mirror of
https://github.com/Pecusx/libretro-atari800.git
synced 2026-05-21 06:39:36 +02:00
R-type
100 lines
4.3 KiB
C
100 lines
4.3 KiB
C
/*
|
|
* img_tape.h - support for CAS and raw tape images
|
|
*
|
|
* Copyright (C) 2011 Tomasz Krasuski
|
|
* Copyright (C) 2011 Atari800 development team (see DOC/CREDITS)
|
|
*
|
|
* This file is part of the Atari800 emulator project which emulates
|
|
* the Atari 400, 800, 800XL, 130XE, and 5200 8-bit computers.
|
|
*
|
|
* Atari800 is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation; either version 2 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* Atari800 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 General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with Atari800; if not, write to the Free Software
|
|
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
|
|
*/
|
|
#ifndef IMG_TAPE_H_
|
|
#define IMG_TAPE_H_
|
|
|
|
#include "atari.h"
|
|
|
|
typedef struct IMG_TAPE_t IMG_TAPE_t;
|
|
|
|
/* Checks if a file is a valid tape image, based on its first four bytes
|
|
stored in HEADER. */
|
|
int IMG_TAPE_FileSupported(UBYTE const start_bytes[4]);
|
|
|
|
/* Opens a cassette image pointed to by FILENAME.
|
|
Stores a boolean in *WRITABLE, indicating if the file is writable.
|
|
For CAS files, stores in *DESCRIPTION a pointer to the file's description.
|
|
Returns pointer to the opened file on success or NULL otherwise. */
|
|
IMG_TAPE_t *IMG_TAPE_Open(char const *filename, int *writable, char const **description);
|
|
|
|
/* Closes a tape image FILE. */
|
|
void IMG_TAPE_Close(IMG_TAPE_t *file);
|
|
|
|
/* Creates a new writable CAS file at FILENAME, with a given description.
|
|
Returns pointer to the opened file on success or NULL otherwise. */
|
|
IMG_TAPE_t *IMG_TAPE_Create(char const *filename, char const *description);
|
|
|
|
/* Reads the next tape event from FILE.
|
|
Stores duration of the event (in CPU ticks) in *DURATION.
|
|
Stores a boolean in *IS_GAP, indicating if the event is an IRG (TRUE)
|
|
or a byte (FALSE).
|
|
If *IS_GAP == FALSE, stores the byte being read in *BYTE.
|
|
Returns TRUE on success or FALSE on read error or EOF. */
|
|
int IMG_TAPE_Read(IMG_TAPE_t *file, unsigned int *duration, int *is_gap, UBYTE *byte);
|
|
|
|
/* Advances the tape file by a given DURATION (in CPU ticks) during
|
|
writing. */
|
|
void IMG_TAPE_WriteAdvance(IMG_TAPE_t *file, unsigned int duration);
|
|
|
|
/* Writes a BYTE to the tape file. POKEY_COUNTER is value of the POKEY counter
|
|
used for serial transmission.
|
|
Returns TRUE on success or FALSE on write error. */
|
|
int IMG_TAPE_WriteByte(IMG_TAPE_t *file, UBYTE byte, unsigned int pokey_counter);
|
|
|
|
/* Flushes the file's buffers. Any CAS chunk being currently written is
|
|
immediately ended.
|
|
Returns TRUE on success or FALSE on write error. */
|
|
int IMG_TAPE_Flush(IMG_TAPE_t *file);
|
|
|
|
/* Returns the file's current position (block), counted from 0. */
|
|
unsigned int IMG_TAPE_GetPosition(IMG_TAPE_t *file);
|
|
/* Returns the file's size (blocks). */
|
|
unsigned int IMG_TAPE_GetSize(IMG_TAPE_t *file);
|
|
/* Positions the file at the start of a block given in POSITION (counted from
|
|
0). */
|
|
void IMG_TAPE_Seek(IMG_TAPE_t *file, unsigned int position);
|
|
|
|
/* Returns direct state of POKEY's serial input port during tape reading.
|
|
EVENT_TIME_LEFT is number of CPU ticks left till the end of the byte that's
|
|
currently being read. */
|
|
int IMG_TAPE_SerinStatus(IMG_TAPE_t *file, int event_time_left);
|
|
|
|
/* --- Functions used by patched SIO --- */
|
|
|
|
/* Forwards the tape past a given amount of milliseconds.
|
|
Returns TRUE on success or FALSE on read error or EOF. */
|
|
int IMG_TAPE_SkipToData(IMG_TAPE_t *file, int ms);
|
|
/* Reads a record of specified LENGTH from tape and stores it in system's
|
|
memory starting ad DEST_ADDR.
|
|
Returns TRUE on success (requested number of bytes read successfully and
|
|
checksum is correct), FALSE on too short record or bad checksum,
|
|
or -1 on read error/EOF (also implicates too short record). */
|
|
int IMG_TAPE_ReadToMemory(IMG_TAPE_t *file, UWORD dest_addr, int length);
|
|
/* Writes data from system memory starting at SRC_ADDR of specified LENGTH
|
|
to a tape record. GAP is length of the pre-record gap, in ms.
|
|
Returns TRUE on success or FALSE on write error. */
|
|
int IMG_TAPE_WriteFromMemory(IMG_TAPE_t *file, UWORD src_addr, int length, int gap);
|
|
|
|
#endif /* IMG_TAPE_H_ */
|