/* * libtilemcore - Graphing calculator emulation library * * Copyright (C) 2001 Solignac Julien * Copyright (C) 2004-2011 Benjamin Moody * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public License * as published by the Free Software Foundation; either version 2.1 of * the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, see * . */ #ifdef HAVE_CONFIG_H # include #endif #include #include #include "xs.h" /* FIXME: what effect, if any, do ports 27 and 28 have in memory mapping mode 1? */ void xs_z80_wrmem(TilemCalc* calc, dword A, byte v) { unsigned long pa; byte page; page = calc->mempagemap[A>>14]; if (A & 0x8000) { if (A > (0xFFFF - 64 * calc->hwregs[PORT27])) page = 0x80; else if (A < (0x8000 + 64 * calc->hwregs[PORT28])) page = 0x81; } pa = (A & 0x3FFF) + 0x4000L*page; if (pa<0x200000) { calc->z80.clock += calc->hwregs[FLASH_WRITE_DELAY]; tilem_flash_write_byte(calc, pa, v); } else if (pa < 0x220000) { calc->z80.clock += calc->hwregs[RAM_WRITE_DELAY]; *(calc->mem+pa) = v; } } static inline byte readbyte(TilemCalc* calc, dword pa) { static const byte protectbytes[6] = {0x00,0x00,0xed,0x56,0xf3,0xd3}; int state = calc->hwregs[PROTECTSTATE]; byte value; if (pa < 0x200000 && (calc->flash.state || calc->flash.busy)) value = tilem_flash_read_byte(calc, pa); else value = *(calc->mem + pa); if (pa < 0x1F0000 || pa >= 0x200000) calc->hwregs[PROTECTSTATE] = 0; else if (state == 6) calc->hwregs[PROTECTSTATE] = 7; else if (state < 6 && value == protectbytes[state]) calc->hwregs[PROTECTSTATE] = state + 1; else calc->hwregs[PROTECTSTATE] = 0; return (value); } byte xs_z80_rdmem(TilemCalc* calc, dword A) { byte page; unsigned long pa; byte value; page = calc->mempagemap[A>>14]; if (A & 0x8000) { if (A > (0xFFFF - 64 * calc->hwregs[PORT27])) page = 0x80; else if (A < (0x8000 + 64 * calc->hwregs[PORT28])) page = 0x81; } if (TILEM_UNLIKELY(page == 0x7E && !calc->flash.unlock)) { tilem_warning(calc, "Reading from read-protected sector"); return (0xff); } pa = (A & 0x3FFF) + 0x4000L*page; if (pa < 0x200000) calc->z80.clock += calc->hwregs[FLASH_READ_DELAY]; else calc->z80.clock += calc->hwregs[RAM_READ_DELAY]; value = readbyte(calc, pa); return (value); } byte xs_z80_rdmem_m1(TilemCalc* calc, dword A) { byte page; unsigned long pa, m; byte value; page = calc->mempagemap[A>>14]; if (A & 0x8000) { if (A > (0xFFFF - 64 * calc->hwregs[PORT27])) page = 0x80; else if (A < (0x8000 + 64 * calc->hwregs[PORT28])) page = 0x81; } if (TILEM_UNLIKELY(page == 0x7E && !calc->flash.unlock)) { tilem_warning(calc, "Reading from read-protected sector"); return (0xff); } pa = (A & 0x3FFF) + 0x4000L*page; if (pa < 0x200000) { calc->z80.clock += calc->hwregs[FLASH_EXEC_DELAY]; if (TILEM_UNLIKELY(page >= calc->hwregs[PORT22] && page <= calc->hwregs[PORT23])) { tilem_warning(calc, "Executing in restricted Flash area"); tilem_z80_exception(calc, TILEM_EXC_FLASH_EXEC); } } else { calc->z80.clock += calc->hwregs[RAM_EXEC_DELAY]; /* Note: this isn't quite strict enough; when port 21 is set to 30h, the "ghost" RAM pages 88-8F are treated as distinct pages for restriction purposes. This detail probably isn't worth emulating. */ m = pa & calc->hwregs[NO_EXEC_RAM_MASK]; if (TILEM_UNLIKELY(m < calc->hwregs[NO_EXEC_RAM_LOWER] || m > calc->hwregs[NO_EXEC_RAM_UPPER])) { tilem_warning(calc, "Executing in restricted RAM area"); tilem_z80_exception(calc, TILEM_EXC_RAM_EXEC); } } value = readbyte(calc, pa); if (TILEM_UNLIKELY(value == 0xff && A == 0x0038)) { tilem_warning(calc, "No OS installed"); tilem_z80_exception(calc, TILEM_EXC_FLASH_EXEC); } return (value); } dword xs_mem_ltop(TilemCalc* calc, dword A) { byte page = calc->mempagemap[A >> 14]; if (A & 0x8000) { if (A > (0xFFFF - 64 * calc->hwregs[PORT27])) page = 0x80; else if (A < (0x8000 + 64 * calc->hwregs[PORT28])) page = 0x81; } return ((page << 14) | (A & 0x3fff)); } dword xs_mem_ptol(TilemCalc* calc, dword A) { byte page = A >> 14; if (!page) return (A & 0x3fff); if (page == calc->mempagemap[1]) return (0x4000 | (A & 0x3fff)); if ((A & 0x3fff) < 64 * calc->hwregs[PORT28]) { if (page == 0x81) return (0x8000 | (A & 0x3fff)); } else { if (page == calc->mempagemap[2]) return (0x8000 | (A & 0x3fff)); } if ((A & 0x3fff) >= (0x4000 - 64 * calc->hwregs[PORT27])) { if (page == 0x80) return (0xC000 | (A & 0x3fff)); } else { if (page == calc->mempagemap[3]) return (0xC000 | (A & 0x3fff)); } return (0xffffffff); }