MODE-3 only (24C01 - 24C512) (0-3bits, depending on the array size)
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* or/and Word Address MSB: MODE-2 only (24C04 - 24C16) (0-3bits, depending on the array size)
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* and R/W bit
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*/
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case GET_SLAVE_ADR:
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{
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Detect_START();
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Detect_STOP();
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/* look for SCL LOW to HIGH transition */
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if (!md_eeprom.old_scl && md_eeprom.scl)
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{
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if (md_eeprom.cycles == 0) md_eeprom.cycles ++;
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}
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/* look for SCL HIGH to LOW transition */
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if (md_eeprom.old_scl && !md_eeprom.scl && (md_eeprom.cycles > 0))
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{
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if ((md_eeprom.cycles > 4) && (md_eeprom.cycles <8))
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{
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if ((md_eeprom.type.address_bits == 16) ||
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(md_eeprom.type.size_mask < (1 << (15 - md_eeprom.cycles))))
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{
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/* this is a SLAVE ADDRESS bit */
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md_eeprom.slave_mask |= (md_eeprom.old_sda << (7 - md_eeprom.cycles));
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}
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else
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{
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/* this is a WORD ADDRESS high bit */
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if (md_eeprom.old_sda) md_eeprom.word_address |= (1 << (15 - md_eeprom.cycles));
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else md_eeprom.word_address &= ~(1 << (15 - md_eeprom.cycles));
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}
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}
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else if (md_eeprom.cycles == 8) md_eeprom.rw = md_eeprom.old_sda;
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else if (md_eeprom.cycles > 8)
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{
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/* ACK CYCLE */
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md_eeprom.cycles = 0;
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if (md_eeprom.type.address_bits == 16)
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{
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/* two ADDRESS bytes */
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md_eeprom.state = md_eeprom.rw ? READ_DATA : GET_WORD_ADR_HIGH;
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md_eeprom.slave_mask <<= 16;
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}
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else
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{
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/* one ADDRESS byte */
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md_eeprom.state = md_eeprom.rw ? READ_DATA : GET_WORD_ADR_LOW;
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md_eeprom.slave_mask <<= 8;
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}
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}
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md_eeprom.cycles ++;
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}
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break;
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}
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/* Get Word Address MSB (4-8bits depending on the array size)
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* MODE-3 only (24C32 - 24C512)
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*/
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case GET_WORD_ADR_HIGH:
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{
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Detect_START();
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Detect_STOP();
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/* look for SCL HIGH to LOW transition */
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if (md_eeprom.old_scl && !md_eeprom.scl)
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{
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if (md_eeprom.cycles < 9)
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{
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if ((md_eeprom.type.size_mask + 1) < (1 << (17 - md_eeprom.cycles)))
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{
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/* ignored bit: slave mask should be right-shifted by one */
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md_eeprom.slave_mask >>= 1;
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}
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else
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{
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/* this is a WORD ADDRESS high bit */
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if (md_eeprom.old_sda) md_eeprom.word_address |= (1 << (16 - md_eeprom.cycles));
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else md_eeprom.word_address &= ~(1 << (16 - md_eeprom.cycles));
|
|
}
|
|
|
|
md_eeprom.cycles ++;
|
|
}
|
|
else
|
|
{
|
|
/* ACK CYCLE */
|
|
md_eeprom.cycles = 1;
|
|
md_eeprom.state = GET_WORD_ADR_LOW;
|
|
}
|
|
}
|
|
break;
|
|
}
|
|
|
|
/* Get Word Address LSB: 7bits (24C01) or 8bits (24C02-24C512)
|
|
* MODE-2 and MODE-3 only (24C01 - 24C512)
|
|
*/
|
|
case GET_WORD_ADR_LOW:
|
|
{
|
|
Detect_START();
|
|
Detect_STOP();
|
|
|
|
/* look for SCL HIGH to LOW transition */
|
|
if (md_eeprom.old_scl && !md_eeprom.scl)
|
|
{
|
|
if (md_eeprom.cycles < 9)
|
|
{
|
|
if ((md_eeprom.type.size_mask + 1) < (1 << (9 - md_eeprom.cycles)))
|
|
{
|
|
/* ignored bit (X24C01): slave mask should be right-shifted by one */
|
|
md_eeprom.slave_mask >>= 1;
|
|
}
|
|
else
|
|
{
|
|
/* this is a WORD ADDRESS high bit */
|
|
if (md_eeprom.old_sda) md_eeprom.word_address |= (1 << (8 - md_eeprom.cycles));
|
|
else md_eeprom.word_address &= ~(1 << (8 - md_eeprom.cycles));
|
|
}
|
|
|
|
md_eeprom.cycles ++;
|
|
}
|
|
else
|
|
{
|
|
/* ACK CYCLE */
|
|
md_eeprom.cycles = 1;
|
|
md_eeprom.word_address &= md_eeprom.type.size_mask;
|
|
md_eeprom.state = WRITE_DATA;
|
|
}
|
|
}
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* Read Cycle
|
|
*/
|
|
case READ_DATA:
|
|
{
|
|
Detect_START();
|
|
Detect_STOP();
|
|
|
|
/* look for SCL HIGH to LOW transition */
|
|
if (md_eeprom.old_scl && !md_eeprom.scl)
|
|
{
|
|
if (md_eeprom.cycles < 9) md_eeprom.cycles ++;
|
|
else
|
|
{
|
|
md_eeprom.cycles = 1;
|
|
|
|
/* ACK not received */
|
|
if (md_eeprom.old_sda) md_eeprom.state = WAIT_STOP;
|
|
}
|
|
}
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* Write Cycle
|
|
*/
|
|
case WRITE_DATA:
|
|
{
|
|
Detect_START();
|
|
Detect_STOP();
|
|
|
|
/* look for SCL HIGH to LOW transition */
|
|
if (md_eeprom.old_scl && !md_eeprom.scl)
|
|
{
|
|
if (md_eeprom.cycles < 9)
|
|
{
|
|
/* Write DATA bits (max 64kBytes) */
|
|
uint16 sram_address = (md_eeprom.slave_mask | md_eeprom.word_address) & 0xFFFF;
|
|
if (md_eeprom.old_sda) sram.sram[sram_address] |= (1 << (8 - md_eeprom.cycles));
|
|
else sram.sram[sram_address] &= ~(1 << (8 - md_eeprom.cycles));
|
|
|
|
if (md_eeprom.cycles == 8)
|
|
{
|
|
/* WORD ADDRESS is incremented (roll up at maximum pagesize) */
|
|
md_eeprom.word_address = (md_eeprom.word_address & (0xFFFF - md_eeprom.type.pagewrite_mask)) |
|
|
((md_eeprom.word_address + 1) & md_eeprom.type.pagewrite_mask);
|
|
}
|
|
|
|
md_eeprom.cycles ++;
|
|
}
|
|
else md_eeprom.cycles = 1; /* ACK cycle */
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
|
|
md_eeprom.old_scl = md_eeprom.scl;
|
|
md_eeprom.old_sda = md_eeprom.sda;
|
|
}
|
|
|
|
static unsigned char eeprom_out(void)
|
|
{
|
|
uint8 sda_out = md_eeprom.sda;
|
|
|
|
/* EEPROM state */
|
|
switch (md_eeprom.state)
|
|
{
|
|
case READ_DATA:
|
|
{
|
|
if (md_eeprom.cycles < 9)
|
|
{
|
|
/* Return DATA bits (max 64kBytes) */
|
|
uint16 sram_address = (md_eeprom.slave_mask | md_eeprom.word_address) & 0xffff;
|
|
sda_out = (sram.sram[sram_address] >> (8 - md_eeprom.cycles)) & 1;
|
|
|
|
if (md_eeprom.cycles == 8)
|
|
{
|
|
/* WORD ADDRESS is incremented (roll up at maximum array size) */
|
|
md_eeprom.word_address ++;
|
|
md_eeprom.word_address &= md_eeprom.type.size_mask;
|
|
}
|
|
}
|
|
break;
|
|
}
|
|
|
|
case GET_WORD_ADR_7BITS:
|
|
case GET_SLAVE_ADR:
|
|
case GET_WORD_ADR_HIGH:
|
|
case GET_WORD_ADR_LOW:
|
|
case WRITE_DATA:
|
|
{
|
|
if (md_eeprom.cycles == 9) sda_out = 0;
|
|
break;
|
|
}
|
|
|
|
default:
|
|
{
|
|
break;
|
|
}
|
|
}
|
|
|
|
return (sda_out << md_eeprom.type.sda_out_bit);
|
|
}
|