zx-state header

The zx-state header appears right at the start of a zx-state (.szx) file.

It is used to identify the version of the file and to specify which model of ZX Spectrum (or clone) the file refers to.

Following the zx-state header is an optional ZXSTCREATOR creator information block.

Following that are the ZXSTZ80REGS and ZXSTSPECREGS blocks followed by zero or more additional blocks representing the current state of the emulated Spectrum.

// Machine identifiers
#define ZXSTMID_16K          0
#define ZXSTMID_48K          1
#define ZXSTMID_128K         2
#define ZXSTMID_PLUS2        3
#define ZXSTMID_PLUS2A       4
#define ZXSTMID_PLUS3        5
#define ZXSTMID_PLUS3E       6
#define ZXSTMID_PENTAGON128  7
#define ZXSTMID_TC2048       8
#define ZXSTMID_TC2068       9
#define ZXSTMID_SCORPION     10
#define ZXSTMID_SE           11
#define ZXSTMID_TS2068       12
#define ZXSTMID_PENTAGON512  13
#define ZXSTMID_PENTAGON1024 14
#define ZXSTMID_NTSC48K      15
#define ZXSTMID_128KE        16

// Flags (chFlags)
#define ZXSTMF_ALTERNATETIMINGS 1

typedef struct _tagZXSTHEADER
{
  DWORD dwMagic;
  BYTE  chMajorVersion;
  BYTE  chMinorVersion;
  BYTE  chMachineId;
  BYTE  chFlags;
} ZXSTHEADER, *LPZXSTHEADER;

Members

dwMagic

Byte sequence of 'Z', 'X', 'S', 'T' to identify the file as a zx-state file.

chMajorVersion

Major version number of the file format. Currently 1.

chMinorVersion

Minor version number of the file format. Currently 4.

chMachineId

The model of ZX Spectrum (or clone) to switch to when loading the file. This is one of:

Value	Meaning
ZXSTMID_16K	16k ZX Spectrum
ZXSTMID_48K	48k ZX Spectrum or ZX Spectrum+
ZXSTMID_128K	ZX Spectrum 128
ZXSTMID_PLUS2	ZX Spectrum +2
ZXSTMID_PLUS2A	ZX Spectrum +2A/+2B
ZXSTMID_PLUS3	ZX Spectrum +3
ZXSTMID_PLUS3E	ZX Spectrum +3e
ZXSTMID_PENTAGON128	Pentagon 128
ZXSTMID_TC2048	Timex Sinclair TC2048
ZXSTMID_TC2068	Timex Sinclair TC2068
ZXSTMID_SCORPION	Scorpion ZS-256
ZXSTMID_SE	ZX Spectrum SE
ZXSTMID_TS2068	Timex Sinclair TS2068
ZXSTMID_PENTAGON512	Pentagon 512
ZXSTMID_PENTAGON1204	Pentagon 1024
ZXSTMID_NTSC48K	48k ZX Spectrum (NTSC)
ZXSTMID_128Ke	ZX Spectrum 128Ke

chFlags

Various flags. This can currently only be:

Flag	Meaning
ZXSTMF_ALTERNATETIMINGS	If set, the emulated Spectrum uses alternate timings (one cycle later than normal timings). If reset, the emulated Spectrum uses standard timings. This flag is only applicable for the ZXSTMID_16K, ZXSTMID_48K and ZXSTMID_128K models.

Revision history

Available since version 1.0

ZXSTMID_NTSC48K and ZXSTMID_128Ke were added in version 1.4

ZXSTMF_ALTERNATETIMINGS was added in version 1.4