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Fix byte write behavior on a few gate array regs to pass the VAR test in mcd-verificator
author Michael Pavone <pavone@retrodev.com>
date Wed, 19 Jan 2022 00:08:01 -0800
parents c4d066d798c4
children 88deea42caf0
comparison
equal deleted inserted replaced
2055:c4d066d798c4 2056:27bbfcb7850a
375 { 375 {
376 m68k_context *m68k = vcontext; 376 m68k_context *m68k = vcontext;
377 segacd_context *cd = m68k->system; 377 segacd_context *cd = m68k->system;
378 uint32_t reg = (address & 0x1FF) >> 1; 378 uint32_t reg = (address & 0x1FF) >> 1;
379 uint16_t value16; 379 uint16_t value16;
380 if (address & 1) { 380 switch (address >> 1)
381 value16 = cd->gate_array[reg] & 0xFF00 | value; 381 {
382 } else { 382 case GA_CDC_HOST_DATA:
383 value16 = cd->gate_array[reg] & 0xFF | (value << 8); 383 case GA_CDC_DMA_ADDR:
384 case GA_STOP_WATCH:
385 case GA_COMM_FLAG:
386 case GA_CDD_FADER:
387 //these registers treat all writes as word-wide
388 value16 = value | (value << 8);
389 break;
390 default:
391 if (address & 1) {
392 value16 = cd->gate_array[reg] & 0xFF00 | value;
393 } else {
394 value16 = cd->gate_array[reg] & 0xFF | (value << 8);
395 }
384 } 396 }
385 return sub_gate_write16(address, vcontext, value16); 397 return sub_gate_write16(address, vcontext, value16);
386 } 398 }
387 399
388 static uint8_t can_main_access_prog(segacd_context *cd) 400 static uint8_t can_main_access_prog(segacd_context *cd)
586 m68k_context *m68k = vcontext; 598 m68k_context *m68k = vcontext;
587 genesis_context *gen = m68k->system; 599 genesis_context *gen = m68k->system;
588 segacd_context *cd = gen->expansion; 600 segacd_context *cd = gen->expansion;
589 uint32_t reg = (address & 0x1FF) >> 1; 601 uint32_t reg = (address & 0x1FF) >> 1;
590 uint16_t value16; 602 uint16_t value16;
591 if (address & 1) { 603 switch (reg >> 1)
592 value16 = cd->gate_array[reg] & 0xFF00 | value; 604 {
593 } else { 605 case GA_HINT_VECTOR:
594 value16 = cd->gate_array[reg] & 0xFF | (value << 8); 606 case GA_COMM_FLAG:
607 //writes to these regs are always treated as word wide
608 value16 = value | (value << 8);
609 break;
610 default:
611 if (address & 1) {
612 value16 = cd->gate_array[reg] & 0xFF00 | value;
613 } else {
614 value16 = cd->gate_array[reg] & 0xFF | (value << 8);
615 }
595 } 616 }
596 return main_gate_write16(address, vcontext, value16); 617 return main_gate_write16(address, vcontext, value16);
597 } 618 }
598 619
599 segacd_context *alloc_configure_segacd(system_media *media, uint32_t opts, uint8_t force_region, rom_info *info) 620 segacd_context *alloc_configure_segacd(system_media *media, uint32_t opts, uint8_t force_region, rom_info *info)