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Exception at EIP=000000000200aec8 (sun_keyboard_port_device::write_txd(int)+0x0008): ACCESS VIOLATION
While attempting to read memory at 0000000000000638
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RAX=000000000925ab78 RBX=0000000000000001 RCX=0000000000000000 RDX=0000000000000001
RSI=000000000c43cae0 RDI=0000000016fd7120 RBP=0000000000228180 RSP=0000000000228160
 R8=0000000000000000 R9=0000000000000001 R10=0000000000000000 R11=0000000000000000
R12=000000000c43d328 R13=00000000ffffffff R14=0000000000000003 R15=0000000008cfc860
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Stack crawl:
  0000000000228160: 000000000200aec8 (sun_keyboard_port_device::write_txd(int)+0x0008)
  00000000002281b0: 0000000001fc4f14 (sun_keyboard_adaptor_device::input_txd(int)+0x0014)
  00000000002281e0: 0000000001fc2dea (rs232_port_device::write_txd(int)+0x001a)
  0000000000228220: 000000000315a239 (devcb_write_base::write_line_adapter(address_space&, unsigned int, unsigned long long, unsigned long long)+0x0069)
  0000000000228280: 0000000002ab7554 (mos6551_device::output_txd(int)+0x0084)
  0000000000228310: 0000000002abb5f1 (mos6551_device::device_start()+0x04a1)
  0000000000228420: 0000000003161800 (device_t::start()+0x00c0)
  0000000000228490: 00000000031e3817 (running_machine::start_all_devices()+0x0087)
  0000000000228590: 00000000031e922f (running_machine::start()+0x085f)
  0000000000228690: 00000000031eaa31 (running_machine::run(bool)+0x01b1)
  000000000022f440: 0000000001bd865a (mame_machine_manager::execute()+0x00ea)
  000000000022f540: 0000000001c363b5 (cli_frontend::start_execution(mame_machine_manager*, std::vector<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::allocator<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > > >&)+0x01d5)
  000000000022f6b0: 0000000001c365a5 (cli_frontend::execute(std::vector<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::allocator<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > > >&)+0x0045)
  000000000022f710: 0000000001bd68ca (emulator_info::start_frontend(emu_options&, osd_interface&, std::vector<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::allocator<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > > >&)+0x002a)
  000000000022fdb0: 0000000001b2ca32 (utf8_main(std::vector<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::allocator<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > > >&)+0x0122)
  000000000022fe50: 0000000003761b99 (wmain+0x0169)
  000000000022ff20: 0000000000401410 (__tmainCRTStartup+0x0260)
  000000000022ff50: 000000000040153b (mainCRTStartup+0x001b)
  000000000022ff80: 0000000076cf59cd (BaseThreadInitThunk+0x000d)
  000000000022ffd0: 0000000076f2a561 (RtlUserThreadStart+0x0021)