// license:BSD-3-Clause // copyright-holders:Jonathan Gevaryahu, Robbbert /****************************************************************************** * * Self Contained zexall 'Z80 instruction exerciser' test driver * Zexall originally written by Frank Cringle for ZX Spectrum * Modularized Spectrum-independent Zexall binary supplied by Blargg * Serial interface binary/preloader at 0x0000-0x00FF written by Kevin 'kevtris' Horton * * * mem map: Ram 0000-FFFF (preloaded with binary) Special calls take place for three ram values (this interface was designed by kevtris): FFFD - 'ack' - shared ram with output device; z80 reads from here and considers the byte at FFFF read if this value incremented FFFE - 'req' - shared ram with output device; z80 writes an incrementing value to FFFE to indicate that there is a byte waiting at FFFF and hence requesting the output device on the other end do something about it, until FFFD is incremented by the output device to acknowledge receipt FFFF - 'data' - shared ram with output device; z80 writes the data to be sent to output device here One i/o port is used: 0001 - bit 0 controls whether interrupt timer is enabled (1) or not (0), this is a holdover from a project of kevtris' and can be ignored. ******************************************************************************/ /* Core includes */ #include "emu.h" #include "cpu/z80/z80.h" #include "zexall.h" class zexall_state : public driver_device { public: zexall_state(const machine_config &mconfig, device_type type, const char *tag) : driver_device(mconfig, type, tag), m_maincpu(*this, "maincpu"), m_main_ram(*this, "main_ram"), m_out_data(0), m_out_req(0), m_out_req_last(0), m_out_ack(0) { } DECLARE_READ8_MEMBER( zexall_output_ack_r ); DECLARE_READ8_MEMBER( zexall_output_req_r ); DECLARE_READ8_MEMBER( zexall_output_data_r ); DECLARE_WRITE8_MEMBER( zexall_output_ack_w ); DECLARE_WRITE8_MEMBER( zexall_output_req_w ); DECLARE_WRITE8_MEMBER( zexall_output_data_w ); DECLARE_DRIVER_INIT(zexall); private: required_device m_maincpu; required_shared_ptr m_main_ram; uint8_t m_out_data; // byte written to 0xFFFF uint8_t m_out_req; // byte written to 0xFFFE uint8_t m_out_req_last; // old value at 0xFFFE before the most recent write uint8_t m_out_ack; // byte written to 0xFFFC virtual void machine_reset() override; std::string terminate_string; }; DRIVER_INIT_MEMBER(zexall_state,zexall) { m_out_ack = 0; m_out_req = 0; m_out_req_last = 0; m_out_data = 0; } void zexall_state::machine_reset() { // rom is self-modifying, so need to refresh it on each run // fill main ram with zexall code memcpy(m_main_ram, zexall_program, 0x228a); } READ8_MEMBER( zexall_state::zexall_output_ack_r ) { // spit out the byte in out_byte if out_req is not equal to out_req_last if (m_out_req != m_out_req_last) { osd_printf_info("%c",m_out_data); if (m_out_data != 10 && m_out_data != 13) terminate_string += m_out_data; else terminate_string = ""; if (terminate_string == "Tests complete") machine().schedule_exit(); m_out_req_last = m_out_req; m_out_ack++; } return m_out_ack; } WRITE8_MEMBER( zexall_state::zexall_output_ack_w ) { m_out_ack = data; } READ8_MEMBER( zexall_state::zexall_output_req_r ) { return m_out_req; } WRITE8_MEMBER( zexall_state::zexall_output_req_w ) { m_out_req_last = m_out_req; m_out_req = data; } READ8_MEMBER( zexall_state::zexall_output_data_r ) { return m_out_data; } WRITE8_MEMBER( zexall_state::zexall_output_data_w ) { m_out_data = data; } /****************************************************************************** Address Maps ******************************************************************************/ static ADDRESS_MAP_START(z80_mem, AS_PROGRAM, 8, zexall_state) ADDRESS_MAP_UNMAP_HIGH AM_RANGE(0x0000, 0xfffc) AM_RAM AM_SHARE("main_ram") AM_RANGE(0xfffd, 0xfffd) AM_READWRITE(zexall_output_ack_r,zexall_output_ack_w) AM_RANGE(0xfffe, 0xfffe) AM_READWRITE(zexall_output_req_r,zexall_output_req_w) AM_RANGE(0xffff, 0xffff) AM_READWRITE(zexall_output_data_r,zexall_output_data_w) ADDRESS_MAP_END static ADDRESS_MAP_START(z80_io, AS_IO, 8, zexall_state) ADDRESS_MAP_UNMAP_HIGH AM_RANGE(0x0001, 0x0001) AM_NOP // really a disable/enable for some sort of interrupt timer on kev's hardware, which is completely irrelevant for the zexall test ADDRESS_MAP_END /****************************************************************************** Input Ports ******************************************************************************/ static INPUT_PORTS_START( zexall ) INPUT_PORTS_END /****************************************************************************** Machine Drivers ******************************************************************************/ static MACHINE_CONFIG_START( zexall ) /* basic machine hardware */ MCFG_CPU_ADD("maincpu", Z80, XTAL_3_579545MHz) MCFG_CPU_PROGRAM_MAP(z80_mem) MCFG_CPU_IO_MAP(z80_io) MACHINE_CONFIG_END /****************************************************************************** ROM Definitions ******************************************************************************/ ROM_START(zexall) ROM_REGION(0x0, "romcode", 0) ROM_END /****************************************************************************** Drivers ******************************************************************************/ /* YEAR NAME PARENT COMPAT MACHINE INPUT INIT COMPANY FULLNAME FLAGS */ COMP( 2009, zexall, 0, 0, zexall, zexall, zexall_state, zexall, "Frank Cringle & MESSDEV", "ZEXALL Z80 instruction set exerciser (modified for MESS)", MACHINE_NO_SOUND_HW )